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1Back to top Go down   Fuel in oil Empty Fuel in oil Sat Jan 14, 2017 4:31 pm

Jonas Bodin

Jonas Bodin
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Hi there!

I bought my K100rt last year and rode it during the summer.

What I did notice was that the oil level increased... It's not water going into the oil as the oil remains clear. I have changed the oil a couple of times and every time the oil smells a lot of fuel -not surprising as we're talking deciliters going into the oil:shock:

I have the european tank-ventilation so that's not the way the fuel goes into the oil.

Took out the injectors and cranked the engine to see if they would leak afterwards but they didn't.

I haven't found anyone else with this problem so I would appreciate any help on what to look for.

    

2Back to top Go down   Fuel in oil Empty Re: Fuel in oil Sat Jan 14, 2017 9:19 pm

Holister

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There's a good chance your temp sensor has gone open circuit which tells the FICU that it extremely cold and so it pumps in huge amounts of fuel at startup. That fuel then finds its way into the cylinders and past the rings into the sump. Your oil will be cactus with even a small amount of fuel in it.

To test: remove the FICU plug and use a DMM to measure the resistance between pins #10 and #13 counting from the lead end. You should be seeing 2.5KΩ @20 ̊C and 300Ω @ 80 ̊C

It could simply be corrosion on the threaded body of the sensor which provides the earthing. Otherwise you'll need to buy a new one.


__________________________________________________

1989 K100RT     VIN  0097367 (naked)  
1996 K1100RS   VIN  0451808
 Fuel in oil Austra12    Fuel:  95 Octane
Engine Oil: Nulon Full Synthetic 15W50
Gear Box Oil:  Nulon Synthetic 75W90
    

3Back to top Go down   Fuel in oil Empty Re: Fuel in oil Sun Jan 15, 2017 8:42 am

Jonas Bodin

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Holister wrote:There's a good chance your temp sensor has gone open circuit which tells the FICU that it extremely cold and so it pumps in huge amounts of fuel at startup. That fuel then finds its way into the cylinders and past the rings into the sump. Your oil will be cactus with even a small amount of fuel in it.

To test: remove the FICU plug and use a DMM to measure the resistance between pins #10 and #13 counting from the lead end. You should be seeing 2.5KΩ @20 ̊C and 300Ω @ 80 ̊C

It could simply be corrosion on the threaded body of the sensor which provides the earthing. Otherwise you'll need to buy a new one.
This sounds interesting! Will test this as soon as I can get the time.

I suppose I need to drain the cooling-system to be able to unscrew the sensor and look for rust?

Thanks for the input! Fuel in oil 112350

    

4Back to top Go down   Fuel in oil Empty Re: Fuel in oil Mon Jan 16, 2017 2:41 pm

Motorbike Mike

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I bought an old K100 some years back and got it running-eventually. It was difficult to start after a few days rest, it was kicking out black smoke in abundance when it did fire.
I traced it to a sticking injector, it was stuck open and the residual fuel pressure in the system was pouring into the engine. It might be worth taking the injectors out out to check all injectors are seating properly.

Mike.

    

5Back to top Go down   Fuel in oil Empty Re: Fuel in oil Mon Jan 16, 2017 4:12 pm

Jonas Bodin

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Motorbike Mike wrote:I bought an old K100 some years back and got it running-eventually. It was difficult to start after a few days rest, it was kicking out black smoke in abundance when it did fire.
I traced it to a sticking injector, it was stuck open and the residual fuel pressure in the system was pouring into the engine. It might be worth taking the injectors out out to check all injectors are seating properly.

Mike.
Hi Mike!

I had them out and they didn't leak on that occasion, but perhaps it's an intermittent fault? Will start with the temp-sensor. If that turns out to be okay maybe it's a good idea to investigate the injectors more thoroughly?

Thanks

    

6Back to top Go down   Fuel in oil Empty Re: Fuel in oil Mon Jan 16, 2017 5:28 pm

Dai

Dai
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If you pull the injectors make sure that you have new o-rings first. The ones that are on there will have hardened to shape and will definately leak if you reuse them.


__________________________________________________
1983 K100 naked upgraded to K100LT spec after spending time as an RS and an RT
1987 K100RT
Others...
1978 Moto Guzzi 850-T3, 1979 Moto Guzzi 850-T3 California,1993 Moto Guzzi 1100ie California
2020 Royal Enfield Bullet 500
    

7Back to top Go down   Fuel in oil Empty Re: Fuel in oil Mon Jan 16, 2017 8:16 pm

blaKey

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Wasn't something posted a while ago where someone here had the same problem (increasing oil level) and it was traced to a faulty fuel pressure regulator allowing fuel to enter the crankcase.

I could be wrong however... Sleep


__________________________________________________
Neil
K100RS 1986 RED!

Dress for the ride and the potential slide.
    

8Back to top Go down   Fuel in oil Empty Re: Fuel in oil Mon Jan 16, 2017 8:56 pm

charlie99

charlie99
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good point blakey


__________________________________________________
cheezy grin whilst riding, kinda bloke ....oh the joy !!!! ...... ( brick aviator )

'86 K100 RT..#0090401 ..."Gerty" ( Gertrude Von Clickandshift ) --------O%O
'86 k100 rs.. #######..  "Fred " (f(rame) red ) ( Fredrick leichtundschnell ) - -
bits and pieces from many kind friends across the k100 world ...with many thanks ..
1987 k100rs ########   "Red"  - (red sports rs TWB style )
1989 K100rt #009637   "Black Betty"  (naked rt ala Nigel , now sporting an rs main fairing )
    

9Back to top Go down   Fuel in oil Empty Re: Fuel in oil Tue Jan 17, 2017 5:01 pm

Jonas Bodin

Jonas Bodin
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blaKey wrote:Wasn't something posted a while ago where someone here had the same problem (increasing oil level) and it was traced to a faulty fuel pressure regulator allowing fuel to enter the crankcase.

I could be wrong however... Sleep
I pulled of the vacuum hose which leads to the fuel pressure regulator and sucked to se if there would be fuel -but it wasn't! But maybe there's another way to tell if it's faulty? Will try to find that post  Fuel in oil 112350

    

10Back to top Go down   Fuel in oil Empty Re: Fuel in oil Fri Jan 20, 2017 7:05 pm

Jonas Bodin

Jonas Bodin
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Holister wrote:There's a good chance your temp sensor has gone open circuit which tells the FICU that it extremely cold and so it pumps in huge amounts of fuel at startup. That fuel then finds its way into the cylinders and past the rings into the sump. Your oil will be cactus with even a small amount of fuel in it.

To test: remove the FICU plug and use a DMM to measure the resistance between pins #10 and #13 counting from the lead end. You should be seeing 2.5KΩ @20 ̊C and 300Ω @ 80 ̊C

It could simply be corrosion on the threaded body of the sensor which provides the earthing. Otherwise you'll need to buy a new one.
Measured the temp sensor today and it was 2.8kΩ at around 20 degrees C. As the bike is a bit in pieces right now I can't get it up to 80 degrees C unless I get the sensor out and put it in hot water...


The sensor doesn't seem to be completely off by the 20 degrees measurement. Will measure it at a higher temperature as soon as I get the chance but get the feeling this maybe wasn't the "easy fix" I was looking for..


Are there any other ideas on what might be causing this weird problem?

    

11Back to top Go down   Fuel in oil Empty Re: Fuel in oil Fri Jan 20, 2017 7:50 pm

Laitch

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Jonas Bodin wrote:I bought my K100rt last year and rode it during the summer.
What I did notice was that the oil level increased... 
There wasn't an increase of black deposit at the exhaust pipe, hard starting, or a loss of power?  The only symptom was an increase in crankcase fluid volume?


__________________________________________________
1995 K75 90,000 miles
    

12Back to top Go down   Fuel in oil Empty Re: Fuel in oil Sat Jan 21, 2017 7:32 am

Jonas Bodin

Jonas Bodin
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Laitch wrote:
Jonas Bodin wrote:I bought my K100rt last year and rode it during the summer.
What I did notice was that the oil level increased... 
There wasn't an increase of black deposit at the exhaust pipe, hard starting, or a loss of power?  The only symptom was an increase in crankcase fluid volume?
Since I believe the bike had this problem already when I bought it I have a hard time telling if it has been starting to run worse, but I can´t say it runs bad... Almost allways starts on first attempt, BUT sometimes (not often) the starter doesn´t crank the Engine. It's like if it would be low on battery, but then I just try again and it starts! Don't know if this can have something to do with the other problem?

There is a bit of black deposit around the exhaust, but can´t tell if it has increased or not!

I rode the bike for about 100km during a week (short trips) and the oil level increased with 0.6litres... Shocked

Will be doing a compression test on the bike to see in what shape the piston rings are! But I'm hoping it won't have anything to do with them... tearing down the whole Engine is not on the wishlist santa

    

13Back to top Go down   Fuel in oil Empty Re: Fuel in oil Sat Jan 21, 2017 7:51 am

92KK 84WW Olaf

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If your oil level is increasing that much the extra liquid is getting in somewhere and it wont be to do with piston rings for sure. When the engine is cold piston ring end gaps open up exactly as its designed to do and if there is petrol in the bores it will run into the crank case. But for this to happen the K would have to parked on centre stand or be leaning over to the right or else have an enormous amount of liquid inside the chamber above the pistons.

600ml of an increase in 100kms is massive, makes me wonder are you sure the whole of that 600ml additional liquid is petrol and not coolant? But no drop in coolant? Oil level checked with engine cold and set with bike on main stand?  If its petrol I can only suspect some very serious problem with an injector that's allowing fuel pass through when the engine is off. Rich running might produce staining on the muffler and funny running but the when running rich the fuel tends to either burn off or go out the exhaust unburnt.


__________________________________________________
1992 K100LT 0193214 Bertha Blue 101,000 miles
1984 K100RT 0022575 Brutus Baja Red 578 bought 36,000 now 89,150 miles
1997 K1100LT 0188024 Wotan Mystic Red 689 58,645 now 106,950 miles Deceased.
1983 K100RS 0011157 Fricka 606 Alaska Blue 29,495 miles Damn K Pox Its a Bat outta Hell Now 58,200 miles. 
1996 K1100LT 0233004 Lohengrin Mystic Red 38,000 miles currently 48,061 miles.
1983 K100RS 0004449 Odette R100 colours 58,000 miles. Sprint fairing now 61,190 miles

Past:
1968 Yamaha 80 YG1
1971 Yamaha 125 YAS-1
1968 Honda 125 SS
1970 Honda CD 175
1973 Honda CB500-4
Honda CX 500
    

14Back to top Go down   Fuel in oil Empty Re: Fuel in oil Sat Jan 21, 2017 8:26 am

Jonas Bodin

Jonas Bodin
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92KK 84WW Olaf wrote:If your oil level is increasing that much the extra liquid is getting in somewhere and it wont be to do with piston rings for sure. When the engine is cold piston ring end gaps open up exactly as its designed to do and if there is petrol in the bores it will run into the crank case. But for this to happen the K would have to parked on centre stand or be leaning over to the right or else have an enormous amount of liquid inside the chamber above the pistons.

600ml of an increase in 100kms is massive, makes me wonder are you sure the whole of that 600ml additional liquid is petrol and not coolant? But no drop in coolant? Oil level checked with engine cold and set with bike on main stand?  If its petrol I can only suspect some very serious problem with an injector that's allowing fuel pass through when the engine is off. Rich running might produce staining on the muffler and funny running but the when running rich the fuel tends to either burn off or go out the exhaust unburnt.

Yep it's massive! I'm checking the oil level on the center stand. No drop in coolant and the oil is clear -which wouldn't be the case if coolant had gotten into it.

I'm suspecting a faulty injector as well, but when I had them out they weren't leaking anything at all... And with the amount of fuel going into the oil it should be leaking a lot... But maybe it can be an intermittent problem?

I haven't got a clue on what to do -that's why I'm hoping to get some advice on what to look for in this forum  Very Happy

    

15Back to top Go down   Fuel in oil Empty Re: Fuel in oil Sat Jan 21, 2017 8:29 am

92KK 84WW Olaf

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All I can think is that there is no other way than through the injectors for fuel to get into the engine oil in such quantities.

The engine crank case vents into the air intake box . The vacuum pipe on no 4 cylinder connects if I am right to the Fuel Pressure Regulator and affects the fuel flow. I am just wondering could there be a misconnection there any where.  But I struggle to see how large amounts of petrol would get from the air intake box into the crank case. The smell of fuel would be horrific.


The fuel tank ventilates to atmosphere except I think in the California spec fuel emission controls. I have a feeling these ones are a closed system vented into the crank case or air intake for the vapours to be burnt off.


__________________________________________________
1992 K100LT 0193214 Bertha Blue 101,000 miles
1984 K100RT 0022575 Brutus Baja Red 578 bought 36,000 now 89,150 miles
1997 K1100LT 0188024 Wotan Mystic Red 689 58,645 now 106,950 miles Deceased.
1983 K100RS 0011157 Fricka 606 Alaska Blue 29,495 miles Damn K Pox Its a Bat outta Hell Now 58,200 miles. 
1996 K1100LT 0233004 Lohengrin Mystic Red 38,000 miles currently 48,061 miles.
1983 K100RS 0004449 Odette R100 colours 58,000 miles. Sprint fairing now 61,190 miles

Past:
1968 Yamaha 80 YG1
1971 Yamaha 125 YAS-1
1968 Honda 125 SS
1970 Honda CD 175
1973 Honda CB500-4
Honda CX 500
    

16Back to top Go down   Fuel in oil Empty Re: Fuel in oil Sat Jan 21, 2017 10:32 am

Motorbike Mike

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92KK 84WW Olaf wrote:All I can think is that there is no other way than through the injectors for fuel to get into the engine oil in such quantities.
I did mention that a while back. 
I'd also think that continued use of the bike with diluted oil will probably destroy the engine.

    

17Back to top Go down   Fuel in oil Empty Re: Fuel in oil Sat Jan 21, 2017 11:19 am

Jonas Bodin

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Motorbike Mike wrote:
92KK 84WW Olaf wrote:All I can think is that there is no other way than through the injectors for fuel to get into the engine oil in such quantities.
I did mention that a while back. 
I'd also think that continued use of the bike with diluted oil will probably destroy the engine.
Hi Mike!

As I mentioned I had the injectors taken out but couldn't see that anyone of them was leaking after cranking the engine. Would expect a lot of fuel leaking if this was the case -but nothing... There is ofcourse a chance that it happens when the engine gets hot after driving it for a while. When I took the injectors out they were cold! And as I mentioned earlier it may be an intermittant problem as well!

What I'm hoping for is to get som advise on how to check where the problem is! Can i test the injectors in some other way without having to send them away? Or might it be something in the FI-unit which is possible to check in some way?

I understand that it will be bad for the engine to run with a lot of fuel in the oil and therefore I have just been riding short distances this summer while trying to troubleshoot the problem... Have also changed the oil a number of times, so I hope I have stayed away from problems with the engine! The Grand plan is to be able to ride the bike without changing oil as often as I fill it with gas though Rolling Eyes

    

18Back to top Go down   Fuel in oil Empty Re: Fuel in oil Sat Jan 21, 2017 11:31 am

Motorbike Mike

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The only way for fuel to enter the engine is by the fuel system. If it's over fueling that much while it's running, the fuel would wash the bores clean but at the same time the motor would surely run over rich to the point of not running at all IMO. 
As I said before I had similar problem with injectors staying open dumping fuel into the engine over night or over a couple of days. 
That's where I'd be concentrating my search for the problem. 

Good luck anyway.

    

19Back to top Go down   Fuel in oil Empty Re: Fuel in oil Sat Jan 21, 2017 12:27 pm

Born Again Eccentric

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Motorbike Mike wrote:As I said before I had similar problem with injectors staying open dumping fuel into the engine over night or over a couple of days. 
That's where I'd be concentrating my search for the problem. 
My immediate thought was that one or more injectors were stuck. My experience of finding fuel dilution of sump oil (in marine diesel engines) is that it has always been a symptom of a dodgy injector.

I think you are spot on Mike - a faulty injector would allow the fuel to dribble into the cylinder while the engine is stopped, until the fuel rail has depressurised. Petrol, being considerably less viscous than engine oil, will then have little difficulty working its way past the stationary piston rings and into the sump. 

For the sump level to visibly increase is a big concern - that implies a lot of petrol getting into the sump and that will badly affect the viscosity and lubricity of the engine oil. If the lub oil can't maintain a fine film on all moving parts, you will get increased engine wear. In a hot engine, this problem will be worse as the petrol may evaporate quickly and give dry spots and the petrol vapours will accumulate in the sump which increases the risk of a crank case explosion (would also need a blocked crankcase breather tube to allow the sump to pressurise enough to allow compression ignition). 

Jonas, your regular oil changes are very wise - but are not actually dealing with the problem. When you tested/replaced the injectors, did you fit new O seals? Have you tested the fuel pressure regulator (or checked the fuel rail pressure). There are several posts on these issues.


__________________________________________________
Fuel in oil Uk-log10 Fuel in oil Sco-lo15
                              Paul  Fuel in oil 905546712

"Heidi" K100LT 1991 (Grey) (VIN 0190172 Engine No. 104EB 2590 2213) - 5th owner. January 2014 (34,000 - 61,000 miles and counting....)
"Gretel" K100LT 1989 (Silver Grey) (VIN 0177324 Engine No. 104EA 2789 2211) - 4th+ owner. September 2015 (58,500miles and counting....). Cat C Insurance write-off rebuild Feb 17
"Donor" K100LT 1990 (Red)  (VIN 0178091 Engine No. 4489 2024) - 6th & final owner (crash write-off now donor bike).   June 2012 (73,000 miles) to November 2013 (89,500 miles)
    

20Back to top Go down   Fuel in oil Empty Re: Fuel in oil Sat Jan 21, 2017 8:06 pm

Jonas Bodin

Jonas Bodin
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Born Again Eccentric wrote:
Motorbike Mike wrote:As I said before I had similar problem with injectors staying open dumping fuel into the engine over night or over a couple of days. 
That's where I'd be concentrating my search for the problem. 
My immediate thought was that one or more injectors were stuck. My experience of finding fuel dilution of sump oil (in marine diesel engines) is that it has always been a symptom of a dodgy injector.

I think you are spot on Mike - a faulty injector would allow the fuel to dribble into the cylinder while the engine is stopped, until the fuel rail has depressurised. Petrol, being considerably less viscous than engine oil, will then have little difficulty working its way past the stationary piston rings and into the sump. 

For the sump level to visibly increase is a big concern - that implies a lot of petrol getting into the sump and that will badly affect the viscosity and lubricity of the engine oil. If the lub oil can't maintain a fine film on all moving parts, you will get increased engine wear. In a hot engine, this problem will be worse as the petrol may evaporate quickly and give dry spots and the petrol vapours will accumulate in the sump which increases the risk of a crank case explosion (would also need a blocked crankcase breather tube to allow the sump to pressurise enough to allow compression ignition). 

Jonas, your regular oil changes are very wise - but are not actually dealing with the problem. When you tested/replaced the injectors, did you fit new O seals? Have you tested the fuel pressure regulator (or checked the fuel rail pressure). There are several posts on these issues.
Hi!

As my bike has the European tank ventilation there can't be any other way for the fuel to get into the oil than from the injectors. The question is when and how it occurs! Is it while driving or in between? Is the problem the injectors or the FI-unit?

I can't say the bike is running bad and the exhausts aren't black. This points toward leaking in between when the bike is used...

When I "tested" the injectors I simply pulled them out and cranked the engine and then looked for leaking. Did this a couple of times and not a drip was spilled! Were kind of hoping to se one or more injector to be leaking 'cause this would have solved the problem. I didn't replace the O-rings as I were thinking that I might be pulling the injectors out sometime soon again, and the old ones actually looked quite ok. I have new O-rings so I will be changing them on occasion.

Will look for fuel regulator posts to see if I can learn anything helpful from that.

The oil changes have been from a "spare the engine" point of view and is nothing I want to be doing in the future. Have been riding very sparingly last summer because of this problem!

Thanks for your support Mike!

    

21Back to top Go down   Fuel in oil Empty Re: Fuel in oil Sun Jan 22, 2017 2:46 am

Motorbike Mike

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How about taking the injectors out and leaving them out, perhaps sitting in a small tray to catch any fuel that might be weeping out? Leave it like that at least overnight or for a few days. 
When mine were leaking the bike ran as normal because it was delivering fuel at the normal rate but just couldn't hold back full static pressure.

    

22Back to top Go down   Fuel in oil Empty Re: Fuel in oil Sun Jan 22, 2017 4:03 am

Point-Seven-five

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I seem to have missed the post where you state the year of your bike.  I'm not sure if it really makes a difference, but it would be nice to know.  THere are changes made from year to year that may affect how you troubleshoot a problem.

Maybe you could list that information in your profile signature line.


__________________________________________________
Present: 1991 K100RS "Moby Brick Too"
 
Past:
1994 K75RT "Ilsa, She Wolf of the SS"
1988 K100RS SE "Special Ed"
1994 K75S "Cheetos"
1992 K100RS "Moby Brick" R.I.P.
1982 Honda FT500
1979 Honda XR185
1977 Honda XL125
1974 Honda XL125
1972 OSSA Pioneer 250
1968 Kawasaki 175
    

23Back to top Go down   Fuel in oil Empty Re: Fuel in oil Sun Jan 22, 2017 6:11 am

Jonas Bodin

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Point-Seven-five wrote:I seem to have missed the post where you state the year of your bike.  I'm not sure if it really makes a difference, but it would be nice to know.  THere are changes made from year to year that may affect how you troubleshoot a problem.

Maybe you could list that information in your profile signature line.
I thought I had done that...  Smile

It's a RT from -89.

    

24Back to top Go down   Fuel in oil Empty Re: Fuel in oil Sun Jan 22, 2017 6:18 am

Jonas Bodin

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Motorbike Mike wrote:How about taking the injectors out and leaving them out, perhaps sitting in a small tray to catch any fuel that might be weeping out? Leave it like that at least overnight or for a few days. 
When mine were leaking the bike ran as normal because it was delivering fuel at the normal rate but just couldn't hold back full static pressure.
I'm quite certain that I left them out overnight (bad memory  bounce ) but I will take the injectors out again and run some longer tests  Fuel in oil 112350

    

25Back to top Go down   Fuel in oil Empty Re: Fuel in oil Sun Jan 22, 2017 10:27 am

Point-Seven-five

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Just curious, how much cranking does it take to start the engine?  I ask because if a significant amount of fuel leaks through through the injectors when the engine is off I would expect the fuel pump to need to run for a couple seconds before the pressure in the rail is high enough to inject fuel.

I am not sure if the European bikes have it, but you might want to look.  On the top of the engine block in the middle of the front, just above the timing chain cover is a small 4mm brass tube. 

At one time there was some sort of check valve and tubing connected to it.  On my bikes it has been capped.  By any chance is there some tubing attached to it on your bike?  If so, where does it go?  This could allow foreign stuff, possibly fuel, into the crankcase.


__________________________________________________
Present: 1991 K100RS "Moby Brick Too"
 
Past:
1994 K75RT "Ilsa, She Wolf of the SS"
1988 K100RS SE "Special Ed"
1994 K75S "Cheetos"
1992 K100RS "Moby Brick" R.I.P.
1982 Honda FT500
1979 Honda XR185
1977 Honda XL125
1974 Honda XL125
1972 OSSA Pioneer 250
1968 Kawasaki 175
    

26Back to top Go down   Fuel in oil Empty Re: Fuel in oil Sun Jan 22, 2017 1:21 pm

Jonas Bodin

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Point-Seven-five wrote:Just curious, how much cranking does it take to start the engine?  I ask because if a significant amount of fuel leaks through through the injectors when the engine is off I would expect the fuel pump to need to run for a couple seconds before the pressure in the rail is high enough to inject fuel.

I am not sure if the European bikes have it, but you might want to look.  On the top of the engine block in the middle of the front, just above the timing chain cover is a small 4mm brass tube. 

At one time there was some sort of check valve and tubing connected to it.  On my bikes it has been capped.  By any chance is there some tubing attached to it on your bike?  If so, where does it go?  This could allow foreign stuff, possibly fuel, into the crankcase.
It starts quite instantly. Except on some rare occasions when it's like the starter doesn't have the power or possibly one or more cylinders could be filled with fuel? At least that was my theory for a while... 

Don't think I have that check valve on my bike! I will have a look tomorrow.

    

27Back to top Go down   Fuel in oil Empty Re: Fuel in oil Sun Jan 22, 2017 3:07 pm

Motorbike Mike

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The cylinders could be starting to hydraulic lock, don't bend a rod trying to crank the motor. 😥

    

Jonas Bodin

Jonas Bodin
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Just a question about the engine breather hose.

Mine is pretty cracked! I have bought a new one and will be changing it soon. Just want to rule out that this can have something to do with the fuel in the oil...

    

29Back to top Go down   Fuel in oil Empty Re: Fuel in oil Sun Jan 22, 2017 4:58 pm

Laitch

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Motorbike Mike wrote:The cylinders could be starting to hydraulic lock, don't bend a rod trying to crank the motor. 😥
+1
There is an example on MOTOBRICK.COM of that happening from the output of a leaking fuel pressure regulator. Put a gauge on it.


__________________________________________________
1995 K75 90,000 miles
    

30Back to top Go down   Fuel in oil Empty Re: Fuel in oil Mon Jan 23, 2017 1:22 am

Holister

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My thoughts are that if the bike is running ok as Jonas says, then the fpr is ok. 
I doubt excess fuel would pass the rings while the motor is running ok so I'm thinking this is an issue at startup or while the bike is sitting not running.
Excess fuel at startup would be down to FICU or temp sensor.
While the bike is sitting, would be due to faulty or dirty injectors.
Try cleaning the FICU connection with DeoxiT.
Have your injectors cleaned and tested.


__________________________________________________

1989 K100RT     VIN  0097367 (naked)  
1996 K1100RS   VIN  0451808
 Fuel in oil Austra12    Fuel:  95 Octane
Engine Oil: Nulon Full Synthetic 15W50
Gear Box Oil:  Nulon Synthetic 75W90
    

31Back to top Go down   Fuel in oil Empty Re: Fuel in oil Tue Jan 24, 2017 7:48 am

Jonas Bodin

Jonas Bodin
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Holister wrote:My thoughts are that if the bike is running ok as Jonas says, then the fpr is ok. 
I doubt excess fuel would pass the rings while the motor is running ok so I'm thinking this is an issue at startup or while the bike is sitting not running.
Excess fuel at startup would be down to FICU or temp sensor.
While the bike is sitting, would be due to faulty or dirty injectors.
Try cleaning the FICU connection with DeoxiT.
Have your injectors cleaned and tested.

Hi there!

I'm on your line! The bike runs well and no black exhausts i.e the fuel must get into the oil inbetween the rides...

The temp sensor seem to be ok. Have measured it only at 20 degrees celcius, but if it was shorted out (our what the expression is   Question   ) I guess the value would be wrong.

Leaves the FICU or injectors!

I will clean the FICU connection and take out the injectors once again to se if they are leaking. Thinking of doing a compression test just to rule bad piston rings out as well

At the moment I'm working on the electrics so the bike can't be started right now. Will return with information on how things worked out -or not- as soon as I have performed these tests.

    

32Back to top Go down   Fuel in oil Empty Re: Fuel in oil Tue Jan 24, 2017 8:38 am

92KK 84WW Olaf

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Bad piston rings won't be the cause. If fuel is getting into the cylinder it will get past good piston rings.

Definitely look at the injectors. Seals are cheap enough to be able to take them out.

Compression test is no harm but I don't think it will provide.


__________________________________________________
1992 K100LT 0193214 Bertha Blue 101,000 miles
1984 K100RT 0022575 Brutus Baja Red 578 bought 36,000 now 89,150 miles
1997 K1100LT 0188024 Wotan Mystic Red 689 58,645 now 106,950 miles Deceased.
1983 K100RS 0011157 Fricka 606 Alaska Blue 29,495 miles Damn K Pox Its a Bat outta Hell Now 58,200 miles. 
1996 K1100LT 0233004 Lohengrin Mystic Red 38,000 miles currently 48,061 miles.
1983 K100RS 0004449 Odette R100 colours 58,000 miles. Sprint fairing now 61,190 miles

Past:
1968 Yamaha 80 YG1
1971 Yamaha 125 YAS-1
1968 Honda 125 SS
1970 Honda CD 175
1973 Honda CB500-4
Honda CX 500
    

33Back to top Go down   Fuel in oil Empty Re: Fuel in oil Tue Jan 24, 2017 8:12 pm

Rick G

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There are 2 ways to get fuel into the crankcase. A leaking injector or a leaking fuel pressure regulator. Any other way except via the filler cap would have to be a very strange happening and I would say that it would be found very quickly.
If the diaphragm in the FPR is leaking the fuel will be going via the vacuum take off on #4 TB so remove that tube and block the outlet to eliminate that.


__________________________________________________
"Man sacrifices his health in order to make money.
Then he sacrifices money to recuperate his health.
And then he is so anxious about the future that he does not enjoy the present; the result being that he does not live in the present or the future; he lives as if he is never going to die, and then dies having never really lived."   Dalai Lama


Bikes 1999 K1100 LT with a Big Block 1200
    

34Back to top Go down   Fuel in oil Empty Re: Fuel in oil Tue Jan 24, 2017 8:53 pm

TacKler

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Laitch wrote:
Motorbike Mike wrote:The cylinders could be starting to hydraulic lock, don't bend a rod trying to crank the motor. 😥
+1
There is an example on MOTOBRICK.COM of that happening from the output of a leaking fuel pressure regulator. Put a gauge on it.

Would you be able to post a link to this?  

I have only ever seen a cylinder hydraulic lock caused by engine oil.  Admittedly this is on the lower cylinders of radial aircraft engines.


__________________________________________________
Red 1991 K75S
    

35Back to top Go down   Fuel in oil Empty Re: Fuel in oil Tue Jan 24, 2017 9:08 pm

Laitch

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TacKler wrote:Would you be able to post a link to this?  
Here's the post with a summary. There are photos earlier in the thread.


__________________________________________________
1995 K75 90,000 miles
    

36Back to top Go down   Fuel in oil Empty Re: Fuel in oil Tue Jan 24, 2017 9:42 pm

Rick G

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TacKler wrote:
Laitch wrote:
Motorbike Mike wrote:The cylinders could be starting to hydraulic lock, don't bend a rod trying to crank the motor. 😥
+1
There is an example on MOTOBRICK.COM of that happening from the output of a leaking fuel pressure regulator. Put a gauge on it.

Would you be able to post a link to this?  

I have only ever seen a cylinder hydraulic lock caused by engine oil.  Admittedly this is on the lower cylinders of radial aircraft engines.
The Kawasaki Z1300 six are renowned for it because the float bowl has no overflow and the fuel runs down into #1 cylinder.


__________________________________________________
"Man sacrifices his health in order to make money.
Then he sacrifices money to recuperate his health.
And then he is so anxious about the future that he does not enjoy the present; the result being that he does not live in the present or the future; he lives as if he is never going to die, and then dies having never really lived."   Dalai Lama


Bikes 1999 K1100 LT with a Big Block 1200
    

37Back to top Go down   Fuel in oil Empty Re: Fuel in oil Tue Jan 24, 2017 10:03 pm

TacKler

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Thanks Laitch.  Quite informative and relevant to me as a 75 rider.


__________________________________________________
Red 1991 K75S
    

38Back to top Go down   Fuel in oil Empty Re: Fuel in oil Fri Jan 27, 2017 6:24 am

Jonas Bodin

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RicK G wrote:There are 2 ways to get fuel into the crankcase. A leaking injector or a leaking fuel pressure regulator. Any other way except via the filler cap would have to be a very strange happening and I would say that it would be found very quickly.
If the diaphragm in the FPR is leaking the fuel will be going via the vacuum take off on #4 TB so remove that tube and block the outlet to eliminate that.
Hi Rick!

Is it possible to take off the vacuum hose from the FPR where it enters the TB and start the bike to see if there is leaking fuel from the diaphragm?

    

39Back to top Go down   Fuel in oil Empty Re: Fuel in oil Fri Jan 27, 2017 8:12 am

Rick G

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Yeah just block off the little brass tube on the throttle body so it runs OK.


__________________________________________________
"Man sacrifices his health in order to make money.
Then he sacrifices money to recuperate his health.
And then he is so anxious about the future that he does not enjoy the present; the result being that he does not live in the present or the future; he lives as if he is never going to die, and then dies having never really lived."   Dalai Lama


Bikes 1999 K1100 LT with a Big Block 1200
    

40Back to top Go down   Fuel in oil Empty Re: Fuel in oil Sun Jan 29, 2017 3:30 pm

Jonas Bodin

Jonas Bodin
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RicK G wrote:Yeah just block off the little brass tube on the throttle body so it runs OK.
Thanks  Fuel in oil 112350

    

41Back to top Go down   Fuel in oil Empty Re: Fuel in oil Sun Feb 05, 2017 10:05 am

wilbo

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Hi, i'm only a newbiew to K100's but I have had a similar issue to this on a Kawasaki gtr1000 Concours that I had 2 years ago.  Although it was a carburettor and not injector the principles I feel are the same.

I was parking my bike up of an evening an noticing a strong smell of fuel when I walked past it, I traced it to fuel coming out of the airbox which I thought was bizzare and I also noticed my oil level had gone up and smelt of fuel.

********************************************************
***You maybe at risk of Hydrolock as mentioned so dont start your bike***
*********************************************************

Hydrolock was a killer for Kawasaki GTR1000 Concours and bent many a rod.  I eventually traced the fault to a diaphragm in the vacum line that delivered the fuel, it was blocking so when I turned the bike off it left the vacum open and the fuel was seeping through a bad carb where the needle did not shut off tight with the float, filling the bore, past it and into oil and back out the airbox.

Like has already been suggested it is probably an injector staying open and the residual pressure in the system I think it is circa 36psi forcing the fuel into your engine.  Best thing is to leave your injectors out and if you do want to try and start your engine remove your plugs.  I did this on the kawasaki then when I turned the engine over fuel poured out of the cylinder and hit my garage roof!  Atleast I did not hydrolock the engine and I knew which carb had the issue also, this could lead you down the injector as well.

    

42Back to top Go down   Fuel in oil Empty Re: Fuel in oil Sun Feb 05, 2017 11:51 am

wilcom

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Jonas Bodin wrote:
Laitch wrote:
Jonas Bodin wrote: BUT sometimes (not often) the starter doesn´t crank the Engine. It's like if it would be low on battery, but then I just try again and it starts! Don't know if this can have something to do with the other problem?

This could be a hydraulic lock up with fuel in the bore. won's turn over until the fuel is forced passed the rings. If you encounter this again I would immediately pull the plugs and spin the motor over to see if a bunch of fuel exits one of the cylinders... If so it would narrow your search to that cylinder....


__________________________________________________
Joe Wilkerson
Telephone man with a splash of Data
Menifee, CA
1989 K100RS SE


past
1979 BMW R65
1980 BMW R65
1982 BMW R80RT (Gas hog)
1974 BMW R90/6
1972 BMW R75
1964 BMW R50 Earles forks( as reliable as a hammer)
2009 Buel XB12R (the FI sucked)
1999 Buell  (Yeah! a carburetor)
2005 Suzuki Bandit 1200
1991 Kaw ZX-11 OMG
1966 Norton 750 (had to have a chase car for anything over 5 miles)
1961 Norton 650' (see above)
1964 Honda 305 Superhawk
and a dozen or so I have forgotten about..........
    

43Back to top Go down   Fuel in oil Empty Re: Fuel in oil Sun Feb 05, 2017 12:12 pm

Point-Seven-five

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Following this thread I am curious about exactly how much fuel and how quickly it gets into the oil.  Deciliters has been mentioned, but nowhere has the time interval been mentioned. 

Volume and time interval will define flow rate which helps describe whatever the orifice the fuel is leaking through.  Is the tank emptying into the crankcase overnight?  Or is the level creeping up a millimeter or two every couple of days?  Am I the only one who doesn't know this?  Am I the only one who wants to know?

In any event, why not install one of these in the fuel line from the pump to the rail.   That will eliminate the additional head to the tank as well as the large volume available through the siphon effect.

http://www.ebay.com/itm/Metal-Inline-Fuel-Valve-Petcock-5-16-Motorcycle-Fuel-Diesel-Gas-Petrol-/181341246945?hash=item2a38c7d5e1:m:m5IqPuqDvobgAeCZEE6a0ng&vxp=mtr


__________________________________________________
Present: 1991 K100RS "Moby Brick Too"
 
Past:
1994 K75RT "Ilsa, She Wolf of the SS"
1988 K100RS SE "Special Ed"
1994 K75S "Cheetos"
1992 K100RS "Moby Brick" R.I.P.
1982 Honda FT500
1979 Honda XR185
1977 Honda XL125
1974 Honda XL125
1972 OSSA Pioneer 250
1968 Kawasaki 175
    

44Back to top Go down   Fuel in oil Empty Re: Fuel in oil Wed Feb 08, 2017 7:59 pm

Jonas Bodin

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Point-Seven-five wrote:Following this thread I am curious about exactly how much fuel and how quickly it gets into the oil.  Deciliters has been mentioned, but nowhere has the time interval been mentioned. 

Volume and time interval will define flow rate which helps describe whatever the orifice the fuel is leaking through.  Is the tank emptying into the crankcase overnight?  Or is the level creeping up a millimeter or two every couple of days?  Am I the only one who doesn't know this?  Am I the only one who wants to know?

In any event, why not install one of these in the fuel line from the pump to the rail.   That will eliminate the additional head to the tank as well as the large volume available through the siphon effect.

http://www.ebay.com/itm/Metal-Inline-Fuel-Valve-Petcock-5-16-Motorcycle-Fuel-Diesel-Gas-Petrol-/181341246945?hash=item2a38c7d5e1:m:m5IqPuqDvobgAeCZEE6a0ng&vxp=mtr
Hi!

I'm not quite sure about the amount of fuel getting into the oil, but I would say around half a deciliter per run...

Not sure if it occurs during or after the run either!

Have gotten a couple of tips on this forum and I will test to see if any of those tips can help as soon as the bike works again. I'm currently replacing the instrument cluster.

Maybe a valve could lessen the problem, but if it is leaking injectors causing this ordeal I guess I will get the fuel in the fuel rail down in the crankcase anyway?

    

45Back to top Go down   Fuel in oil Empty Re: Fuel in oil Wed Feb 08, 2017 11:09 pm

Holister

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As discussed previously, it would be doubtful that fuel is getting past the rings while the motor is running as any leaking fuel would get burnt off. 
The ingress of fuel to the crankcase is likely after you switch ignition off either thru a leaky injector or possibly via a faulty FPR via the vacuum tube back to #4 TB as suggested above. Residual fuel pressure remains for some time after the pump stops so checking your SPs 10min after ignition off may show you a very wet plug.
As suggested above... checking for evidence of fuel from the fpr vacuum tube would be the first thing I'd try. You just need to power up the pump. Motor does not need to run so you won't need to block the vacuum offtake on #4 TB.
Then after 10min pull the SPs an look for evidence of fuel.


__________________________________________________

1989 K100RT     VIN  0097367 (naked)  
1996 K1100RS   VIN  0451808
 Fuel in oil Austra12    Fuel:  95 Octane
Engine Oil: Nulon Full Synthetic 15W50
Gear Box Oil:  Nulon Synthetic 75W90
    

46Back to top Go down   Fuel in oil Empty FPR ok!? Tue Mar 28, 2017 7:28 pm

Jonas Bodin

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Soo I tested the FPR last week. Pulled of the vacuum hose and turned on the ignition -no fuel coming there! Also tried starting the engine with the vacuum hose off but no fuel now either...

So that's a good thing I guess Very Happy


Leaves the injectors! So what's the best way to check them?


I've already had them out once and couldn't see any leaking that time, but maybe I have to try cranking the engine over a couple of more times? Or perhaps starting the engine and then pull them out directly after shut off?


The search continues!

    

47Back to top Go down   Fuel in oil Empty Re: Fuel in oil Tue Mar 28, 2017 9:54 pm

Laitch

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Jonas Bodin wrote: Leaves the injectors! So what's the best way to check them?
Hollister suggested a reasonable method of finding which might be problematic in post #45 of this thread.


__________________________________________________
1995 K75 90,000 miles
    

48Back to top Go down   Fuel in oil Empty Re: Fuel in oil Wed Mar 29, 2017 5:23 pm

Jonas Bodin

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Laitch wrote:
Jonas Bodin wrote: Leaves the injectors! So what's the best way to check them?
Hollister suggested a reasonable method of finding which might be problematic in post #45 of this thread.
That's right  Fuel in oil 112350

Will start there, but guess I will have to pull them out again anyway! 

What about Ultrasonic washing of the injectors? Could that do the trick?

    

49Back to top Go down   Fuel in oil Empty Re: Fuel in oil Wed Mar 29, 2017 5:31 pm

Motorbike Mike

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I seem to remember pointing toward the injectors on #4, #18 & #21.  Very Happy

    

50Back to top Go down   Fuel in oil Empty Re: Fuel in oil Wed Mar 29, 2017 6:07 pm

Jonas Bodin

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Motorbike Mike wrote:I seem to remember pointing toward the injectors on #4, #18 & #21.  Very Happy
So you did  Very Happy

The weird thing is that they didn't leak one drip of fuel when I had them out... I would have expected to see them leaking a LOT! But I will try it once again:M:

    

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