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1Back to top Go down    throttle balance - bike won't go again... on Thu Oct 05, 2017 5:01 am

Cablebeacher


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Hi all

1. Fuel tank rubber belt and motor died.
2. Replaced them and all filters. New injector filters and o rings
3. Checked bike shim timing. All great
4. Replaced all fuel hoses. Breather hoses etc
5. Clean healthy new petrol. 95 octane
6. Bike going great. Tried unsuccesfully a couple of weeks ago to balance the throttles with clear tube DIY manifold. Couldn't get it to work. Lost interest.
7. Took it to the local only bike shop to get them to balance the throttles.
8. Get a call from him
9. Bike balanced fine. Then had lunch and it wouldn't start. Put the fuel settings back to where the were but bike now won't start...
10. I went over thinking it could simply be the undertank fuel pump connector. It wasn't...

12. Fuel pump works. Pumps petrol through the filter in tank after the filter. Fuel return at injector rail pumps fuel.
13. Spark plugs fire. Tested with repair shop tester.
14. Fuel injectors pulse. Tested with shop tester.
15 Battery charged. All Fuses ok.
16. Checked fuel injection box for secure connection.
17. Checked speedo wiring loom to find two broken pins. Ascertained they are for choke and illumination - so assume insignificant...

18. When i asked about the re-setting of the balance of the throttles the shop owner said he "thought he had mucked up the settings as it wouldn't start. I screwed the four adjustment screws all the way in and then out 1 1/2 turns on all them".
19. His gun mechanic is away until tomorrow. I am also 2,200 kms from BMW in Perth and 1,900 kms from BMW in the other direction...

We have double checked everything and I am thinking it is the fuel balance settings.

Any ideas?

Thanks

Mal

    

MartinW

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Remove the spark plugs and see if they are wet or dry.
Regards Martin.

    

92KK 84WW Olaf

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Can you clarify is bike firing or trying to fire when you are holding the start button down and then cutting out or not firing at all when you hold the start button down?


__________________________________________________
1992 K100LT 0193214 Alaska Blue 101,000 miles
1984 K100RT 0022575 Baja Red bought 36,000 now 89,150 miles
1997 K1100LT 0188024 Mystic Red 58,645 now 80,700 miles
    

charlie99

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hmm nothing said about fuel pressure from the pump

are we sure that there is actually some fuel getting to the injectors ...and at the right pressure

we have seen many times that the internal fuel lines have either split or the fuel filter is chockers with gunk

my best guess is that the high pressure line from pump to filter ...then to outlet has perished - leaking ? and loosing pressure

or perhaps you have been unlucky and pumped some crud to the filters ontop of the injectors ...now not passing fuel through them ?

just a thought to check


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

'86 K100 RT..#0090401 ..."Gerty" ( Gertrude Von Clickandshift ) --------O%O
    

RicK G

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If the brass screws are 1 1/2 turns out then that is around where the correct setting would be and considering Broome's climate I doubt that a very cold start is causing a problem. As Martin said check the plugs if they are wet that means the injectors are working. Unplug the pump at the tank and plugs out wind the motor over for about a minute then new plugs and pump connected hit the start, there is a good chance it will start.
If that doesn't work put some oil in the bores and unplug the pump wind it over to spread the oil around then give it another go. The Nicasil bores will become oil free after a wash with fuel and you can get very low compression. I haven't seen it very often with the bikes but the BMW cars with the nicasil bores are renowned for it. I have bought 3 cars very cheap because they wouldn't start and had no compression.


__________________________________________________
"Every normal man must be tempted, at times, to spit upon his hands, hoist the black flag, and begin slitting throats." from Mencken's 1919 Prejudices

Bikes 1993 K1100 LT, 1998 K1100 LT, 1993 K75 RT, 1996 K75RT, 1986 K75 GS, 1979 Z1300 Kawasaki X 2 for now
    

Point-Seven-five

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+1 on flooding. I have had a couple of floods with my bikes recently. It seems that when trying to start a cold engine, if it doesn't fire immediately the injectors will soak the spark plugs and it won't spark, allowing the injectors to keep filling the cylinders with raw fuel.

I cleared mine by just disconnecting the tank connector and cranking the engine for about 30 seconds or so with the throttle open until it tried to fire a few times. This seems to clear the excess fuel from the cylinders. Then reconnect the tank plug and it fired right up. Has worked for me twice now.


__________________________________________________
Present:
1994 K75RT
1994 K75S
1992 K100RS

Past:
1982 Honda FT500
1979 Honda XR185
1977 Honda XL125
1974 Honda XL125
1972 OSSA Pioneer 250
1968 Kawasaki 175
    

Cablebeacher


Silver member
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@92KK 84WW Olaf wrote:Can you clarify is bike firing or trying to fire when you are holding the start button down and then cutting out or not firing at all when you hold the start button down?

Hi Olaf

The start button is working fine. It tries to fire continuously until you stop pressing...

The two KILL switch positions also work as normal.

Regards

Mal

    

Cablebeacher


Silver member
Silver member
@charlie99 wrote:hmm nothing said about fuel pressure from the pump

are we sure that there is actually some fuel getting to the injectors ...and at the right pressure

we have seen many times that the internal fuel lines have either split or the fuel filter is chockers with gunk

my best guess is that the high pressure line from pump to filter ...then to outlet has perished - leaking ? and loosing pressure

or perhaps you have been unlucky and pumped some crud to the filters ontop of the injectors ...now not passing fuel through them ?

just a thought to check
Hi Charlie

The fuel pressure was pretty high in the tank and at the rail. It has a brand new fuel filter and pump.

The tank is spotless due to the disintegrated old rubber fuel boot. Don't think at this stage it is a fuel block.

All the fuel hoses were replaced.

Regards

Mal

    

Cablebeacher


Silver member
Silver member
@RicK G wrote:If the brass screws are 1 1/2 turns out then that is around where the correct setting would be and considering Broome's climate I doubt that a very cold start is causing a problem. As Martin said check the plugs if they are wet that means the injectors are working. Unplug the pump at the tank and plugs out wind the motor over for about a minute then new plugs and pump connected hit the start, there is a good chance it will start.
If that doesn't work put some oil in the bores and unplug the pump wind it over to spread the oil around then give it another go. The Nicasil bores will become oil free after a wash with fuel and you can get very low compression. I haven't seen it very often with the bikes but the BMW cars with the nicasil bores are renowned for it. I have bought 3 cars very cheap because they wouldn't start and had no compression.
Hi Rick and Martin

It is now tomorrow! I am on my way over to the bike shop. I have thought (during the night!) that it may well be a flooding issue. Actually HOPING it is...

Will try the PLUG OUT CRANK method. Plugs are fine with gap etc and were firing yesterday when we checked it. It may have actually dried out overnight???

Does anybody know if there is a "computer plug" that gives access to the fuel injection brain box? The BMW bloke in Perth (2200kms away) said there should be one with a BLUE cap on it. I have never seen one and have never come across mention of one on this forum. Any ideas? There is another K100 in town and I may try to get him to swap a couple of bits.

OTHER QUESTION: could it be any of the electrical relays under the fuel tank?

Regards to all

Mal

    

RicK G

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I doubt it would be the fuel injection relay because it makes the pump run as well as EFI. Be sure to disconnect the pump when spinning it over to dry it out or you just put more fuel into it.


__________________________________________________
"Every normal man must be tempted, at times, to spit upon his hands, hoist the black flag, and begin slitting throats." from Mencken's 1919 Prejudices

Bikes 1993 K1100 LT, 1998 K1100 LT, 1993 K75 RT, 1996 K75RT, 1986 K75 GS, 1979 Z1300 Kawasaki X 2 for now
    

11Back to top Go down    Why I hate things mechanical (sometimes) on Fri Oct 06, 2017 12:43 am

Cablebeacher


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Having gone through all the options through the middle of the night when I should have been asleep I am once again astounded by this forum...

This morning I read the replies to my list of woes and concurred that the only thing I hadn't checked was the "flooding" option. This morning at the bike shop it fired up! Obviously dried out overnight. I didn't think of the flooding yesterday as in the past when it has happened there was a big smell of fuel about the place.

They balanced the fuel settings, took it for a test and were happy. It flooded again. So they checked and replaced the spark plugs. The mechanic (who wasn't there yesterday) thinks the centre electrodes were not completely flat thereby "possibly" shorting the spark to the side of the plug, getting wet with fuel then causing flooding... Put in new plugs.

Rode it home, swore at it and nearly kicked it.

Thanks for all the valued and valuable input from everyone.

Mal

    

nino


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I had a similar symptom few days ago. Spining strongly but not firing. I removed the fuel rail with injectors, hit the button and realize no fuel from injectors at all. To make story short - it was faulty temperature sensor. No signal to injectors.
When changed sensor engine started normally.

    

Point-Seven-five

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No need to spend the time to pull the plugs, just crank the engine for 20-30 seconds with the tank connector unplugged and the throttle open to blow the fuel out of the cylinders.


__________________________________________________
Present:
1994 K75RT
1994 K75S
1992 K100RS

Past:
1982 Honda FT500
1979 Honda XR185
1977 Honda XL125
1974 Honda XL125
1972 OSSA Pioneer 250
1968 Kawasaki 175
    

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