Its been a busy arvo here in the "HesmadLab".

On our Tuesday ride I was handed some injectors for Blakey by K-Freak. "they wont fire, but you might be able to" so i took up the challenge. I read up on how the injectors work and set about trying to free em up.

I first Numbered the injectors and checked the coils and they all measured in at 16 ohms. Good.

Next i hooked up my trusty power supply and tried to fire em. Nothing, Notta, zilch>>>>>
So I fired up my super youbeat ultrasonic cleaner and gave them a short bath.

After the first short bath i tested each injector and one actuated. set this one aside and put the rest back in the bath and continued with testing and ultrasonics untill they all actuated.

Now a brief trip to youtube to see how people were cleaning the gunk out from the insides. Here is what I found. Use a can of carby cleaner, short lenght of fuel hose and 30ml syringe.


I set up the first injector and pressurised the cleaner and powered up..

Not the best. So gave it a few more after lewtting it stand with cleaner in the injector and ...

Out came a splutter then whoosh!!!
Nice round pattern on bench top..


So now all they need is some new filters/caps/o-rings ect as they are all working nicely on the bench. I am more and more impressed with ultrasonics as a mediem for cleaning small tight places. (thanks OG!!) So if you are coming up on the 7th bring those pieces to clean as I have a fresh bath of cleaner.

I suspect if you wired them up to the previously discussed energiser circuit and had them firing whilst submerged in the ultrasonic bath it would be even more effective at removing the gunk from inside.
Regards,
K-BIKE

nice work there alby .....thumbs up

Wow, thanks for that!
I'll pay for the can of carby cleaner!

Oh man. I have 8 of those sealed up injectors laying here right now. Wish I had access to an ultrasonic cleaner...

Alby,
What liquid was used in the sonic cleaner

Ungass Brulin 815 GD is a standard immersion and ultrasonic detergent cleaner. I used it in its weakest solution. My cleaner has a peak of 500 watts.
K-Bbike i had a look for the timer you mentioned (I remember reading it) but cannot find it. I agree it would be more efficent to have a timer and being able to adjust the duty cycle would give an accurate reading of coils performance if flow rates were measured. Best go pinch the neighbors rain-gauge!

blakey..Its on me, just be here on the 7th!!

The article was about using a 12 volt rectified AC to give a wave form that would fire the injectors open and shut so as to work them. Seeing your article it occurs to me that having them cycling whilst in the ultrasonic bath would help the sonic waves penetrate from both ends.
Regards,
K-BIKE

K-Bike yes . It would help to have the injector open to allow the cavitation process to lift the rubbish from the valve seats. The great thing about ultrasonics is the sound will resonate through the item in the bath. so anywhere there is liquid the cavitation (cleaning process) will occur.

some of the battery chargers are half wave rectified .....good shaking ability of batteries ...and a good operation of injectors i suspect equivalent to 3k ?

Cheers for that, some good info.

Thats a good write up Alby thanks for sharing that.

BIG D

Found this on Oz Fleabay.

I believe this kit will be what I'm after to bring them back to near original...and have a spare set.

Also, on YouTube, there are videos on how to change the filter.

good link blakey, he has all sorts of good things ..

That looks simple enough. Ill go you halves in the kit Blakey. I got four spares i want to clean up.

Nah, my shout for cleaning the injectors.

Bought four K1100 injectors with higher flow to replace the standard ones on my K100. So, I got into cleaning them based on the instructions above. Below, I document the differences:

First, I couldn't get ahold of a syringe that tightly fit the fuel hosing I had lying around so I used a vacuum plug instead.




I cut the hose and press fit a rubber vacuum plug in the end after piercing a hole in the end of the plug with a jeweler's screwdriver so that a spray nozzle was a tight fit. As you can see, the setup works well for spraying carb cleaner through the injectors.


I built a very simple wire to actuate the injector. Lamp cord with one line cut and spliced in a push button switch. I found a Bosch injector connector pigtail by raiding a car at the local junk yard and cutting a connector off its wiring harness. Soldered and shrunk wrapped the connections.


Aso found this simple circuit online which exercises the injectors like professional test instruments. It could be built for $20-$30 in parts. It's overkill for this application however but may be interesting for others here.

Bought an 8 cylinder rebuild kit from Mr. Injector to recondition the replaceable injector parts (therefore I have parts for the K1100 injectors as well as the original K100 injectors). I'll give the injectors an ultrasonic bath in Simple Green solution, replace the parts and spray paint the bodies with heat resistant paint. They'll look and work good as new; and it only cost me $40 for everything including the injectors. Not bad.

nice !!!

I just purchased a fuel injector flow bench and test machine. I am now offering as a service cleaning and testing fuel injectors. I also have in stock new O rings and filters for the BMW injectors. Some people on here have cleaned their own injectors but with out the flow bench you can not be sure if they are working correctly. Also with the ethanol in the fuel some of the old O rings are getting beat up. The new O rings can handle the new fuel additives. Also there is a screen in the top of the injector which over the years gets clogged and can estrict fuel flow thru the injector. If anyone wants more info about my service or just needs replacement O rings and screens let me know.

Is there a website from where to buy these refurbishment parts?

There are a few guys on ebay selling the parts. I also have parts avaliable for the do it yourselfer. The only way to be sure the injector is working corectly is on a flow bench. You can get them to have a good looking spray pattern but you cant be sure they are all flowing the same amount of fuel. Also it would be hard to leak test them. I run full operating pressure thru the injector for 30 seconds and see if there is any dripping. The cost to have 4 injectors cleaned is $60. That is $15 per injector. If you want more info feel free to contact me.

Very nice example!!

RJTrucker

This sounds an excellent service.

I am thinking could you set up an exchange service that we could use from abroad. The cost of the work is reasonable, even for us the cost of postage is not high as the injectors are light enough.

The way these would work is we order injectors, pay for them including a deposit which would be refunded when you are in receipt of the old injectors....That way no one is off road for long.

We have same over here for exchange fork stanchions etc.

I would be willing to do it on an exchange basis. I do whave a few sets of injectors here that I can make ready. The only other issue would be if I am sent an injector that has a bad coil in it of if I am sent an injector that can not be restored. Then I would have to charge for the replacement injector from the deposit.

Hello Gents,

This topic and discussion hve been very useful. I thank you for this.

I often hear that injector must be calibrated, is this correct? This is to measure the amount of fuel comes out in a given time.

The expert comment / view is much appreciated.

Best regards.

There are no adjustments on an injector. They are sealed. On my flow bench I can measure the amount of fuel released over a selected time and fuel preasure. When I have a set I run them and make sure they all are within 1% of each other. The main thing is getting them clean inside the chamber and the pintle valve. Dirt in the valve can cause leakage and an irregular spray pattern. Dried fuel can coat the inside of the chamber and restrict fuel flow. Also the screen can get clogged just like a fuel filter. The yellow pintle caps only function is to protect the pintle valve. If you look closely you can see a small pin sticking oit of the injector. Do not touch that. If damaged the injector will not function corectly. Also the new o rings are made to be able to take the new fuel additives. I hope this helped. If you have any other questions I will try to answer them.

Hi Rjtrucker,

Thanks for the explanation. I understand that the meaning of calibration is actually cleaning the injector and check the amount of fuel comes out of it.

Cheers

https://youtu.be/rUUgR94drxg

Just did this! Tire Valve stem Worked great and if you use the right drill bit there is no need to melt the 2 together. And drill the cap with it screwed on, then your hole will be dead center 👊🏿

I also found a dead injector which will like diagnose why I was in there cleaning them in the 1st place. 

Genius Kurus (k bike gurus) will any k injector replacement work 85-91?
Now having 3 functional, freshly clean ones...it seems excessive to buy a new set from eBay.

Any if anyone local has one I'd love to get the old girl screaming again.

MikeisonTV wrote:Genius Kurus (k bike gurus) will any k injector replacement work 85-91?
YES, up to 1996

Now having 3 functional, freshly clean ones...it seems excessive to buy a new set from eBay.
You could buy this injector set, they are perfect for the K.
put them for two hours in brake cleaner and sell the unneeded or clean as shown above.
Now you will have the modern four hole injectors :-)
Bosch Fuel Injector Set of 6 for BMW 2.5L 3.0L Part # 0280150415 / 0 280 150 415
It has to be the Bosch number / 0 280 150 415

Cheers

While the #415 will work and you probably won't notice any difference in performance, by my calculation they will deliver slightly less fuel so your induction will run a little lean. Slight over heating may occur. Check SPs for colour. Changing to a cooler plug (D8EA) may help.

Read THIS

Must state up front, I don't have the answer and was fishing for one:

Basically:

1. Pull the whole fuel rail out with injectors still attached.
   
2. Then put the bottom ends of the injectors into test tubes with measurements on the sides (all are sitting in a secure test tube rack)
   
3. Use the starter button to turn the motor over and have all injectors working at the same time for the same amount of time. Make sure this is done in 10sec or so intervals (no longer than 20secs) - total time 60secs
   
4. Compare quantities to identify if flow rate is the same.
   

Any suggestions or improvements?

My bike has vibrations and I want to check if injectors are flowing the same.

Graduated test tubes:
https://www.ebay.com.au/itm/5-50ml-Lab-Clear-Glass-Test-Tube-Round-Bottom-Graduated-with-Screw-Cap-5-50Pcs/153289573489?hash=item23b0c54471mF2EXwi5_g-nAbaKo_QFcFA

Guy

You can get graduated vessels from the local home brew supply shop. Injector pulsars are available off Ebay and Aliexpress. I made an air powered test rig to run at 35 PSI out of a used gas bottle, a lot safer with a highly reduced chance of setting fire to anything. The pulsar allows precise  timed runs so you can do one injector at a time for accurate comparison. The glass graduated vessel allows easy viewing of injector patterns. The initial plan had a homemade battery and switch which was replaced by the commercial pulsar.
Regards Martin.

That's impressive Martin. Thanks for the pics

Re: Fire: if the engine was cold then exhaust would be cold and no threat of fire.

However, does it make a difference to injector flow rates if the injector is "warm" / or in an engine at operating temp? 

My bike seems to settle in after about 10 mins and the vibrations get less (or I get used to them).

On the fire front, I was riding a BMW R65 in traffic and while waiting at the lights I could hear sizzling. The in-line fuel filter had split and fuel was dripping on the hot exhaust. So I rode the bike to the nearest garage, leaning it over as much as I could, and put a car filter onto it. My friend who possesses a pedant's knowledge of many things, said that the metal was not hot enough to ignite it ... a flame or spark is needed. So no explosion of flame and smoke in the morning's peak hour traffic that day.

Guy

A few Brickers have set fire to their bike while testing their injectors on their bikes. Probably due to an errant spark from their leads. All the testing I've done and seen at injector shops is done at room temperature. Engines are designed to run at a set temperature and some will not run perfectly until optimal temperature is reached.

 I built my injector rig chasing a backfire on overrun. I did all the other tweaks and tests and it came down to what I believed was a incorrect pattern. I'd previously had my injectors supposedly professionally cleaned and tested with no improvement at $90.00 AU per set. I thought I had nothing to loose by doing it myself. The rig with the pulsar, cost me under $90.00AU and once tested I new I was on track the patterns were all different. Once cleaned the and flow tested the result was definitely felt on the road and no more backfire.

When doing your injectors it is important to replace the small filter screens that reside in the inlets of the injectors. They are often overlooked, to remove them screw in a self taping screw large enough to grip the screen. Then with a pair of vice grips pull out the screen, which will now need replacing. Link to tester.https://www.aliexpress.com/item/Professional-fuel-system-scan-tool-Injector-tester-4-pluse-modes-tester-powerfull-fuel-injector-all-sun/32706991699.html?spm=2114.search0204.3.93.52a97f82kr4aZa&ws_ab_test=searchweb0_0,searchweb201602_6_10065_10068_10130_10890_10547_319_10546_317_10548_10696_453_10084_454_10083_10618_10307_537_536_10131_10132_10133_10059_10884_10887_321_322_10103,searchweb201603_90,ppcSwitch_0&algo_expid=0ed453cd-2c7d-4e81-b2e2-f2c430a9e2f9-14&algo_pvid=0ed453cd-2c7d-4e81-b2e2-f2c430a9e2f9&transAbTest=ae803_4

I've often spun the rail around to check the injectors spray,  but you need to disable the coils,  or somehow prevent the possibility of the spark from the plugs causing a fire through the hole where the injectors were. A bloke I know lost a valuable boat that way. Maybe temporarily fit a spare rail with injectors.

I have no desire to burn down my garage(and house) testing injectors.  Atomized fuel mist scares me when it's not in the engine.  That's how they make those huge explosions you see in movies.

A couple times a year when I have about a half tank of no-ethanol fuel I will dump in a 12 ounce bottle of Techron Fuel System Cleaner(any good cleaner will do) and run the engine for 5 minutes.  Then I let it sit overnight.

Next day, I take the bike out for a good hard ride for an hour or so.  Another night, and repeat. 

Fixed a bad running 16V K100RS that way.  No problems with any of my bikes over the past 4 years and 60,000 miles that I have been doing it.

Every year or two I used to throw a bottle Techron in my Brick. But not until I actually cleaned them myself  did I eliminate the all the backfiring. I have a spare set of cleaned  injectors which I'll rotate through the bike if & when backfiring returns. I'm not sure if I will keep using the Techron, BP have a Hi Octane fuel with a built in cleaner. I might just use a couple of tanks a year of it and see how it goes. I personally would never try to clean injectors while installed. My test rig is totally air powered to eliminate the risk of BADDA BOOM.
Regards Martin.