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2016-03-31 Running Rough just above idle - dirty fuel injectors



3 days ago the thought crossed through the cranium scareabellium how wonderful KrZy8 was running.


Yesterday, on commute, heard back firing on de-cel. Hmm. 
..and mpg avg going from 44+ (unusually high) 28 mpg (unusually low except if at go-to-jail-speed)
..and back and forth.

So, stopped by Chevron (my top-tier provider of choice), added 8.7 gallons to main and aux tank.
Purchased a bottle of 'Techron' and dumped all into the 6.6 gallon main tank.

Rode home, added SeaFoam, 3/4 bottle to Aux tank.

After just under 200 miles, (and mixing Aux tank SeaFoam with main tank Techron as the gauge dipped), she WAS running a *bit* better. 

Main symptom? Transitioning off idle up to 3k rpm.

Idle, stable.

MPG - all over the place.

Firing misorder very evident from left bank, cylinders 1 or 2 as evidenced by placing hand at left exhaust. Can't be missed. Substanital.

Ok then. 

Bike home, removed all plugs. All look good.

Removed fuel rail.

Going to replace injectors, 1, 2 with spares I have laying around.
Will replace 1, 2 sparking plugs too. 
I care less about what's wrong than just getting her fixed.

That is why I'm not an engineer... LOL.

Root Cause?
Good question.
My best hypostehsis is this-
My Aux Tank had an aluminum baffle cross-welded in on each quadrant. Only tack welded, which broke.
I attempted to fix by using JBWeld for gas.
Which broke free.
3 - 4 inch sections of JBWeld broke free after years of riding the dirt road back home.

The aluminum baffle plate, no longer secured, rotated to a postion where the JBWeld was rubbing against a section of the interior tank. The JBWeld was visibly reduced by the rubbing; from approx 5mm 'bead' to half that.

And all that JBWeld went somewhere.

I don't have a fuel filter between the aux tank and main tank.. but will have one by end of day tomorrow.

Will test the 2 injectors removed from KrZy8 tomorrow using a DIY homebrew method.

...and also test 2 injectors from the 'old' rail too.

Should be fun!



Today, removed fuel rail and tested injectors using a syringe full of brakekleen and a 12 volt battery. On the left bank, found one injector kinda droopy in the spray pattern as compared to the other 3. Interesting to note there are 4 holes in the injector, only two appear to spray, even on a brand new injector.

Replaced fuel rail, started, popping not cured. Just off idle. 

Removed rail, shot brakekleen through rail, then blew rail clear with compressed air.
Changed all plugs with some I had laying around. Irididum to 'normal' plugs. Whatever.

Changed air filter, even though the one installed was not all that dirty. Very serviceable, actually.

After each change, started. And no change. Still popping, badly.

In the process of installing the new air filter, noticed wires going to sensor measuring air box press or temp, not sure which, were being crimped by the air box cover. Shit. That ain't good. Removed the x-brace and re-routed the wiring.

I don't know why - but she suddenly just started running right.

Noticably right. As in Vrooom-VrooooooM!

So, I guess I'll go with it.

From 'take her to the shop, fuck it, I'm done'
"Hey, I''m a master tech!"

...more to come as the miles roll on.




Posted 01 June 2016 - 12:08 PM

EDIT - These pix are stored on FaceBook servers. I have originals stored on CBA server should FB fold...

Removed injectors from KrZy8.


JB Weld from ultrasonic tank bottom after cleaning injectors


One injector was really bad. This after the bath and using air to backflush through injector past inlet screen.



After ultrasonic bath. I used a 9 volt battery to actuate the pintel.


Yes, put 4 in a bath, get 5 back. I have 12 injectors and 3 rails in the inventory now..


Don't look, it will poke yer eye out!




Hopefully this weekend will have time to reinstall and test fire KrZy8.

Posted 06 June 2016 - 09:46 AM

EDIT - These pix are stored on FaceBook servers. I have originals stored on CBA server should FB fold...

Ok then, how to replace clogged injectors. Loosen the the top fuel rail, 3 screws. Don't lose the two spacers on each end, bottom side.
An injector used to live here.
Like this one. To remove the harness plug from the injector, use a set of hemostats to depress the locking tang.
Four hopefully dirty injectors causing the rough running and decel popping.
This is the spacer I alluded to earlier.
This stuff works great on elec connectors.
I bought this tube of syn grease when I was at NERDS in Vermont. It reminds me of good times.
The gas tank is contaminated with JB Weld particulates. The JB Weld patch I used on the aux tank baffle plate broke, the jb weld rubbed against the sharp edge of the lower baffle... very tiny particles.
I mark the housing, even though it's damn near impossible to install it wrong.
Some folks have been able to remove the pump as one unit. I can't figure out how they did it. You can see the tang won't clear the hole.
13394139_10155055472178538_7664771575168 be continued.

Posted 06 June 2016 - 09:55 AM

EDIT - These pix are stored on FaceBook servers. I have originals stored on CBA server should FB fold...

Some folks have been able to remove the pump as one unit. I can't figure out how they did it. You can see the tang won't clear the hole.

The way I remove the pump is to remove the level indication assembly from the fuel pp body.
Press the tang, then gently push the assembly downward.



The pump, out  of the tank.



Time to flush the tank.







The floaters are all JB Weld remnants. This is AFTER 2 flushes.



Time to get serious. A little dishs soap goes a loooooong ways.



After 10 or so flushes.. finally looking good.



Time for one last vertical flush.

13339567_10155055472568538_5367772524986 be continued.

Posted 06 June 2016 - 10:07 AM

EDIT - These pix are stored on FaceBook servers. I have originals stored on CBA server should FB fold...

Here's what was coming out of the tank. This is not dish soap..



Time for a blow job.. to dry the tank..



No comments from the peanut gallery...



Close up views of the fuel pump. I wonder how gallons this puppy has pumped over 200k miles?



Level indicator assembly



The big test.. Will she start? Will she run OK? If not, I don't know what else to do..



200k + miles.. Still looking and running good!



Many thanks to FjRay who convinced me to do the job correctly the first time.. in other words, to remove the fuel pump in order to thoroughly clean the tank. I had talked myself out of it - too much work. After seeing the severity of contamination, I'm glad I did.


Rode KrZy8 to work this morning. About 55 miles. She runs GREAT! MPG went from 23 - 25 to 38 - 41. WooHoo!

She's running great! MPG is up better than ever, right at 40, from 28-32...

Read RR here!

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