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

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Sigh.

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

JINX!

Yesterday, on commute, heard back firing on de-cel. Hmm. 
..and mpg avg going from 44+ (unusually high)
..to 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!

Later..

 

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'
to
"Hey, I''m a master tech!"

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

....dcarver

 

 

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.
13321771_10155044550853538_5466914903542

 

JB Weld from ultrasonic tank bottom after cleaning injectors

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

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

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

13269290_10155044547448538_3890362558902

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

13327361_10155044548603538_4438592213399

 

 

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.
13321613_10155055471908538_1472008315547
 
An injector used to live here.
13339730_10155055471913538_4112625907056
 
Like this one. To remove the harness plug from the injector, use a set of hemostats to depress the locking tang.
13343102_10155055471943538_2725392061402
 
Four hopefully dirty injectors causing the rough running and decel popping.
13393908_10155055471963538_1950710460141
 
This is the spacer I alluded to earlier.
13394093_10155055472003538_7382015030078
 
This stuff works great on elec connectors.
13346956_10155055472033538_6517726836334
 
I bought this tube of syn grease when I was at NERDS in Vermont. It reminds me of good times.
13332751_10155055472108538_8350432167684
 
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.
13325650_10155055472123538_7101580108598
 
13339695_10155055472138538_4970157408670
 
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
 
..to 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.
13394139_10155055472178538_7664771575168
 

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.

13332940_10155055472228538_1533294568361

 

The pump, out  of the tank.

13322097_10155055472273538_5266709269416

 

Time to flush the tank.

13321827_10155055472318538_6752734264671

 

13393967_10155055472368538_1423401839038

 

https://www.facebook...55055459688538/

 

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

13406727_10155055472448538_7387596655710

 

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

13343159_10155055472473538_2956212478910

 

After 10 or so flushes.. finally looking good.

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Time for one last vertical flush.

13339567_10155055472568538_5367772524986

..to 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..

13406707_10155055460093538_7476381215876

 

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

https://www.facebook...55055460133538/

 

No comments from the peanut gallery...

13321755_10155055460558538_6352784456743

 

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

13335659_10155055460573538_5022686142533

 

Level indicator assembly

13335979_10155055460628538_3325764044801

 

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

https://www.facebook...55055460668538/

 

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

13339669_10155055461113538_3004578684238

 

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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