Air in Fuel

kjjet · **Posted:** Fri Jul 20, 2012 1:13 pm

My CRD is misfiring at idle & driving. Loss of power. So..i had the injectors tested by Pro- performance fuel injection. They found nothing so in inspected the fuel filter housing and found it leaking at the heater plug. At first i had no leak, then i primed and the fuel started to flow out. I would advise anyone checking theirs to press the prime a few times with the plug removed. I ordered the new housing P/N 68043089AA & addapter plug P/N 68043086AB. i am however conserned that i may have somthing else wrong. Dose this leak cause a constant misfire? Thanks in advance!

Hexus · **Posted:** Fri Jul 20, 2012 1:16 pm

As pressurized as that system is, any leak would cause the misfires you're speaking of. This is also a known issue here and lots of people have gone aftermarket on their fuel filter/heater etc.

I plan to change mine out very soon as well.

So yes, that was causing the problem.

kjjet · **Posted:** Fri Jul 20, 2012 2:39 pm

It currently has no CEL or Code. It's running so bad, like its on 3 cyl's along with poping thru the intake. The top of the engine sounds good, so there is no timing issue or rocker damage. I hope it just air???

jkbkwarner · **Posted:** Fri Jul 20, 2012 2:49 pm

I've replaced the fuel filter head on mine and the leak has slowed but has not been eliminated yet. I've purchased a lift pump to create a positive pressure as opposed to the vacuum to draw the fuel. So, I'm assuming I have a leak in the fuel line between the filter head and the fuel tank.

But before I install the pump, I need to get it back from the service garage :dizzy:

Hopefully, they'll solve the random shutdown. My research on lostjeeps is leaning towards the crankshaft position sensor, but the small garage is "busy" and I haven't gotten a status from them yet. :5SHOTS:

kjjet · **Posted:** Sat Jul 21, 2012 10:22 am

Any other input's from our seasoned members? Is this what you would expect from a bad fuel filter head? Thanks!

papaindigo · **Posted:** Sat Jul 21, 2012 10:31 am

Yes and once you install the new filter head prime it using the pump, do not add unfiltered fuel to "help" priming, and follow the instructions on Sir Sam's bleeding video on the NOOB guide although you can use a piece of clear vinyl hose to a catch bottle in lieu of the paper towel. FYI this system bleeds air just like a brake system, pump, open bleeder, close bleeder, pump - if you pump with the bleeder open air will not clear out of the filter head.

kjjet · **Posted:** Sun Jul 22, 2012 9:57 am

Thanks for the input. I will have the parts Monday and will advise. I am also installing a clear hose at the fuel filter exit line to see any air bubbles like the manual states. Hope this gets the CRD back on the road :?:

kjjet · **Posted:** Mon Jul 23, 2012 6:51 pm

Well i replaced the fuel head and installed a clear 3" fuel line to see any bubbles. The jeep starts better now and has no air traveling to the pump. But its still runing bad. I removed the drivers side intake boost hose and the engine is backfiring thru the intake. Like a intake valve is staying open or a exhaust valve wont open. The long and short is... the air in fuel was not the whole problem. Any sugestions proir to tearing it down??? Which i'm so... looking foward to

papaindigo · **Posted:** Tue Jul 24, 2012 8:43 am

What is the mileage on your CRD relative to the required 100,000 mile timing belt change? I hate to think bad juju thoughts but you might want to check your timing which can be done without tearing things down. To do so you will need 3 things Miller 1052 - Intake pin, Miller 1053 - Exhaust pin, and a long handle 6mm allen wrench for a flywheel pin (see the 2005 FSM pg 9-243 for a how to use it - it's a good idea to "tap" around the hole in the flywheel to make sure you are putting the allen wrench in a smalll flywheel hole not one of the larger cutouts.)

If you don't have or have access to the Miller tools do not try to substitute drill bits or allen wrenchs rather get 2 bolts of the proper thread and length (see Miller tool pictures on Sir Sam's NOOB guide and ground bolts at http://www.beesvillebeefarm.com/jeep.html). FYI the diameter of the stepped down tip on those bolts is 0.275" with a bevel for the last 0.08". The bevel helps guide the tool/bolt into the cam hole while the 0.275" section is what locks the cam into place.

See the FSMs or any writeup of the timing belt job on how to lock the cams and flywheel into the correct timed position. Go thru all the steps: 1) if all the pins go in with no resistance and the allen wrench in the flywheel seats per the FSM then your timing should be good but 2) if not you may have to consider, I hope not, jumped timing and rocker damage.

kjjet · **Posted:** Tue Jul 24, 2012 9:42 am

Ya... I just changed the timing belt along with all that goes with it @ 94,000 mile. A full set of new rockers and lifters were installed also. I have all the tools. I just removed the timing cover and everything looks good. I am going to check the timing now and install all the pins. (Flywheel & Cams) If that is good the intake is going to have to be removed. Thanks! I will update my findings.

kjjet · **Posted:** Tue Jul 24, 2012 12:25 pm

The timing is good. (all the pins in and the pump is lined up even the manual states it is not needed) Has anyone checked compression??? It would help point to what cylinder has the valve problem. Thanks

papaindigo · **Posted:** Tue Jul 24, 2012 1:37 pm

When you say all the pins can I assume that was 2 cam pins PLUS the flywheel pin? FYI that fuel pump mark only lines up like every 3rd revolution; how important that is I have no opinion just wanted to note it does not line up on every revolution.

kjjet · **Posted:** Tue Jul 24, 2012 2:10 pm

Correct, 2 cam pins and a 6mm allen wrench for the flywheel. All lined up. Fuel pump lined up and Tensioner is set good. I would like to determine what cyl has the valve open or not problem prior to intake removal. If i can't determine positive problem after the intake is off then i will have to remove the head as well. Even bigger job.

kjjet · **Posted:** Tue Jul 24, 2012 7:08 pm

OK.. I pulled the intake off. Both #1 cyl exhaust rockers broken in 1/2. With everything in time what would cause this? I took a wooden handle and pressed down on the valves and they seem fine. Any clues? Should i pull the head???

ATXKJ · **Posted:** Tue Jul 24, 2012 9:02 pm

Those are the designed break points - should not hurt the valve or piston.
I'd guess your timing was a tooth off on the belt -

kjjet · **Posted:** Tue Jul 24, 2012 9:31 pm

Ya.. I just replaced all 16 due to my timing jump. Only ran for a few days, trying to get the air out. Then it started to backfire thru the intake. The timing is right on and the tensioner was set right on. Anyone have any issues with the new aftermarket rockers from a Member?

GreenDieselEngineering · **Joined:** Sun Jun 07, 2009 5:10 pm **Posts:** 1111

The aftermarket rockers should be fine, the stock ones are not very good as you can see. Is there wear on the rollers and needle bearings or just clean breaks on the stamped steel? The popping out the intake is a good sign pointing to failed rockers, unfortunately there is not a clear diagnosis for this issue.

Check the height on the exhaust valve stems to make sure they are equal. As long as the valves are not bent it should go back together and run well. Glad you found the issue.

kjjet · **Posted:** Wed Jul 25, 2012 8:46 am

Thanks for the reply. All 16 rockers & lifters were just replaced with aftermarket ones. Now both exhaust rockers broke in !/2. Which is better than just bending. When these 2 aftermarket rockers broke the piece droped in by the valve spring. Giving clearance to the cam. Last time (with OEM) the cam ran on top of the broken rocker distroying the surface. I had to install a new cam.

My bigest consern is with all new parts and everything timed correctly, why did 2 rockers bust again? This CRD only has 94,000 miles.

Thanks

GreenDieselEngineering · **Joined:** Sun Jun 07, 2009 5:10 pm **Posts:** 1111

I misunderstood the timing of when the rockers failed. Hopefully those two exhaust valves are not bent, but that would explain the quick failure. Did you use the timing tools when it was put back together?

kjjet · **Posted:** Wed Jul 25, 2012 10:31 am

Sure did. 2 cam pins and 6mm in the flywheel. Cam holding tool all new parts. Ya.. i am a mechanic so i cut no corners. I am however loosing confinance in this engine design.

Thanks

Air in Fuel

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