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-   -   IP Timing: Need Some Advice (http://www.peachparts.com/shopforum/diesel-discussion/356710-ip-timing-need-some-advice.html)

npretnar 06-28-2014 01:53 PM

IP Timing: Need Some Advice
 
So over a year ago, I pulled the IP and the Oil Filter Housing to replace a bunch of leaky oil seals. I put it back together and timed it to 26 - BTDC. The car ran okay after that, though there was a shake at idle I never could get rid of, not even after new motor mounts and shocks, new injectors and a new rack damper bolt.

I figured it was slightly miss timed. So I set the crank to 24 this time, pulled the pump again yesterday and set the tooth marks to speck and then replaced. Drip timed it to 1/sec, at WOT. Replaced fuel filters (both) and bled the lines accordingly. Started car and it ran rough for a second, which is expected, spewing smelly, (unburnt fuel) white smoke out the back. It smoothed out slightly, but now there is a very pronounced miss (in fact often times multiple misses) at idle. Sometimes, it won't even stay running, when cold, and shakes ferociously.

When hot, it doesn't smoke but exhaust still smells awful. Acceleration is the same as before and will do 70 easily. On deceleration in first or second gear, however, (under 15 mph) you can feel the car shaking while in D, and you can hear the engine kind of missing/loping. At idle, the miss/lope is extremely noticeable. Adjustment of rack damper bolt yields no improvement.

This definitely is a fueling issue. My question is, is the IP shot? What about the possibility that delivery valves are sticking or damaged?

Diesel911 06-28-2014 02:57 PM

Was it shaking at Idle before you removed the Fuel Injection Pump and replacing it and retiming it made it worse?
And did the Car sit for a long time before you got it back together?

Adjusting the Valve sometimes fixes a shaking Idle.

If I did this on mine and the Engine was running good before I removed the Fuel Injection Pump and it started after I reaplaced and re-timed it.
I would fist look for stuff that might cause an Air leaking into the Fuel Inlet; including the Old Style Hand Primer if you have one.

If none of the above was wrong I would be re-timing the Fuel Injecion Pump or you if there is no mark already on the Engine that goes acrossed the Fuel Injection Pump Flange so you know where you started at you could experiment with rotating the Fuel Injection Pump tiny bit and tighten it down and go for a drive and when you come back see if it changed the Idle.

If you don't keep the Fuel Pressure even during drip timing the amount of drops/drips is going to change and you cannot count on them.

npretnar 06-28-2014 08:09 PM

It was shaking, but not severely, before retiming it. Hence, the reason for wanting to retime. Valves were just adjusted last month and none were too bad out of speck.

When I went to time it this time, I never reached the point on the swivel where no fuel was coming out of the drip tube. That leads me to believe that the splined notch may not have been aligned right. But the engine was at 24BTDC with the cam ears pointing up. I'm wondering if somehow my timing chain is badly off. Would this be a symptom of such an issue?

Diesel911 06-28-2014 09:57 PM

Quote:

Originally Posted by npretnar (Post 3350696)
It was shaking, but not severely, before retiming it. Hence, the reason for wanting to retime. Valves were just adjusted last month and none were too bad out of speck.

When I went to time it this time, I never reached the point on the swivel where no fuel was coming out of the drip tube. That leads me to believe that the splined notch may not have been aligned right. But the engine was at 24BTDC with the cam ears pointing up. I'm wondering if somehow my timing chain is badly off. Would this be a symptom of such an issue?

When you stick the IP back into the Engine the Studs need to be centered in the Kidney Slots on the Flange or you can run out of adjustment during timing.

Your Timing Chain may or may not be worn. But, when you retime the Fuel Injection Pump you are timing it to the Crankshaft Degrees so as far as the Injection Pump Timing goes you have compensated for the Timing Chain Stretch.
Resetting the Fuel Injection Pump Timing does not change the Engine Valve Timing that is also effected by the Timing Chain Stretch.

When I had Hot Idle Shaking it was doing the Valve Adjustment and rebuilding the Injectors with new Nozzles that fixe like 85 percent of the Problem.
The Stock Bosch Injector Nozzles have some tiny passages in them that get plugged with Carbon and those passages are where the Idle Fuel is supposed to pass through.

I posted a whole bunch of pics of the diagrams on that over the years.
If you look in one of the threads that has the question which Injector Nozzles to buy I think you will find some of My pics.
DIY Repair Links
http://www.peachparts.com/shopforum/forumdisplay.php?f=82
http://www.peachparts.com/Wikka/DoItYourSelf

masc243 06-29-2014 08:27 AM

I solved a similar issue by soaking the pipe holders in brake fluid for a week. The pipe holder is the piece that is removed on #1 to do the injection timing. Go ahead and pull each connection with the associated spring and plunger element and soak them. You'll not that the pipe connection has a tiny orifice. There is actually a spring type device inside that helps to avoid secondary combustion from the fuel shock wave traveling back down the injector line after the injector closes, (Or something like that).

At any rate, the orifice is quite small in diameter and any clogging here will affect idle quality.
Mike

npretnar 06-29-2014 02:31 PM

Cleaning delivery valves
 
Masc,

Did you clean all of the components of the delivery valve assembly (Spring, valve, little thingy under Spring inside hollowed out cylinder thingy (pardon the technical jargon)? I may try soaking all of these parts. I don't need the car anyway for at least a couple of weeks. I just want it running again.
Also, did you label which parts go with what, so as not to mix up the components of the various assemblies?

masc243 06-29-2014 02:42 PM

Quote:

Originally Posted by npretnar (Post 3350937)
Masc,

Did you clean all of the components of the delivery valve assembly (Spring, valve, little thingy under Spring inside hollowed out cylinder thingy (pardon the technical jargon)? I may try soaking all of these parts. I don't need the car anyway for at least a couple of weeks. I just want it running again.
Also, did you label which parts go with what, so as not to mix up the components of the various assemblies?

Yes I cleaned all of the parts you mentioned; note that i cleaned the parts previously with little effect. It was the pipe holder that received the extra attention and what changed the idle quality for me. Eaton9999 also had a similar idle shake that solved his problem the same way, but i believe he changed his from a j-yard pull.

I didn't track which came from which d-valve and jumbled them all in the same container.

Its been a couple months since i cleaned mine and cleaned up the idle tremendously; I will likely do one more diesel purge and perform one more cleaning in the near future. I think the PO may have experimented with wvo. Might be wrong, but my tank screen was filled with muck as well.

Mike

Diesel911 06-30-2014 12:53 AM

Quote:

Originally Posted by masc243 (Post 3350823)
I solved a similar issue by soaking the pipe holders in brake fluid for a week. The pipe holder is the piece that is removed on #1 to do the injection timing. Go ahead and pull each connection with the associated spring and plunger element and soak them. You'll not that the pipe connection has a tiny orifice. There is actually a spring type device inside that helps to avoid secondary combustion from the fuel shock wave traveling back down the injector line after the injector closes, (Or something like that).

At any rate, the orifice is quite small in diameter and any clogging here will affect idle quality.
Mike

Pipe Holder = Delivery Valve Holder

Diesel911 06-30-2014 01:01 AM

Quote:

Originally Posted by npretnar (Post 3350937)
Masc,

Did you clean all of the components of the delivery valve assembly (Spring, valve, little thingy under Spring inside hollowed out cylinder thingy (pardon the technical jargon)? I may try soaking all of these parts. I don't need the car anyway for at least a couple of weeks. I just want it running again.
Also, did you label which parts go with what, so as not to mix up the components of the various assemblies?

That whole 2 part assembly is the Delivery Valve and the central Valve only goes into one end of the Cylinder and both parts need to be kept together as they are mated together.

cooljjay 06-30-2014 02:35 AM

What brand mounts did you use? Lemforder or Phoenix are the only ones that should be used. Did you do the trans mount?

Have you adjusted the fuel pressure relief valve?

npretnar 07-08-2014 09:23 PM

Quote:

Originally Posted by cooljjay (Post 3351187)
What brand mounts did you use? Lemforder or Phoenix are the only ones that should be used. Did you do the trans mount?

Have you adjusted the fuel pressure relief valve?

I used Lemforder mounts and also replaced the trans mount and engine shocks. That was last summer. It shook at idle for a while, even after a new IP adjustment bolt, but it didn't "idle rough." In other words, the engine sounded fine, didn't smoke, and there were no misses.

What is the fuel pressure relief valve?

cooljjay 07-08-2014 09:27 PM

This thread should explain it

http://www.peachparts.com/shopforum/diesel-discussion/234609-fuel-pressure-relief-valve-adjustment.html

npretnar 07-08-2014 09:31 PM

UPDATE
 
So I removed the IP and set the engine to 24 BTDC (ears on cam lobes pointing up). I then set the tooth on the injection pump to match with the mark, replaced gasket, remounted pump, timed it to one drip per second keeping constant pressure on the plunger (pushing the plunger once every two to three seconds), fastened down all the bolts and reattached all of the injector lines, bled the system, started the car and it ran rough with lots of black smoke. I let it warm up, but still tons of black smoke at idle and even more at WOT. It still shakes.

One thing I noticed ... when turning the bolt on the IP shaft (clockwise of course), I encountered resistance in what I would call the first and third quadrants if you were imagining a graph laid over the shaft of the IP looking at it from the front of the engine. To me, this resistance felt like the type of gravitational resistance that would happen if you were holding a bowed rod out in front of you and trying to turn it. Answer me this gentlemen ... is it possible for the shaft inside the IP to be bent, or bowed?

spock505 07-08-2014 09:49 PM

Have you pop tested the injectors?

npretnar 07-08-2014 10:09 PM

Quote:

Originally Posted by spock505 (Post 3355289)
Have you pop tested the injectors?

The injectors were rebuilt by Greazzer with new nozzles last year. I don't think they're the problem.


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