Engine/Transmission (1994 - 1998) Is this right?

[CSimpson]

shop in southern, IN

Jim Jessup is in Vernon, IN, he was head engineer that designed the 12V and also wrote all the service manuals, when you see a pair of hands in the manual they are probably his... you can reach him at (812)873-7618, and he usually takes Friday off, works Saturdays... . he is a great guy and will help you anyway he can, and will stand behind his work 100%. He is a pump timing specialist. Good luck.



Clayton P. Simpson

 

[tp0d]

matthug I replaced the line with some fuel hose and there was no difference, then I unhooked it and there was no difference. I still need to find the metal line. Cummins is not helpful down here at all, they wouldnt order me the metal one because my serial number didnt come with one.

If the rubber line didnt blow off with a good bit of boost pressure, its possible your AFC bellows is blown. I dunno if that happens much at all, I`ve never read about it. .



Best way to test that would be to remove the AFC entirely, and hook it up to shop air, regulate 10-20psi into it, and see if it moves, or just spews air. . Might be the problem. .





good luck



-j

 

[Matthug]

I agree, probably a ruptured diaphram in the AFC housing.

 

[TGroves]

well, akron could not find any boxes for the injectors ,,, i have read lots on this form but thats the first time of hearing about using air to move the afc,,, a friend told me that my "aneroids" in the afc housing may be bad? hope i spelled that "aneroids" right

 

[Joe G.]

Testing to see if it is the AFC is really easy. Take the whole AFC off. Cover the hole with something to keep dirt out and oil in. Go for a test ride. If it smokes like crazy and hauls butt the problem is the AFC. If no change then something else is wrong.

 

[AKron]

Ok I got the line back on and it runs the same. What all do I need to remove to test the afc?

 

[Joe G.]

There are four hold down screws for the AFC. One of them is the "tamper proof screw" that can be a PITA to remove to replace the plate. That all four of them out. Lift the whole AFC off the top of the back of the pump. Tie up so it won't flop around. Cover the hole. Go for a ride. If the AFC was the problem, the ride will have a lot of power and smoke a lot. The reason for that is that the AFC foot (throttle stop) is not in the way of the governor follower so it will go against the plate profile regardless of boost.



Sorry about being a little slow to respond. I'm not at home so I'm using another computer when I can.

 

[AKron]

What if I just removed the afc arm?

 

[Matthug]

You can do that too if you can't find anything to cover the hole with. You will have tons of smoke though, hopefully the cops aren't sticklers like they are around here for stuff like that.

There's a bolt on the front of the AFC housing, take that out. Then pry on the tab and the rail that the AFC arm rides on should come out. It will have some resistance because there's an O-ring sealing it in. One the rail is out the AFC arm with plop off of it, re-install the rail to seal the housing back up so no dirt gets in your injection pump.

 

[AKron]

ok I took the afc off and hooked it up to my shop air and it moved, put it back on and no change. Next I removed the arm in the afc and put it back, and still no change. It runs the exact same as before the injectors so im kinda thinking I have the wrong injectors again. Does anyone know where I can look up the part numbers? The tips are 7597. I havent called city diesel yet because I want to make sure I check everything before I question their parts. Is there anything I could have missed?

 

[SEmerson]

With no plate any injectors will smoke heavy. It is not the injectors. My guess is the rack is stuck somehow.

 

[AKron]

I took out the arm and the plate was removed before. Is the Afc still used? Does the rack still need to move?

 

[SEmerson]

The plate and the afc are rack limiters. (they really should be in there to properly tune) But never the less without them the rack will slide full farward. If the rack is not sliding you will have very little fuel. You smoke should be so hard to control with your right foot most people would not want to drive your truck. And this is still with stock injectors.

 

[Matthug]

Well I've read using no plate can damage your pump, I guess we have a case in point here.

 

[TGroves]

akron ,,, . . all my problems are the same as yours ,rember in an earlyer post ... had a friend from tdi in indiana here look at the truck and he found that my over flow valve was bad ( the old style) and the new injectors i got from city diesel was not flowing the amount of fuel it was suppose to . . so he pulled the injectors and flow tested them and the pump and balanced them "damm the injectors were 100- 120 psi off " from flowing what 370's are suppose to do (and thats what i ordered)... but now the truck has alot of power and now will burn the tires . . so i hope this helps I have been banging my head on this for three months ,,,, oh by the way i bought the injectors on 4-13-06 "may be a bad set ''''?????????????????????

 

[AKron]

I talked to city diesel today and they said it was a bad aneroid. Isnt that what someone told you too? I am about to take it to a shop and see whats wrong. Was the over flow valve something easy to do or do I need to have someone do it? Thanks for all your help and hopefully Ill have it fixed this weekend.

 

[Matthug]

Overflow valve anybody can do, it just requires a 3/4'' wrench and takes 5 minutes to change. It's on the top of the injection pump, on the engine side, and all the way toward the front of the truck.

 

[SEmerson]

a bad overflow will give you low fuel pressure. Do you have low pressure? It should also cuase cutting out at heavy loads.

 

[TGroves]

was the same words i was told from city diesel ,,,(go figure)?????????????????

 

[AKron]

T Groves, I cant find the box but Im pretty sure I bought mine in April too. Do you think I should have my injectors tested? About how much would an overflow valve cost and where could I get one?