Brother in Law Broke Down

[bobsquatch]

My Brother in Law just bought his first diesel truck last month, an 86 F250 4X4 XLT with a 4 speed manual and a 6.9. Well tonight I had to go get him because I am pretty sure is his injector pump failed. Truck still runs but is way under powered and oil is leaking from behind the pump and a small amount is boiling out the oil fill cap. There is also a loud tap I could not isolate but it is slow at idle like twice per second. Are the 6.9 and 7.3 pumps interchangeable? This truck has been freshly rebuilt (sans the pump apparently) and has a nice ATS turbo set up on it. Should he replace the stock pump or are there competitively priced better aftermarket pumps out there. I remember when I had my 7.3 IDI that the pumps were good for roughly 100k miles and were expensive like $1000. I think they are much cheaper $2-300 now but am not sure. Should he get it at Dion, Napa or somwhere else? Any advice would be appreciated. Confirmation that it is probably the pump would also be helpful obviously. Thanks

Bob

[TurboYT]

Note sure that the pump is the problem. However if he is going to get a new pump I recommend he talk to Ken at DPS. He can get a rebuild pump (one that's been worked for power) and matching injectors for probably less than $1,000. There is a great 6.9 forum on thedieselstop.com. They should be able to isolate the problem better. You can also get Ken's info from there. His username on thedieselstop.com is landyatch.

[bobsquatch]

Thanks I'll check out the thread. Do you have a specific idea why it may not be the pump? The way I see it is there is not much else to fail in these things without being catastrophic.

[TurboYT]

It could be but I don't know why the pump going would cause oil to bubble up.

[bobsquatch]

OK, I replaced the injector pump today and solved a couple problems. Idle knock went away with oil change and no more fuel leak. Power is also likely restored but but I think the timing is too advanced too run safely. All I need to do to remedy that is loosen the 3 ip mounting bolts and rotate toward drivers side correct? Anyone have a good method of adjusting by ear?? The engine quiets down and idles good when I press in the advance lever on the drivers side of the pump. (thats what that is right?) Now on to the potentially big problem. The trace amount of oil boiling out of the fill cap is still there and I know why. I am getting significant crank case pressure pulsing with the running engine. I know this can be caused by serious problems such as burned rings or a bad valve but is there a possibility that it is minor ie a bad egr valve or something? If so how would I go about testing for that? Thank you in advance for your input.

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02 F350 XLT PSD 4X4 auto CC LB 373L/S SRW DUAL ALT with coveted manual TCASE/HUBS

[bobsquatch]

One other issue... He is running a triple fuel pump setup. The ip is fed by the lift pump which is fed by an electric unit. Could this contribute fo a ip failure or fuel in the oil? It is no big deal to bypass it, just pull the power and it runs without it. Are there any cons to this setup? Any pros?? Thanks again for your input.

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02 F350 XLT PSD 4X4 auto CC LB 373L/S SRW DUAL ALT with coveted manual TCASE/HUBS

[bobsquatch]

Ok I am with the truck right now. The good news is the crank case pressure is constant not rhythmic as if a piston had a hole in it. The bad news is it is excessive. Probably over 1psi. enough to whistle out the rivet in the fill cap when idleing. What could cause this or is it normal

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02 F350 XLT PSD 4X4 auto CC LB 373L/S SRW DUAL ALT with coveted manual TCASE/HUBS

[Godzilla Jr]

Mechanical lift and electric lift together may not be the best idea. I'd stay w/electric and bypass mechanical lift completely.
Too much pressure to the IP inlet is not recommended unless you have free flowing intake and exhaust, EGT'S will be unreal.
To time the pump loosen the 3 screws and turn IP untill "Marks" will align. These are static timing marks on housing and IP flange. Then turn IP to drivers side about .030", thickness of a dime, at a time. This will be about 2* advance for each .030". If motor has turbo then 8* BTDC will be OK. Not sure of timing for non turbo. This will get you real close. Best to have it timed with light and adapter.

If internal crankcase pressure is high, the CDR valve may need replacing, no EGR valve on these beasts. Looks like a "Tuna Can" on its side with a 1" hose attached going back to intake. One part for all 6.9-7.3's. Don't know part number off top of head.

Go over to The Diesel Stop and go the basement forums (6.9). There you'll find PLENTY of help for these older vehicles.

Chriss

[bobsquatch]

Thanks for all your help. The blow by issue was traced down to a grommet in the valve cover that my brother in law replaced that did not have the flapper cut out. A virtual plug between the crank case and intake. Some quick knife work and problem solved. Thank you everyone for all your time and advice. I genuinely appreciate it.

Bob

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02 F350 XLT PSD 4X4 auto CC LB 373L/S SRW DUAL ALT with coveted manual TCASE/HUBS

[bobsquatch]

Thank you Zig and everyone who helped me with all of this. End result is a healthy 6.9 with a new ip that is timed reasonably well, runs great with normal egt's around 875 and no excessive crank pressure or smoke. I disconnected the electric fuel pump since the mechanical lift pump is new and runs fine without it but will leave it in place as a redundant backup. No knocking clicking or tapping which was probably caused by diesel in the oil. Thanks again to everyone who contributed to the successful completion of this project. Perhaps this thread will help people with similar situations in the future.

Bob

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02 F350 XLT PSD 4X4 auto CC LB 373L/S SRW DUAL ALT with coveted manual TCASE/HUBS

Edited by BOBSQUATCH (11/22/04 02:30 AM)

[TurboYT]

Where did you end up buying the pump from? And for how much?