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Discussion Starter #1 (Edited)
i have a 94 f-350 that is knocking. As you step on the accelerator the knock gets louder. Sometimes the knock goes away too. Also after driving constantly for about 30 min it is a real chore to start the motor again after you shut it off. what might be causing this?
 

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Does it have the injection pump with factory turbo, or was it mid year with the electronic injection????? Two totaly different animals! Diagnostics go either way from the differences. If it has the old injection pump then check the gear to see if it is tight/intact. If it is electronic check the valve cover harnesses for melting/fraying. Easiest 2 till it is described what engine managment system is in it. I've seen 3 different engines systems in 94 models that make it hard to diagnose without physicly looking around the engine bay. The one and only year ford was really confusing with diesels.
 

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Discussion Starter #3
it does have the factory injection pump and i believe it came from the factory with the turbo it is a banks?? I do not believe it is electronic and it is def not a powerstroke.
 

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Sounds to me like the injection pump is off time. Heat amplifies the preinjection warm restarts, and is preinjecting before TDC. When it's cold it has to wait till TDC before the fuel will burn hence the easier cool start. The knocking is from the fuel burning quite a ways before TDC and sending a shockwave through the rods/crank/wristpins. I wouldn't drive it till it's fixed because I've seen a couple engine's tanked from this problem and the stress it creates!
 

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Discussion Starter #5
how would I go about fixing this problem is a quick adjustment or something a lot more extensive?
 

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Last time I had to do a timing chain, it was only an idi though, not the turbo idi, so I don't know if the turbo model has a wide range adjuster on the timing gear/pump housing or not. The one I had to do the chain on had 470k miles on it and was always delvac reoiled at 3k. Figured it might be rod knock till I used a stethescope and found no real bottom end knocking. Went into the case cover and saw a floppy dog chain. Tried adjusting the case with no avail and did the chain. After, it ran like new with no knock. Heard from an old mechanic to test this issue, take an injector line loose and crank the engine over with some pressure on the tip of the injector making sure not to release the pressure on the end of thr injector line, then figure out when the piston it is tdc with the injector removed and a coat hanger in the hole. Rotate the crank with a impact gun, have a person feeing for injection pressure and watching the coat hanger piece. If they seem off sink (you want a couple degrese before tdc) then it's the timing chain. I know.....redneckish but they never made a decent tool to do what a couple guys with a little sence could do...... and why pay stupid labor rates to tear and engine down when unneccisary.
 

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Discussion Starter #7
I was talking with a friend of mine who is a mechanic and we got on his ALLDATA program and according to that my model doesn't have a chain it is all gear to gear. Is it possible to just adjust the timing on the pump a little by turning the IP?
 

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You are right, as I looked back at the pics it is a gear assy that I repalaced. Also found a rebuilt injection pump cheap and put that on at the same time. It solved the problem, so it could have been either one. Figured after 470k the pump was in need of service as well. Don't forget to replace all the seals and gaskets while you are in there. I am working some crazy hrs, if I can I'll get the parts sheet from the repair pulled up and get ya all the part #'s and expected labor times.
 

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I keep having nightmares of the 460 gasser and leaking tming cover gaskets!! Might as well do chain since your that deep...... 4hr job that is a PITA and should never have been designd that way. Seems like once a week another pops up for me. Dang uhaul customers, stop overheating our trucks!!!!!
 

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Discussion Starter #10
Do you think the timing gears could be worn that bad with only 160K on the truck? I was thinking maybe it was a bad injector or something.
 

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Discussion Starter #12
Knowing the mileage what would be your next suggestion as to what is making it knock I also was told it could be a chipped lobe on the camshaft???
 

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If it was a chipped lobe on the camshift usualy would be poppiing/backfiring, not knocking. Try cracking injector lines open 1 at a time as it is running to see if can be pinpointed to certain injectors. BE CAREFUL the line pressure is very high and can toss diesel pretty far. Make sure to wear eye protection and gloves. If you find multiple injectors replace them and go from there. If you only find 1 that is making the knock, open the line quite a ways and put a bottle in the valley to collect the fuel and put here under load, if you got no knock. Replace only that 1.
 
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