I have read a lot here about having the IP rebuilt, and was wondering what are the early signs (if any) of the IP starting to go bad? I have 175,000mi on my truck and am almost certain that the injector pump is original, but it still runs great and starts right up. Since it is one of the major repairs that most people claim you will have to do at some point in time, I thought it would be better to be informed before there is a problem.
1983 F350 6.9idi 4x4 4sp

 

If it ain't broke, don't fix it!!
Usualy they will leak from the weep hole or slow you down before they go completely.
If original, that is great mileage from one.

 

leave original pump as it is...when you start having trouble , it could be fuel liines,injectors or any other malfunction.

 

REv the engine to max rpm wiht no load. Watch the exhaust. If it starts smoking and the engine starts to sound like its breaking up it is time for a rebuild.

 

I do not recommend revving the engine to max rpm with no load. The engine was not designed to run at high rpms with no load. The first thing you need to know is what fails inside the injection pump. A big killer in the ford 7.3L is the advance piston on the bottom of the pump. This is a steal piston that rides in the aluminum housing. Over time the piston and more so the housing, wear out and allow too much fuel to leak into the return. This and a warn transfer pump inside the injection pump causes the engine to be out of time. The DB2 series of injection pump by nature will advance the timing as rpm increases. So they use this piston to retard the timing to spec. So a good way to test your pump is to use a long screw driver and push on the bottom of the verticle lever on the driver side of the injection pump. while the engine is idling. If the advance piston is working your truck will start to shake and smoke white because it is retarding the time. If nothing happens when you push on the lever then your pump is getting weak. At work I use a timing light to measure the exact amount of degrees the engine is retarded when I push the lever in. When this piston wears to the extreme, your truck my start to smoke and it may become hard starting after you park it for 30minutes or so.

 

Actually it is the flex ring in the pump get s brittle and falls apart. The linkage on the side of the pump is the mechanical light load advance and does need to be checked with a timing light. There is absolutley nothing wrong with running a diesel to its maxed governed speed, loaded or unloaded. IT will run that speed all day long, so running it at that speed to perform a quick visual and audible test of the engine/pump will not hurt it in the least bit. It is a test that International use to tell you to do.

 

This is very interesting... I have an 88 F250 that has 250K miles on it, and I'm 99% sure that it has the original Injection Pump in it. It has been very hard to start for the last year or so, and we initially thought it was glow plugs. Once replaced, it did the same thing. So, eventually we determined that if we left it plugged in (the block heater that is), it started fine. If it isn't plugged in, its almost impossible to start.

Does that sound like its time for an IP replacement? Any suggestions where to get one of these for a good price, and how much is a good price?

Thanks,
Dean