Knocking 1989 7.3 idi. Help!

[Beefguy]

I have a 1989 7.3 with 189k on it. It was starting hard so I replaced all glow plugs and that solved the hard start. It has a knock to it that I'm not sure which direction to go.. the oil pressure gauge reads low. Doesn't smoke, power seems good, and doesn't use oil or antifreeze. The gauges are questionable at best rpm doesn't work voltage is low with new batteries and oil pressure is very low. Injectors? Lifters? Thanks!

 

[BrianX128]

How do you know the oil pressure is low and what is it at? If your going off of the factory gauge it's almost totally useless.

 

[Beefguy]

Yes factory gauge.

 

[Macrobb]

The factory gauge will read "nothing" or "something". Anything above dead low is "something" which means at least 5? 10? PSI.
That's because the gauge is just reading off a pressure switch... Any variation in the gauge is simply due to voltage fluctuation by the alternator as it warms up.

Also, a "knock". When do you hear it? Idle? off idle? under heavy load?
Does it go away at any time - does it get better or worse when cold?

 

[Beefguy]

The knock never goes away and is the same no matter the temp or rpm. I just had high pressure oil pump replaced because it was letting oil into the antifreeze. Which seemed to make oil pressure gauge read less. Gauge is irrelevant but still weird.

 

[BrianX128]

The what? Lol..

 

[Beefguy]

Oil coolerSorry

 

[icanfixall]

Welcome to the forum. What are you calling the high pressure oil pump? Is it the pump on top of the engine center or the oil pump in the oil pan under the engine? With this many miles on the engine you may need a set of injectors. Please do not buy from the cheapest ebay seller before asking this forum for the best parts money can buy.Sadly owners come here AFTER they purchased cheap crap. Get no warranty and royal screwed over by horrible ebay business jerks.

 

[Beefguy]

Oil cooler.. . Which injectors would you recommend?

 

[IDIoit]

call up CDI conestogadiesel.com or R&D idiperformance.com for injectors,
I believe typ4 has a set, don't know if he sold his last set or not

 

[Macrobb]

Yeah, chances are injector. That's pretty much the #2 issue with these trucks(#1 being timing, especially after replacing injectors or IP)

 

[Beefguy]

Would you recommend replacing the injection pump at the same time?

 

[Hydro-idi]

Would you recommend replacing the injection pump at the same time?

Yes. Sometimes fresh injectors will cause an old IP to struggle with making enough pressure for injectors to pop fuel into cylinders. It's always best to replace both units if funds allow. You will see the greatest benefit by doing so.

 

[icanfixall]

The best people to buy injectors or injection pumps from has been listed. Yes... Replacing both pump and injectors at the same time works the best. You will need to time the engine for best hp and mileage after doing this work. DO NOT LET SOME SHOP TIME IT BY LISTENING TO THE ENGINE RUN... Thats foolish and it wont work.

 

[Beefguy]

Thanks for your info and help!