Well today I just noticed a weird noise. It sounds like someone tapping very lightly on the bottom of a plastic 5 gallon bucket. All of the gauges read fine and about 27psi oil at idle. What could this be. It is driving me nuts. Thanks for the help

 

Also it only has 80,000.

 

Yeah, I chased a knock in mine for about a year. Couldn't ever find anything, I eventually gave up. Looked at almost everything, pulled oil analysis, had the head off and rebuild, injectors, pump, etc... Oh well, never got any worse.

How bad is it?

 

I can only hear it at idle. It seems to have a bit more haze under light throttle but thats the only thing diffrent. Could this be a fuel problem

 

Mine has this also....It seems that when I run Power Service in my fuel, the knock is basically gone.

 

I was just out there and I think I have narrowed it down. It sounds like it is coming throught the intake like it is trying to suck more air than can get in. Is that normal. I think maybe with the colder weather that might have something to do with it

 

It might just be the VP/Injectors you hear knocking away. Might have something to do with running #1 instead of #2, hmm.

 

You may want to try to manually cut injector nozzles out one at a time by cracking the fuel line nut going into the head while the engine is running. If you have a failed nozzle (everyone else here calls them injectors, but technically they are nozzles) you may be able to isolate it buy cutting them out one at a time to see if the noise changes. If one of them is dumping fuel at idle you may hear that change in pitch when you cut that one out. A fuel knock can sound like a mechanical problem.