rattle or knock on right side ?

[KEVIN MUNCASTER]

I went to look at a 92 6.2 in the dark and rain last nite (first mistake). It starts right up (32 degrees outside) which was a plus. It idles nice, not too smoky, very smooth, but has a strange rattle coming from the right side (passenger) Could be the fuel pump or the non functioning AC compressor. (Hopeful) or could be internal. What should I look for ? Truck is a 5 speed 2wd, 189,000 miles, rough condition but price is right if the driveline is okay.

Owner says timing chain and gears original, has been run with a leaky rad. Maybe overheated at some point. I checked for pressure at the oil filler and rad cap for air bubbles, looks okay.

opinions ?

Kev :confused:

[NH2112]

The first thing I'd do is run it to get the engine up to operating temperature, then listen to it. Driving it would be better because you'd be able to see if it varies with engine speed. After that, loosen each fuel line (at the injector) one at a time and listen to see if the sound goes away or changes. 189K isn't very many miles at all when it comes to a 6.2L, assuming everything's in decent shape you should easily make it to 300K. Perhaps the seller will let you put a quart of ATF or Marvel Mystery Oil into the oil and run it to see if it loosens anything up to stop the noise, or mist water into the intake with the engine at around 12-1500RPM to help loosen up any carbon deposits that may be raising the compression ratio slightly.