1982 6.2l diesel

[lmocibob]

my 6.2 started making tick/knock sounds from the right bank valve cover area, i loosend all injector lines to see if noise would go away.
it did not,i used a stethascope to listen for unusaul noise. only abnormal sound is coming from the right side, sound like inside valve cover.
i use hi quality motor oil mobil 1 synthetic
15w-50 plus extra detergent additives.

has anybody had any similar trouble, &what do you think the problem is?

[More Power]

My 6.2 experienced a collapsed lifter once. The sound produced was typical for way excessive valve lash, and seemed most prominent at about 1500-2000 rpm. Sightly less sound produced when cold.

You may need to remove the valve cover to look for a valve train problem. Look for loose/worn rockers, excessive pushrod clearance, broken valve springs, etc. If the problem isn't apparent, you may need to reinstall the injector fuel lines, then idle the engine to check for valve train issues.

Good luck,

MP

[john8662]

MP,

on your collapsed lifter problem you experienced on your 82 model 6.2, was the collapsed lifter visually detectable? I remember reading about you having your entire engine rebuilt to find that the cause of your noise was a collapsed lifter.

Also, what is considered "excessive" for pushrod clearance?

[ZZ]

I had this problem once on an '83 GMC van with the 6.2L. It pecked for me and 2 previous owners. It seemed that the end of one of the valves wore down to the point where the valve keeper jumped off and the valve fell down on the piston at a red light. It sounded like a shotgun went off. It limped for about a mile home. I shut it off and it never started again. It had oil in the water and visa versa.

The reason I think this is that I had a 307 gas burner that did the same thing.

[Chad 2001]

I had the tubing that the rocker arm is fastened to crack at one of the bolt holes and seperate which let the rocker arm move out of line with the pushrod and valve stem. The tubing in question was for cylinders 6 and 8 at the rear of the right side. Inspection under the valve cover will show whether this is the problem. If this is the problem it is a rather easy fix. This was on the original engine for my 1982.

[britannic]

I had a couple of lifters give up the ghost and replaced them without removing the heads (lifter replacement). However, shortly after, the rest started packing up, so I ended up replacing them all - YMMV.

[dieselbegreat]

Chad 2001:
I had the same problem with mine - cracked rocker shaft at the bolt hole on #8. Was backfiring into the intake. Turns out almost half of my pushrods were bent too, on both sides of the motor. I suggest pulling off both valve covers and checking for proper appearance and function because the noise seemed to be coming from the opposite side! And when you torque down the rocker shafts, do it carefully and evenly so you don't stress the shaft. Motor runs great now.