hmmmm....How sure are you on that?

The Isuzu Owners Manual for my 1998 Amigo says the lifters need adjusting every 60,000 miles

There is a sticker on the hood with vacuum line diagrams and hot and cold valve clearance tolerances.

My 1998 Amigo/Rodeo Helm manual lists tolerances and adjusting/shimming procedures for the 1998 DOHC 3.2L V6.

The dealers had no problem looking up parts and labor for the task. I called them and asked them how much it cost to have it done.

I find it odd that all of these vehicle and year specific sources seem to indicate that the valve lash indeed does need to be and can be adjusted.

the 2.2L 4cyl DOES use hydraulic lifters however.

FWIW I have tried the racing the engine technique with no luck. I've been driving like normal as well.

Mike

My wife's Mazda Millenia did this same thing at 34,000 miles, the engine had a stuck lifter. I drained some oil out, added a quart of engine flush and ran it about ten minutes, did an oil change and added some Marvel's Mystery Oil, and ran it for a few hundred miles. I changed the oil again, and the noise seems to have gone away.

i'm gonna leave this to some one who actualy knows the DOHC engines (unless i'm gonna get a go ahead on fixing the one that is knocking in my shop).

I wouldn't trust the dealer too much. They are more than glad to take your money & do absolutley nothing (i deal with many of them every day).

Again i'll let some one with more experience with these engines chime in.

The Isuzu 3.2/3.5 liter engines have mechanical lifters. They are adjusted by replacing solid disc shims that are captive by the guide that goes into a polished port in the head that the valve springs valves fit in. I doubt very seriously that a shim or guide has come off or apart since they are both pretty substantial pieces of solid machined steel.


As a side note, I have found the easiest way to adjust the valves is to take measurements of the lash gap and pull the cams to replace shims, IF NEEDED. Once you have pulled the cams from the head and can identify the alignment marks, it is no big deal. Since they are gear driven and not directly connected to the timing belt, it takes about 15 minutes to pull both cams on one side and put them back on. Takes ten times longer to pry all the lifter shims from the valve stem cups, than to pull and replace the two cams.

All right, bring this one back (I was out of town for work last week). Despite my best efforts to find something else wrong, it appears I have the wonderful rod knock.

Valves were mostly on the loose side of spec, ie, at the maximum gap, except the exhaust valves on a cylinder on the passenger side which was a couple hundreths over (~.02)

Several opinions from fairly knowledgeable people all said rod knock.

So now I am in the process of pulling the engine.

Mike W