232 valve chatter/oil flow problems

[dptyrob]

I've got a 69 or 70 Scout 800 with the AMC 232 6 cylinder. The best I can tell this vehicle has not seen road use in about 15 years. I had it towed out from the boneyard and began the process of getting it running. Before starting it I pulled all of the plugs and poured 3 ozs of marvel oil in each cylinder. I also drained the oil, poured in about 1 1/2 gallons of kerosene, put in a clean oil filter (filled w kerosene) and pumped the kerosene through the engine with the a drill/oil pump. I let it sit several days and repeated that step several times before draining the kerosene. Then I put in another new filter and new oil, pumped it through the engine/filter with the pump for a few minutes and started it (after rigging up a fuel supply and installing new plug wires, distributor cap, and rotor button).

Wonder of all wonders this thing started fairly easily and it runs pretty smoothly. However, the oil pressure was only getting up to about the 1/4 mark on the gauge (after it was warm) and if you rev the engine up the valves start chattering. After about 2 or 3 15 minute sessions of idling over the course of a couple of weeks, I finally poured about 20 ozs of Marvel oil into the oil. It didn't make an immediate improvement, but the next time I came out to start it, the chatter was almost gone and the oil pressure was running at around 1/2. There is still some chatter, though. So I pulled off the valve cover today and started it up. I observed that almost all of the valve rods rotated as the engine ran, but I saw no oil circulating anywhere. A couple of the valves seemed to have a little oil seeping around them, but no flow to speak of. I'm not quite sure what I should be seeing here, but I was expecting to see some oil gushing or squirting and draining back down throught the head. If so, where should I start on this?

[Jaffer]

You should see a bunch of oil splattering around under the valve cover.
There's a chance the lifters and pushrods have crudded up.
Oil is supposed to flow from a gallery passing across and into a hole in the midsection of the lifters. The lifter then pumps oil up through the pushrods to lube the rockers and valve stems.

You could loosen the rocker arm assemblys then remove and clean out the pushrods ... keeping everything in the in the same order of where they were removed. Pour a little Marvel oil at a time down through the pushrod holes onto the tops of the lifters then use a pushrod to plunge and purge them. The lifters won't plunge much more than 1/8" so don't go smashing on them too hard. Try inserting a push rod, place a piece of wood on top of it and gently tap the wood block to actuate the innards of the lifters.
This may be worth a try as it won't take a lot of disassembly since you already have the valve cover off anyway ...

[dptyrob]

I found an article regarding a recurring problem with oil circulation in 199 and 232 engines of this vintage. One of the head bolts actually runs right through the oil channel going to the rocker arm assembly, and they were notorious for clogging up at that location and causing oil starvation. The fix for this problem (outlined in a TSB) was to either run an external oil line to the rocker arm assembly, or modify the head bolt by grinding it down some at the point where it crosses the oil channel.

Last night I pulled the rocker arm assembly and will be cleaning it thoroughly, as well as the oil passages in the head. The valve rods are solid on this particular model. I think it was 70 or 71 that AMC changed this design to where the oil comes up through the valve rods, according to the article I mentioned. The lifters all feel pretty good and they seem to move freely from what I can feel with the valve rods. There's enough suction in them to where when I pull the valve rods up that they come with it, until they go as far as they can go and break the seal. Then they fall right back in place.