Hello Gents.

Was wondering if anyone there may be able to help with my 57 problem.

Engine rebuilt - New rod bearing, main bearings, rings, mild street camshaft, new hydraulic lifters, valve springs, valve guides, couple of suspect exhaust valves replaced, rockers, push rods. Oil ways cleaned out. Heads tested and cleaned out.

Oil pump checked and was advised ok as only on 45k miles. 20w 50 oil 40psi on tick over rising to 45-50 general driving.

Seem to be lack of oil reaching the rockers. Mechanics have spun the engine without the heads on and there is some oil is coming up through the engine block. They have checked to see there's no restrictions between block, head gasket and heads and all seems fine.

Rocker shafts cleaned out but still there was very little oil reaching top of the engine. This was a problem previous to the engine rebuild.

Please can anyone supply some helpful information about the oiling system on these 57 371 engines, do they run on low oil in the rockers in general, is there any adjustments such as drilling the rocker shaft block oil way hole etc. We're seriously miffed with this one and would like to resolve the problem.

Many thanks.

Dave B.

 

Back in the day after-market top oiler/lubricator kits were popular. I still see some for sale on eBay and the AACA Forum web site. You may want to consider adding one?

 

I think there is a right and wrong for the rocker shafts...I have not worked on one myself, but have heard that the shafts have a forward end and rear end and/or there is a difference between the left shaft and the right shaft and this has to do with proper oiling!

 

There is no difference in the left and right shaft. When assembling the rocker assemblies be sure the holes (there are two for each rocker) face down (don't ask me how I know). There is one of rocker arm supports (should be the second one from the front on the left side and the second one from the back on the right side) that has a dowel pin in them that goes into the shaft to keep it from turning. These are also the stands the oil comes through the bottom of and and into the shaft. If this is not lined up correctly, oil will not get into the shaft and to the rockers. Even when it is put together correctly it is not the best system ever.

 

Many thanks for your information Gents.

I'll pass your comments to the mechanics involved.

When we suss this, I'll post the answers to help others.

Dave B.

 

The rockers on my '55 were starved for oil. It "turned out" that the surfaces between the rockers and shafts had "polished" themselves together so well that little or no oil would flow to provide lubrication. I turned the shafts (alone) and cut shallow circumferential grooves which intersected with the original oil holes. This restored oil flow. This was done many years ago, and so far, it is still working well.

 

That's the part I had heard about!

 

Hello again Gents.

Bad news, have opened up the engine, now have scored crank (new bearings were installed and its only done 120 miles). Sump full of swarf. We suspect the oil pump. Original engine builder made the mistake of saying the original oil pump was ok, even though I purchased a rebuild kit but it had a different fitting. Instead of waiting for exchange to arrive he went ahead with the build on the old (approx 42k miles) pump.

Engine gets full pressure steam out clean.

I'm on pins waiting to hear if it's a crank grind or hopefully a polish out.

Will keep you updated.

Cheers.

 

Dave, also do a double check to make sure all the plugs were reinstalled as the engine was put back together. The older engines had one or two that are not found on the newer engines.

 

Fortunately the plugs were not removed, the engine has been double checked by new mechanic and plugs are still there.

There may be a problem with worn cam bearings, machine shop is checking all tolerances within the block. Have been advised the engine may not have done the original 41k when sold to me, answers are starting to come in now.

Cheers.