32 6cyl compression pressure

[Dick Kemper]

On my 32 Rockne, I finally got to checking the compression.

Measures 55 to 67 PSI with an engine that has been running but has been idle for about a month.

Someone told me to add a little oil to each cyl. and check again, what should I expect if I did that?

Is the 55 to 67 spread ok? Is 55 lower than can be expected?

Dick

[dictator27]

If you squirt oil in the cylinders and a retest shows an increase in compression, that indicates weak, or stuck piston rings, possibly excessive cylinder bore wear. No increase in readings would indicate possible valve problems.

Did you have the throttle fully open while doing the test?

The compression gauge should be registering maximum obtainable pressure after about six engine rotations.

A spread of 10 pounds between cylinders is acceptable. This is a low compression engine, so variations would be less noticeable. What were the readings?

Terry

[Dick Kemper]

With a little oil added I get: 65,70,80,75,70,75. Looks like adding the oil gives about 10 lb. more than dry.

What should I expect from this engine, I just had it re-ringed?

Dick

[dictator27]

Some questions, Dick.

The new rings are on the original pistons?

Were they standard size rings?

Was there much cylinder bore wear?

Were the pistons checked for clearance in the cylinders?

Was a glaze buster run through the cylinders?

Were the valves ground at the same time?

How many miles on the engine since the work was done?

Just trying to get a feel for things, not questioning whoever did the job.

Terry