Triumph Repair: dry and wet test, valve seals, test jim

Question
Jim, 1974 spitfire IV..I have just done a dry and wet test on my engine. Dry I got readings of 135 on three cylinders except for one I got 120. Then the wet test I got 150 on same three cylinders except for the one I got 135. The spark plugs look ok light brown tan except for the one looks oily, and I can see oil in the spark plug hole when plug is removed. Is this telling me that I need to rebuild the engine or a valve Job valve seals? If I continue to drive the car and I going to cause any further damage? The car runs ok uses oil and does puff smoke sometimes, and can be hard to restart after drive for 20 minutes or more. When is does start I see the smoke when it starts. Stays running get me from point A to B. Could you let me know? What you think?

Answer
Bruce,

I'm guessing that it was the same cylinder with lower readings both times?

There are no valve seals.  Not from the factory.

First step would be to check the valve clearances.   That can be one source of difference in the readings.  And you were consistent between the wet and dry tests, which puts more emphasis on the valve seating vs the rings.

The difference in readings isn't too great, so the question is whether you can afford to take the car off the road for a head rebuild, or whether you'd need to wait until the problem becomes worse.

In the mean time, I presume you're running 20W50 weight oil?


Cheers,

Jim