Im trying to assess the condition of my engine without removing the head.

The car was driven into a Michigan garage in 1982 with 56K on the clock and not driven much since.

Are these boroscope pics what you would expect for 56K or has block been remachined?

What do you make of the brown splodges on cylinder wall?

Finally can anyone tell me what compression test pressure expected on US spec 7.8:1 engine? (Im getting around 105psi)

thanks

David

 

Did not see any of your pictures if posted but..My engine was seized when I go it .. Not an expert but when I tore it down light splotches was ONE of the conditions I found in the cylinders. This is no doubt from lack of proper lubrication such as fogging oil injected into the cylinders for protection prior to storing the engine. Boat owners know to do this every year they winterize a boat. Car owners just park em and forget about them so after 30 -40 years in storage the annual cycle of condensation due to temperature changes inside the cylinders creates H20 and rust. . If your engine turns pretty much pretty sure the brown splotches are light surface rust starting so you may have caught it before more serious rust damage/engine seizure. Honing marks will be radial around the bore but if you have vertical marks they may be from lack of lubrication and or rust forming on the rings. I'm also in MI . Hope you have good luck with your engine.

 

David did you mean a 9 to 1 engine?

 

Oh...somehow missed off this pic!

The car is a US import and has low compression of 7.8:1

 

Most definitely those are honing marks. Given the engine has 56k and has been sitting for 40 years, especially if not in a heated garage, it is mostly the cylinders have been machined. The light brown is the starting of light rust from condensation. You might want to fogg or inject some light oil into the cylinders and rotate the engine to get full coverage to protect it from further rust if your going to keep it in storage especially again if the environment is not heated.

 

If that engine is getting 105 psi (Dry I assume?) then your in good shape! If you have the shop manual you should be able to see what Jaguar recommends?
Now for completeness I would add a bit of oil to each cylinder and run the compression test again but I would be VERY satisfied with 105 psi on that old of an engine.
Especially if the readings are all even and the variation between cylinders is no more that 10% between the highest and lowest cylinder.
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