I have recently performed a compression test on my 1972 V4. After a little research and reading that the compression ratio as standard was 9.0 I assumed I should be looking for, no hoping for, as close to 175psi, or at least around 150psi.
The cold engine results:
Cylinder 1 = 95, 2 = 95, 3 = 95, 4 = 90.
With a tiny squirt of oil, 1 = 100, 2 = 100, 3 = 95, 4 = 100.
Hot engine result were almost the same as the cold results. The car pulls quite well, but I’ve never driven a 96V4 before this one. I live in the Shropshire countryside, high up Brown Clee Hill, but the car takes the hills with aplomb.
Back ground issues:
Oil consumption is very minimal. It leaks more than it consumes.
Spark plugs are a decent colour after a decent run.
Engine hasn’t overheated with me, but rad has signs of leaking by the cap and expansion bottle is pretty muddy.
I have yet to check the valve clearances.
Am I looking at worn piston rings/cylinder and or worn valve gear? Any guidance would be most appreciated.
I have just bought a 1976 ’96 and had the head gasket blow. Prior to that I did a compression test and was reading compression very similar to yours, the engine has done 54,000.
My thoughts would be not to worry if it’s not using gallons of water or vast amounts of oil!
Enjoy your motoring.
Thanks John. I have since the test taken this exact advice. I’m busy looking at the structural rust issues in the engine bay floor and cabin floor at the moment and rebuilding the damp and deformed internal trim panels with ply and new foam liners and will, when the clutch needs replacement take the engine apart and rebuild/replace as necessary. I plan to restore once the summer ends.
Good luck with yours. I hear its cheaper to rebuild engines to 1700cc version than the 1500cc. Have you met Graham McDonald in Bromyard. He’s a Saab 96 google like resource.