Hello everyone,

If an engine has not been started for ten years, will it show low compression numbers before it has actually been started? Should the engine actually run for a little bit and then have it checked for compression? Please help! Today was the day I was going to get the car running after 2 years and I got the bad news from my mechanic that it might be a tired engine. The trustworthy person whom I bought the engine from, a Classiczars.com member, told me that he had the head rebuilt about 5k miles before it was removed to put in his V8. I'm just praying that my mechanic might be making a mistake.

Thanks everyone.

Saro

If the engine hasn't be run in a couple of years, it may be a good idea to change the oil/filter and also remove the plugs and squirt a small bit of 30w into each cylinder before cranking it over. If you've taken a compression test on an engine thats been sitting that long, its likely to show lower compression than it would if it was a daily runner. New plugs, point/condenser (if you have them), rotor/rotor cap, and maybe even plug wires are always a good think as well.

Thanks 240zx.

I called Rebello to ask them their advise on this, and they said that its a waste of time getting a compression reading without running the engine for at least 30 min. So Im going to check with my mechanic to see if that is the case.

Thanks again,

Saro

10 years is a long time, may be stuck rings, stuck valves, may be worn out.... I'd get it running and check the compression hot, or get it running for a while then do a leak down check which is much better at telling you what is wrong. It just may be that the valves are rusty and not sealing well, a short run will clean them up and maybe improve things.

Thanks for all the help.

From research I have found out that proper way to check compression would be to put all new fluids, have the engine warmed up, have the throttle full opened and then check for compression. Without any of this done and the engine sitting for ten years with only one cylinder tested it gave a 75psi reading. I'm hoping maybe with new fluids, warmed up engine, and the throttle opened, it should add up to a normal reading

Anyone else?

This could happen , but oil the cylinders first and spin the engine with the plugs out . then start it.