No Compression on 2 and 4

moosemanusa · Post by **moosemanusa** » 03 Mar 2014, 10:57

Hi There,

Buddy of mine picked up a S70 T5 1999 model, it was at a shop where the old owner had given up putting money into it, they claimed it had "thrown a rod" the timing marks were all spot on to the exact tooth, there was spark also, so decided to do a compression test. It was a rented one from oreileys but it gave the following.

Cyl 1 = 40 PSI
Cyl 2 = 0 PSI
Cyl 3 = 60 PSI
Cyl 4 = 0 PSI
Cyl 5 = 40 PSI

I left the guage on and it didnt leak down at all which is odd however I know those numbers are way down (not forgetting I don't know the quality of the test kit)

So decided to pull the head off, everything looks straight, no bent valves and there freely moving before hand.

So My question to the world is:

1 - We are going to have a buddy of a buddy look over the head (head specailist) and see he notices something I cant see.
2 - Could it be pisting rings, I dont see any damage to the cyl walls, there's carbon on the pistons but nothing that looks bad, head gasket did have some water/coolant on the gasket itself, allthough the actual part looks good.

So if it was the gasket it could at least explain the lost of compression..

Any ideas?

Post by **jblackburn** » 03 Mar 2014, 10:59

Probably overheated - I wouldn't be surprised if the head is warped slightly.

Post by **E Showell** » 03 Mar 2014, 11:04

No visibly burned exhaust valves?

moosemanusa · Post by **moosemanusa** » 03 Mar 2014, 11:16

They are very black, along with the top of the pistons, I've never gone this far into an engine before so not sure what to expect.