bigguy75inches

I got a new theory in my head now, here is a pic of what i have in mind,,, i checked 3 cylinders for compressoin,,, i checked number 7, 5, and 4 . numbers 2 and 7 are my problem cylinders at the moment, but,, what if i blew the head gasked inbetween 5 and 7, and 2 and 4? wouldnt any pressure building up be leaking into the cylinder next too it thus causing a low psi reading? that could be why 7 and 5 are roughly the same, and 4 is low because its next to 2. it could be doing the same thing and just leaking into the next cylinder. Any thoughts on that? ill post a pic of what im describing.

Flyer

iTrader: (1)

LOVE that pic! I think it sounds a little far fetched ... how are you doin the compression testing? Did you take all the plugs out? That would prolly make a difference.

bigguy75inches

"LOVE that pic!" that pic is probably what my cylinder walls really look like! haha.

Alright, another idea, my timing chain jumped gear, and is off by one tooth. that would throw the cam shaft on the wront time, therefore causing my valve's to be open and closing at the wrong time. therefore opening too early before top dead center. and thus loosing compression.. that too would explain why im getting 80 all around.

bigguy75inches

Every mechanic ive talked too never said anything about pulling ALL the plugs just to test compression. I dont see how it could make a difference. As far as testing, i use 2 different testers, one that you just push up against the plug hole and hold it, and a better screw in type. they both got the same reading.

bigguy75inches

well,, i checked number 6 just a sec ago, and guess what 120 psi! im fixing to go and check the remaining cylinders.. looks like my blown head gasket theory might be the ticket.

Flyer

iTrader: (1)

Have you ever overheated it? I know that would make the head gaskets blow, but if that's the case, you should check the heads out when you get them off to make sure they aren't warped.

bigguy75inches

no,, ive never overheated it before,, i overheated my first truck,(1962 gmc) and ever since i watch those gauges real close.