str8axle55
1/2 ton status
I have a pressure tester you can borrow if you`d like.
CK5
Register an account today to become a member! Once signed in, you'll be able to participate on this site by adding your own topics and posts, as well as connect with other members.
Oh what the head gasket!
- Thread starter Chevy305
- Start date
if you can air hose quick release it, with a gauge, fill it to 15 and disconnect, than let it sit for a 1/2 hr and check.. sure have at it...
or you could not be a cheaparse and just buy the tool...
Go to autozone and borrow their tester set for free. (or borrow one lol)
Ok compression test results are in:
#1. 180
#3. 175
#5. 175
#7. 225 - this cylinder had coolant blowing out of the spark plug hole while testing the other cylinders.
Its obvious that there's a problem with the #7. I just got the new head gasket in the mail so I'm going to start tearing into it tomorrow.
#1. 180
#3. 175
#5. 175
#7. 225 - this cylinder had coolant blowing out of the spark plug hole while testing the other cylinders.
Its obvious that there's a problem with the #7. I just got the new head gasket in the mail so I'm going to start tearing into it tomorrow.
Ok so I cycled the engine a few more times to blow all the coolant out of the #7 and redid the compression test. I got 185psi. So now, what does that mean?
If you have coolant in cylinder I can't see any other recourse but to pull the head.
Never had a cracked head, so no idea if a very small crack could leak coolant but still provide good compression numbers, but it would be something I'd look for anyway.
I'd bet if you pressurized the cooling system, you'd fill that cylinder up.
Never had a cracked head, so no idea if a very small crack could leak coolant but still provide good compression numbers, but it would be something I'd look for anyway.
I'd bet if you pressurized the cooling system, you'd fill that cylinder up.
Until you remove it I don't see how you can know if it's the head or the gasket.
At least you've got it narrowed down to one cylinder so you know exactly where to look.
Never having lost a head gasket, I don't know if you can tell where one has been leaking once you pull the head off or not.
Another thought, did you hit the head bolts up with a torque wrench again, just to check if any were loose?
At least you've got it narrowed down to one cylinder so you know exactly where to look.
Never having lost a head gasket, I don't know if you can tell where one has been leaking once you pull the head off or not.
Another thought, did you hit the head bolts up with a torque wrench again, just to check if any were loose?
Basically just means you got all the coolant out and the compression is OK.
Having coolant in the cylinder caused the compression reading to be higher.
As for a cracked head, hopefully its a gasket, but if not, then better a cracked head than a cracked block.......
Do a leak down test to be sure, I've had an engine with a blown head gasket have fine cylinder pressure, but the leakdown on two adjacent cylinders was 50%!
My guess is you have a head gasket out (or intake, or leaky bolts), it filled the cylinder and sealed it off, with a smaller chamber (because of the extra fluid), and when you drained it the compression went back to norma. That doesn't mean you don't have a small leak though. Hook up 120 psi to that cylinder (with the valves closed) and listen for bubbles in the radiator...
You really should of sealed the bolt threads too, yes.
My guess is you have a head gasket out (or intake, or leaky bolts), it filled the cylinder and sealed it off, with a smaller chamber (because of the extra fluid), and when you drained it the compression went back to norma. That doesn't mean you don't have a small leak though. Hook up 120 psi to that cylinder (with the valves closed) and listen for bubbles in the radiator...
You really should of sealed the bolt threads too, yes.
Well, if the gasket is blown between the coolant port and intake port it can flow through the intake port, through the valve, and into the chamber. If it's #7, it's next to the coolant port, doesn't flow into the intake, but it is there. More than likely it's a head gasket though, I agree.
If the head gasket was leaking you'll be able to see it when you examine the gasket, deck, and head. My leak was very small, but you could still see it. When my dad blew the head gaskets on his 502 blower motor it was obvious where they were leaking too.
Make sure you check the flatness of the head, you may need to have the heads shaved.
I am just saying that is like 3" or so where it would seem it would leak into the oil or out rather than along the gasket. I just hear it as a suggestion alot but it seem unlikely. I would be pulling the head right now before it rusts the cylinder and the antifreeze starts messing up bearing. Be sure to change the oil at least twice once it is fixed.
Yeah, I agree it's not as likely as a head gasket, but the intake is a vacuum and the coolant is under pressure, it is possible for it to suck it in. Of course it's not like the pressure cycles a head gasket has to go through though, not even close. I think were on the same page. Although I don't know why I'm even bothering explaining it, because of the fact that it is not likely thats the problem.
Actually, I'm on Page 2 there...
haven't read the replies, just the comp numbers.. the reason the # was higher the first time was cuz there was fluid in it.. once you evacuated the cylinder, the # goes down...
did it overheat bad at any point? you just put this together a while back right? new cam and stuff? where those aftermarket heads, Patriots or something?
did it overheat bad at any point? you just put this together a while back right? new cam and stuff? where those aftermarket heads, Patriots or something?
