No Compression in # 2
- Thread starter KDBL1TY
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WyoSyclone
Active member
Re: No Compression in # 2
Might pull the valve covers off and see if you have a broken valve spring, or retainer problem
Might pull the valve covers off and see if you have a broken valve spring, or retainer problem
WyoSyclone
Active member
Re: No Compression in # 2
Well, if you had a broken spring it would be obvious - that valve would be sitting low. Sounds like the valve spring retainer is OK too... sounds like you're just going to be pulling the head off - really no other option...
Well, if you had a broken spring it would be obvious - that valve would be sitting low. Sounds like the valve spring retainer is OK too... sounds like you're just going to be pulling the head off - really no other option...
WyoSyclone
Active member
Re: No Compression in # 2
Well, regardless of what a leak-down or compression test tells you, I think you're kind of stuck with not having any compression in that cylinder.... removing the head will tell you what you're up against
Well, regardless of what a leak-down or compression test tells you, I think you're kind of stuck with not having any compression in that cylinder.... removing the head will tell you what you're up against
blk00z28
Forced to by choice
Re: No Compression in # 2
Broken ring land would still support some pressure in the cylinder for a short period of time. It would just read low until it leaked out.
If its zero, then its a hole in the piston, a hole in a valve, a valve is hanging open. There isn't to much more..
I'd just pull the motor anyway.
Broken ring land would still support some pressure in the cylinder for a short period of time. It would just read low until it leaked out.
If its zero, then its a hole in the piston, a hole in a valve, a valve is hanging open. There isn't to much more..
I'd just pull the motor anyway.
blk00z28
Forced to by choice
Re: No Compression in # 2
If you take the valve covers off again, take a rubber hammer and pop the springs for that cylinder. Don't tap them to hard, but enough to push the spring down and open the valves. Retest the compression. You will hear it leaking around the valve if its a head problem. If you hear nothing and it still has no compression pull the head at least.
Believe me, get right to it that way you know what you need to replace and you might be able to do it fast.
If you take the valve covers off again, take a rubber hammer and pop the springs for that cylinder. Don't tap them to hard, but enough to push the spring down and open the valves. Retest the compression. You will hear it leaking around the valve if its a head problem. If you hear nothing and it still has no compression pull the head at least.
Believe me, get right to it that way you know what you need to replace and you might be able to do it fast.
Re: No Compression in # 2
Try what the previous post said first. If you do a leak down, a valve problem will let air up to the tb and to the exhaust if it happens to be a problem with the intake and exhaust valves respectively. If it is a hole in the piston, the air will go directly to the lower end and then come out up top (into valve cover) so you'll hear the air escaping there. As mentioned, a broken ring would hold some compression. I can assume that you are at WOT when doing the compression test since the other 5 are all on the same level with each other. Absolute zero in a cylinder - I would plan for the worst and say it is a piston. Even if the exhaust valve was hung open to the point that all air immediately escapes, I would assume that the piston would hit that valve and stop in its rotation.
Try what the previous post said first. If you do a leak down, a valve problem will let air up to the tb and to the exhaust if it happens to be a problem with the intake and exhaust valves respectively. If it is a hole in the piston, the air will go directly to the lower end and then come out up top (into valve cover) so you'll hear the air escaping there. As mentioned, a broken ring would hold some compression. I can assume that you are at WOT when doing the compression test since the other 5 are all on the same level with each other. Absolute zero in a cylinder - I would plan for the worst and say it is a piston. Even if the exhaust valve was hung open to the point that all air immediately escapes, I would assume that the piston would hit that valve and stop in its rotation.
pinellas50
New Guy
Re: No Compression in # 2
I have had zero compression in a cylinder before. It ended up that BOTH of the rocker studs pulled out of the head so neither valve was opening.
I have had zero compression in a cylinder before. It ended up that BOTH of the rocker studs pulled out of the head so neither valve was opening.
