Compression test question - Reliability

[Baileyman]

I recently took off the exhaust pipes in order to replace the oil pan.  I had quite the difficult time getting them back on (it was only myself working on it).  I thought I had them on properly, but noticed that the headers are not all the way seated to the exhaust ports (as observed by the smoke from burning oil that was coming out of them).  I'm going to be doing some top end work soon, and want to assess the cylinder rings by doing a compression test.  Additionally, being the newb that I am, I broke one of the bolts that bolt the header to the cylinder head. 

The question is, can I do a compression test and get reliable results in this situation?  I'm going to be removing (and likely replacing) the cylinder head.  At that point it should be pretty easy for me to check the condition of the pistons, rings, jugs, etc.  What should I look for in order to determine if I need to do a ring job, or should I just go ahead and do it anyway, since the engine has 41K miles on it?

Thanks,
BaileyMan

[Munkey]

The exhaust not being seated properly should not have any effect on a compression test.

If you're pulling the top end I would do new rings, hone cylinders, lap valve, & replace valve stem seals (these should be in your gasket set anyway).

[Baileyman]

Thanks Munkey,

Yeah, I planned on doing all that, and I was sort of figuring, as long as I've got all that stuff off, I might as well just get the cylinders honed and replace the rings.  It'll need it done soon, if not now anyhow.

It's good to know about the exhaust and compression test.  As I don't have a compression tester at the moment, and since I'll be doing the rings etc, it doesn't seem to make sense to buy a compression tester to see if the rings need replacing, but the knowledge will come in handy for sure.

I might start taking things apart tonight!

WooHoo!

Thanks,
BaileyMan

[Laminar]

Consider a compression leak-down tester. It will tell you exactly which component of your cylinder is the weakest link, instead of trying to guess whether or not a generic compression figure is good or bad.

[Munkey]

Thanks Munkey,

Yeah, I planned on doing all that, and I was sort of figuring, as long as I've got all that stuff off, I might as well just get the cylinders honed and replace the rings.  It'll need it done soon, if not now anyhow.

It's good to know about the exhaust and compression test.  As I don't have a compression tester at the moment, and since I'll be doing the rings etc, it doesn't seem to make sense to buy a compression tester to see if the rings need replacing, but the knowledge will come in handy for sure.

I might start taking things apart tonight!

WooHoo!

Thanks,
BaileyMan

If you need the service manual send me a PM.

[Baileyman]

Thanks Munkey.  I've got the service manual.  I just need to print up the pages I need.