Head gasket failure?

[vtl]

. Would the straightedge and feelers be used for this?

Yes.

[volvolugnut]

This is where I suggested starting with a carpenters framing square and feeler gauges. Perhaps $30 if you have to buy both. Minimum machine shop charge might be $50-100??? Start low tech and work up if needed. If the cheap tools show you have huge gaps then your head is likely junk. And you will still have a framing square and feeler gauges.
volvolugnut

[cfoss]

I don't like the idea of a carpenter's square for this work. It could lead you to the wrong conclusions.

You can get a precision straight edge for like $50 on Amazon. Plus a set of feelers for $20. Can't beat that really.

Checking for flatness is super easy. I've done it multiple times. The block could be warped- VERY unlikely, but possible if the car has been severely overheated.

Otherwise it's just the head. And they are usually fine too, unless massively overheated. Look for less than .003 inches of gap with a precision straightedge.

Then you can check your carpenter's square against the straightedge

Also, if you switch to a MLS head gasket, make sure to prep the surfaces to a low RA rating-Typically this corresponds to a 600 grit or finer north american rated sandpaper. Many machine shops will not have machines which can produce this fine a finish.

If you go the sandpaper route, make sure to have a FLAT block behind the sandpaper.

Hope that helps,



Chay

[kallekula]

If it’s a serious machine shop that will skim it they wouldn’t work on it if its 12 thousands of an inch warped or more.

[abscate]

Correct on that. If it’s mire than 0.010 inches or so , you can have it thermally straightened. Clearwater did this for me on a head two years ago for $600