Hi:
Our 2008 C70 was overheated last month. Compression as low as 35 psi in five cylinders.
I pulled the head to check the gasket condition, anticipating more damage than that.
Really to check for warped head/block.
With what I have discovered, I believe I may be trying to talk myself into not donating the car...

The block measures .003 out of flat. I believe .002 is the max?
The head is way out of spec. It is more like .014.

Questions that I am looking for thoughts are:
Is the block too far gone?
Is the head too far gone to have it milled at a shop?
With this much head warpage, will the cam seats be warped to where even if the head can be milled, does this make the head unfixable?
It sounds like heating the head to straighten it has risks as well?

If your thoughts are that the block is okay enough I will forge on.
If the head is beyond machining, any suggestions on where to buy a replacement head?
I am not prepared to pull the engine and look for a replacement. My alternative is to just donate the car to a charity.

I appreciate any thoughts!

Thanks
Pete

 

Others can chime in but my two cents is that I've never heard of a block being warped - I'd just take the head to a machine shop and go from there to have it measured and comment whether it can be salvaged. You can also buy a used head - check out car-part.com for prices and yards who'd have one. If you are ok with doing the work yourself, it would be worth the added cost.

 

Not sure why you would think there are risks to straightening a head - it's a common procedure. A valve job is required after - but wouldn't you have that done with the head off anyway? And I've seen way more than .014 warped!

A head warps on the top and the bottom - so just surfacing a warped head leaves the cams trying to rotate in warped bearings.

 

Thanks Hoonk and MT6127.
Best I can tell just using a straightedge and feeler gauge, the block isn't flat, but not sure if I need worry too much with the .003.
I am all for working with the head and reconstructing if there is a reasonable chance of success
I'll check around central Ohio to find a machine shop that is familiar with straightening an Volvo aluminum block. (rather than just milling)

Thanks again
Pete

 

Definitely don't mill the head. the cam bearings would be 14 thousands out of alignment and that's a lot. It has to be straightened "enough" for the head bolts to pull it down, whatever that is. In other words it can be a thousandth or two off and you want to let the block straighten it the rest of the way. Obviously the cam bearings may not be perfectly straight either, but they need to be close. I would be pretty hesitant to change the block myself.