How flat is flat? ‘88 Force 50HP cylinder head

[WalleyedNJ]

Blew a head gasket due to the PO not torquing the head bolts properly.

Head is is out of flat by .007” with the low point being between the cylinders. Is that within tolerance or do I need to surface it? I’m unable to find a reference anywhere.
Thanks!

 

[Scott Danforth]

You need to surface the head. I believe tolerance is about .001

 

[WalleyedNJ]

You need to surface the head. I believe tolerance is about .001

Got it to < .0015. That’s the thinnest gauge I have.

 

[jerryjerry05]

Just put it on.
It's soft aluminum and it will fit.
Never have I had to mill a head to make it fit.
If you want to mill anything the block where it meets the head or if the exhaust cover's been removed? then those surfaces should be milled.
The heating and cooling has eaten the edges and when reassembled it 's harder to reseal if the surfaces aren't milled.
I have never has an exhaust chest not leak when reassembling, the milling really helps.