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Head pitted - Would you run it?

Progator135

Progator135

Regular Contributor
Motor was rebuilt after said damage tore up the cylinder wall...this is the old head. I have it on there now and running but just want to know the general consensus on the condition. The sealing surface is fine and the area around the plug hole is good. Ive smoothed the head out on flat surface and sandpaper. So no protrusions from the pits. theres about 8 PSI difference in the 2 cylinders. Im assuming from the pitting. Thoughts? 1985 50hp 2-cyl.
ATT_1446654670073_IMG_20150812_182554318-2.jpg
 
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If you'r absolutely sure that there is no metal embedded in any of those pits on the head, there's no danger in using it, BUT..... If there's just one piece of steel in any of those pits, it'll glow like the glow plug of a model airplane engine, and that usually results in pre-ignition which in turn will result in a melted aluminum piston, and you'll be back to square 1.
 
No sir, That pic was taken right after disassembly. It was thoroughly cleaned, smoothed, and inspected for any foreign material. So I should be good to go. Thanks for the input!
 
I've used lots of heads with similar (or worse) pitting. I seriously doubt the compression difference is related to the pits.
 
You can : A) have it milled .030 and git rid of most of the dingsor B) run it as carbon will eventually fill them in...
 
As far as the compression difference - its only about 2 hours into the 10 hour break in period - That should hopefully get better.
 
Boy I dunno. Hope all ya want, but I'd call 8 psi variance on a freshly "rebuilt" twin substantial. Not to sound like a smart a** but do you think break-in's gonna raise the compression in one cylinder and lower it in the other?

Agree on the head not being the cause. I'm running a nastier looking one on a V4 with virtually no difference in psi between the cyls.
 
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