rothlane'68

I recently got my rebuilt cylinder heads back from the machine shop. Last night I was working on putting the passenger side head back on the motor. I was chasing head bolt threads and wiping everything down and it was at this point that I think I may have made an expensive mistake...

I was using a pick to clean some rust and scale out of the small coolant passage at the center of the block (see pics) and the pick slipped. I made myself a scratch from the coolant passage over to cylinder 6... its very shallow, you can't feel it if you run your finger over it and you can just barely catch a finger nail on it if you try hard. Will the gasket seal this or have I just made my winter project much more interesting and expensive???

This is not a high compression application and I am (or was!) using the standard blue felpro gaskets.

Thanks in advance!

p.s. Don't mind all the dust (from a blue scotch brite pad i probably shouldn't have been using) i have since blown everything out with air, vacuumed it off, and wiped it down with acetone on a microfiber cloth for good measure. Everything is surgical clean.

tru-blue 442

I wouldn't worry about it, it should seal just fine.

matt69olds

I would think it will be ok. Go over the deck surface with a short piece of C channel and some 600 grit sandpaper just to make sure there are no high spots.

I doubt you could scratch the deck surface deep enough with a pick to affect head gasket seal. I bet once you go over it with some sandpaper, you might be able to see the remains of the scratch, but not be able to feel it.

rocketraider

The FelPro blue should seal that.

My bigger concern is why the machine shop didn't get the crud out. I know hot tanking is frowned upon now and even illegal in some places. I've never thought baking the stuff off got castings as clean as a good hot caustic soak.

rothlane'68

Thanks guys, I'll stop holding my breath now!

Sorry if I wasn't clear, the block stayed in the car, the heads went to the shop. They're pretty clean. I believe he said they were baked and and then shot peened. I did find a few holes in them that needed a good chasing with a tap (which did make me wonder), but in general I was pretty satisfied. I would agree, a caustic soak seems like it would do a better job.

cutlassefi

If that “scratch” goes down into either the bolt or steam hole then it’s a crack, not a scratch.

BillK

I would be more concerned with the residue from the Scotchbrite pad. Those things are a no-no around engines. Make sure and run each piston up to the top and use your shop vac to vacuum all the way around each one to make sure not of that crap is down between the piston and the cylinder.

rothlane'68

Its definitely a scratch, I did it with my own two clumsy hands.

Thanks Bill, will do, this is something else I learned after the fact! I already vacuumed everything off and washed everything down with WD 40, ran the cylinders up and down and wiped everything multiple times, but I'll probably go over it again for good measure.