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Chevy 350 heads valve seat pits

wanting to now what to do about these little pits, is it ok, while it have to be machined or is there a easy fix thanks

i think it had a bent valve in it

see pix’s

Just remove all doubt: take it to a machine shop and have all the seats and valves cleaned up.

Yep, the seats need to be completely smooth. Having the heads off is the hard work, the ‘valve job’ should be mandatory at that point.

Couldn’t he just lap the valves himself? I’m planning on doing that myself at home.

You need to have a complete valve job performed at an auto machine shop or you will probably have to take it all back apart again if you don’t. Prices vary by locale but around here the machine shop charges 5 dollars per hole (meaning one seat and the valve for that seat) and that’s very reasonable.

So you have 16 holes @ 5 bucks each for a total of 80 + valve seals. There would also be an additional charge for any valves or seats that may have to be replaced if they won’t clean up.

This is one of those ‘if you have to ask, take it to the expert’ kind of things. For $80 they can get the heads fixed up for long use, maybe find some problems that would have caused major issues.

That Mr. Goodwrench Long Block create motor is looking better every day…But you are in too deep now…

Save all your receipts so next year, you can write it all off your taxes as an educational expense!

thanks for the info , i took them both to c&p machine getting redone and valve guides thanks again. its going to be about 80

Frost, what year is that engine? Reason I ask is because if it’s a pre-1974 engine that was designed for leaded gasoline, then in addition to getting a valve job you should get hardened valves/seats installed. Because lead served as a valve lubricant in leaded gasoline of the past, unleaded gas will cause the valves to get burnt unless you have the hardened valves/seats.

i no the block is a 93 truck block so im gessing the heads are to ther tpi swirl port heads

OK, if it’s a "93 block w/ original heads you should have no problem with unleaded gas. A good re-grind of the valves and seats should do the trick. Another thing, and I don’t know if this is still done these days, but there was a procedure called a “3-angle valve job” that many performance enthusiasts had done to their engines to make them perform better.