Valve seats with pits

Richard Lorenz

Senior Member
I am restoring an old block that was stored in such a way that some of the seats are pitted.

Is it O.K. to grind the valves but quit before all of the pits have been removed?
 
I am restoring an old block that was stored in such a way that some of the seats are pitted.

Is it O.K. to grind the valves but quit before all of the pits have been removed?

I assume you mean "grind the valve seats". I think it depends on what you plan to do with it. If it requires new babbit and you want to make a good runner and drive it, I would grind the seats until the pits are gone and if they are too deep too do that, have it machined for new seats. If you are not going to the expense of new babbit and just want to build a running engine then you may be able to just clean up the seats as best you can and run it. It WILL run with pitted seats.
 
I would get some seat cutters and clean the seats up - no need to grind them all the way down or install problematic new seats.
 
Is it O.K. to grind the valves but quit before all of the pits have been removed?

No not really. Carbon will begin to collect and before you know it, you will have a valve not seating which ultimately burns the seat & the valve. You did not mention whether the pitted ones are intake or exhaust. If on Intake side, just enlarge the seat(s) for oversized valves.



The difference between "grinding" the valve seats and 'cutting" the valve seats to remove pits is what???.

Time.
 
To save the block it would make some sense to now go oversize with the intakes if they are the ones that are pitted. But without seeing your problem first hand a pitted seat may most likely your exhaust seats. Other than saving the project you really don't need larger exhaust valves, larger intakes can add horsepower if you have the other components to go with them.
 
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