Best way to judge a used engine?

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on-to-berlin
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Re: Best way to judge a used engine?

Unread post by on-to-berlin » February 26th, 2017, 12:45 pm

So working on the head now. I was grinding the valves. And after I tested them in pouring in gasoline. Howe, all of them except one did leak a bit through the intake and exchaust channel.
How much of valve play is accepted? I have grinded each one down until the surface was nicly even and toroughliy gray.
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1939 Harley Davidson U
1944 Harley Davidson WLA
1944 Willys MB
1969 Ford Mutt A1
1973 AM General Mutt A2

on-to-berlin
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Re: Best way to judge a used engine?

Unread post by on-to-berlin » February 26th, 2017, 12:46 pm

Horst, I tink I have a heavy duty head!

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1939 Harley Davidson U
1944 Harley Davidson WLA
1944 Willys MB
1969 Ford Mutt A1
1973 AM General Mutt A2

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rickf
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Re: Best way to judge a used engine?

Unread post by rickf » February 26th, 2017, 1:45 pm

That is a light duty head. Did you lap the valves in with lapping compound after grinding and what did you use to grind them? There will pretty much always be some seepage unless you have a competition three angle valve job done or a fresh valve job done with new valves and done on a valve grinding machine. It looks like you used a grinding stone in a drill? You will never get a perfectly matching angle that way unless the grinding stone is on a pilot anchored in the valve guide.

And he valve in that picture , while not real bad, will allow some gas to get by. If it were ground in a fixture then it would not. That being said that valve is not what I would call in bad shape, just a little tired.
1964 M151A1
1984 M1008
1967 M416
04/1952 M100
12/1952 M100- Departed
AN/TSQ-114A Trailblazer- Gone

on-to-berlin
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Re: Best way to judge a used engine?

Unread post by on-to-berlin » February 27th, 2017, 3:10 am

Rick, to me it seemed they are heavy duty.

The valves were grinded once again after I took this picture. So the valve rims were nice and evenly grey/clean without pitting. Thank you again for the advice. I still need more experince when it comes to used parts and how good they are. I have assembled some motorcycle engines with new parts and that is totally different as to working on used stuff and judging if it is still o.k. to use
1939 Harley Davidson U
1944 Harley Davidson WLA
1944 Willys MB
1969 Ford Mutt A1
1973 AM General Mutt A2

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