How should I feel about this valve seat replacement job please?


New Member
Hi all,

I've just had a flat head worked on. There was a fair bit of rust under the head and you can clearly see one of the valves had been cut quite deep into the block (earlier repair of major damage?). I'm posting before and after pictures. Not sure how I feel about the work done. One of the seats is massive in comparison to the others and has a trough around it. Not sure if it has enough material to stop it falling out but he's supposed to know what he's doing. I guess the machinist has tried to get all the valve seats back up to the same level and the dirty looking repair was a necessary evil. Would appreciate the feedback of the experienced guys on here please...



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The Grumpy Grease Monkey mechanical engineer.
Staff member
first you have to admire the stark simplicity of the flat head 4 cylinder engine design, you can't get much more basic in an engine design and easy to work on , as to the valve job, it looks like they (the machine shop) did a good job, and from way I see it looks like you could do some port to under valve seat clean-up to increase port flow potential but considering the age of the engine it looks to be in rather remarkable condition.
I think the machine shop did a good job.
can you post a few down the valve throat and down the intake runner/ back of the valve seat pictures?
as to the recesses area behind the valve seat insert I doubt it will cause you any issues.
btw what year and make & model engine is that? I had a rather similar looking 1965 rambler with a roughly similar looking 6 cylinder flat head


New Member
Thanks for your encouraging words Grumpy. I like things to feel right and was a little disappointed with the results when I saw them. Have never seen such an extensive valve repair before. If an experienced guy like you thinks it's OK then I feel better about the job. Unfortunately it will be a few weeks before I get down there to take my own pics. I can see that the seat in question looks to have more material depth than the others. Do you think there's enough interference there to stop it jumping out when hot? That's my main concern.

This is a 1944 Willys Go Devil Jeep engine by the way.


The Grumpy Grease Monkey mechanical engineer.
Staff member
I kind of thought it was a Jeep engine, as I've worked on a few jeeps 4 decades ago!