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Joined: Apr 2009
Posts: 288
Apprentice level 3
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Hi all, I have striped down a relatively unused briggs quantrum engine (the one i was trying to calculate the hp on a few weeks back). i have found all the bearings are in great condition, but the exhaust valve and seat was Heavily pitted. the seat has a few pitments and a chip that is about 1 mm by 1 mm at the base of the seat. the valve was totally buggered so I found one of the same length and same size accept it had a domed cut in the top. After fitment it seals enough to hold a small amount kero with minimal seepage. Anyway what I want to know is it worth lapping it in further even thought it still has a chip or just forget the whole thing (im not prepared to go thought the torment of regrinding or replacing the seat!). All opinions gratefully taken! Thanks allot Regards jay
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Joined: Dec 1999
Posts: 5,382 Likes: 34
Repair Junkie
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mowernut, I was going to suggest you buy a valve seat cutter until I looked up the price. They start from around $800 + and up to about $2000. If you were not far away I could cut the seat for you as I have a set. 
Regards, ![[Linked Image]](https://www.outdoorking-forum.com.au/forum/images/members/mower-monsterw.jpg) Bruce Please do not PM me asking for support. Post on the forums as it helps all members not just the individual.
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Joined: Jan 2009
Posts: 6,926 Likes: 10
Pushrod Honda preferrer
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You can't lap out a chip, you'll just ruin the new valve trying. Does the new valve have the same seat angle as the valve seat? I see you are in Melbourne. I live in Melbourne and have a set of Warren & Brown cutters that I inherited ten years ago and have never had occasion to use - I haven't worked on valve seats in more than 30 years. I don't know whether I would have the right seat angle, let alone the right pilot diameter. If you can find out what both of those should be, I'll see if I have them.
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Joined: Apr 2009
Posts: 288
Apprentice level 3
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G'day, I have located another identical engine so I shall make one out of the two using various parts. Thanks for you help Bruce and grumpy. Regards jay
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Joined: Jan 2009
Posts: 6,926 Likes: 10
Pushrod Honda preferrer
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Sounds like a good solution jay - recutting seats that have had sizeable chips out of them results in deep-seated valves, and the valve seat inserts can be weakened as well.
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