boovuc 1,090 #1 Posted March 6, 2015 Here is a picture of that rear cylinder over-sized valve and seat cleaned up a little. Check out the "holes" around the intake seat. They are only surface holes. No depth to them. They go all around where the machine shop/dealership repaired this intake seat for the first owner. What is this all about? Ever see these on a repaired valve seat? Share this post Link to post Share on other sites
Howie 882 #2 Posted March 6, 2015 I think they tooka a sharp punch and went around the insert to peen it in more. Thinking that would help keep it from coming out. David 1 Share this post Link to post Share on other sites
Callen 64 #3 Posted March 6, 2015 That is called peening. it's done in this area to tighten the seats. Share this post Link to post Share on other sites
boovuc 1,090 #4 Posted March 6, 2015 When you peen a valve seat, you usually don't put more than four or six "peens" making sure you drive them cross-ways from one another. There are 14 drives on the bottom alone and you can see how many there are on the top. I wonder how out of round this seat is? Crappy work on this repair!!!! Period! Share this post Link to post Share on other sites
Callen 64 #5 Posted March 6, 2015 agreed. Wonder if they were trying to move it away from the cylinder to get it lined up with the guide? Share this post Link to post Share on other sites
Pickle 42 #6 Posted March 6, 2015 I believe someone mentioned the seat had been replaced twice, hence the extra peen marks from the first installed replacement seat. 2 Share this post Link to post Share on other sites
boovuc 1,090 #7 Posted March 6, 2015 I don't know Pickle. It was .060 over on the second repair to also repair a crack in the block. I would have thought those peen marks would have been obliterated on the bore-out. Share this post Link to post Share on other sites
boovuc 1,090 #8 Posted March 7, 2015 It looks as though most of the peen marks on the bottom of the seat are half to three-quarter obliterated while the top peen marks are mostly there and to my eyes are not even on the seat. This is what I don't understand! Share this post Link to post Share on other sites
JackC 616 #9 Posted March 7, 2015 If the valves are adjusted properly and if the valve and seat are cleaned up and have no carbon residue and if the cylinder passes a compression test then it would seem that it should be OK? If a valve is out of adjustment such that it does not close on each cycle then it would seem that there is a higher probability the cylinder will overheat and the seat can come loose from the block? Share this post Link to post Share on other sites
