Valve lapping

[1930artdeco]

OK, I searched but could not find an answer to my questions. I am beginning to lap the valves and am using some lapping compound that the machine shop gave me-Permatex. So I started on #1 ex as a test. I have a ZIM hand crank lapper but it would not even budge the valve-even after I put oil on the stem and worked it around by hand. So, I used the long stem and did it by hand-worked decently (I just bought the wood stick version). The guides and springs are in aaand so are the keepers-my knuckle head exuberance. So I will take them out one by one and lap them. My questions are:


1) I know I am looking for a thin stripe around the middle of the valve that is nice and shiny. But after a few rotations I looked and it look really rough with the shiny parts at the top and bottom of the valve. I assume this will go away as they seat together?


2) How long should this take per valve? I don't want to just keep going and ruin a valve and seat.


3) Best way to get the compound off the seat and valve?


Thanks,


Mike

[redmodelt]

New valves and fresh cut seats? Three face seat or single? Any time I have lapped valves, I see a gray ring around the sealing edge, not shiny. Does not take long, just looking for no missed spots on valve or seat. I clean up with mineral spirits. I rub the valve laper between my hands, lift/turn some and repeat. If your seats are 3 face you really do not need to lap, the rotation of the valve will seat itself. (So I have been told )

[Bob C]

Here's a video on lapping. https://www.youtube.com/watch?v=Ufou8RMAvlo


Bob

[Patrick L.]

Before lapping I would suggest checking the face to seat contact with pencil. 3 or 4 strokes with the pencil across the valve face then rotate a bit in the seat and look at the contact. It should be slightly toward the stem from the center of the face and .060-.080" wide for intakes and .080-.090" wide for exhaust. If they are not correct then a seat grinder/cutter is used to change the contact point and width. Once the contact points are correct then a slight lapping can be done, but, its not needed.

[d.j. moordigian]

Originally Posted by Bob C

Here's a video on lapping. https://www.youtube.com/watch?v=Ufou8RMAvlo


Bob

I couldn't get past the half way point,...Bob this video is BS...!!

...................................don't do this !......................................

[1930artdeco]

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Hope these come through. Here is the valve and seat. Both are even all of the way around. Will keep going this weekend on her. I won't let me upload the pic of the seat for some reason. Will try later.

Mike

[BILL WILLIAMSON]

Originally Posted by d.j. moordigian

I couldn't get past the half way point,...Bob this video is BS...!!

...................................don't do this !......................................

Listen to Dudley, he's a EXPERT! Some Folks are BULL-SHITTERS!
Bill W.

[Synchro909]

Originally Posted by d.j. moordigian

I couldn't get past the half way point,...Bob this video is BS...!!

...................................don't do this !......................................

You did well to last that long! He says this was done by a profesional. Profesional what?