Hello redsox;
It is a BAD idea to run new valves on a used seat BECAUSE, the seats are ground a certain width and certain angle and the surface of that angle is FLAT.
At an idle speed of just 1000 rpm’s, each valve beats the cr_p out of the seat at a rate of 8.333 times per second or 500 times per minute and vise versa. At an average cruising rpm of around 3000, each valve beats the cr_p out of the seat at a rate of 25 times per second, or 1500 times per minute.
After the valves beat the cr_p out of the seats on and off over a period of around 27 years etc., the seat becomes less than an ideal "sealing" surface.
If you are/were able to lap the valves to a point that they do/did seal, they still will NOT last as long as they would if you were to have the seats re-cut.
Nope, lapping new Japanese valves will NOT "junk" your engine. Simply scrub the seating surface of the valve with a brass “toothbrush” and carb cleaner, then brake cleaner, and they will be un-mojoed and have no compound left on them. AFTER the seats are PROPERLY cut, you can lap them in again with fine compound and it will easily clean off.
Sure you can, just by some “unlapping” compound then turn them in the opposite direction from which you used to lap them with.
To what, your cylinder, your valves or your cat by throwing the poor thing out in the snow simply because it kept trying to lay on top of you while you were sleepin so it could get warm?
That’s good, because you’ll need that expertise when you are measuring how far out of round and tapered and possibly BIGGER your cylinder is after you use your hand held hone on it.
Everything EXCEPT for your cylinder honing plan AND your valve seats in my “humble” opinion.
Sure.
PS – Perhaps you like my baby pig photo more than the others. I named her “Bacon”.
Hi, my name is Bacon. Aren’t I cute?
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Yes we need to get things together too, FABZ and I spoke recently and mentioned how tight this late winter is hurting us. We gotta get outside!!