Measure valve stem = (a shallow) .310 all the way up and down the valve. It's straight.
I found a precision ground "pilot" that measures (a heavy) .311 which I'll use to determine the correct clearance for this Intake Valve. I'll hone the new guide until this pilot just fits in each end of the guide(all the way through) - then I'll know I have the correct clearance, so he don't stick the valve.
The
Sunnen HONALL is a miraculous invention. It hones these Rowe cast iron guides perfectly. It's honed hundreds of guides from the old
Noots' Custom Cycles days . . . and it's still in use. They ain't cheap, but it's better than a reamer. Cast iron guides have better lubricity than steel guides.
The pilot fits in both ends . . . and the valve has proper fitment.
Now I'll hone the Exhaust Guides, cut the seats(you can see they're pitted) and we'll have a fresh set of heads, ready for another 30,000+ miles - (hopefully)with today's unleaded fuels.
4 comments:
Is that micrometer an old lufkin? Looks like the dark green color of my old set.
I think it is. Most all the measuring devices I use are from my dad's machinist years of working at a tractor manufacturing plant. Oliver/White Farm Equipment.
Which stem-to-guide clearance to you use for the exhaust?
I give it about +.0025 with cast iron guides, and nitrite valve. A little more (+.003)with steel guides, no nitrite. All my heads, and engines don't smoke, or burn oil. I don't use valves seals. Some guys that want seals, I'll put them on the intakes only. Seals mean I have to "think" more, but I'm getting better at it. Do it right and you'll be much happier in the long run.
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