On Thu, 18 Sep 1997 17:53:08 -0700 "Frank R. Krajewski"
<FrankK@businesson.com> writes:
>Always thought that the drill spun too rapidly to be effective and
>that
>the slower hand motion was better. I have, on occasion, used the drill
>method but was told it was not as good as the palms! What does your
>experience tell you?
>Frank Krajewski
>1980(LE), 1974, 1973, 1964 MGBs
>1958, 1961 Bugeye Sprites
>1958 MGA
>1972 MG Midget
>1952 Hillman Minx Sedan
Frank,
the key here is LOW speed. Don't use the $29.95 single speed motor. it
is just too fast and can damage the seats/valve faces.
I use a Craftsman 3/8" VSR drill and just barely press the trigger. The
motor turns actually slower than I would with the palm method. I also
raise the valve off the seat slightly about every revolution or so.
I've built several engines this way and (knock wood) so far haven't had
a failure or problem that was tracable to poor valve seating.
The engine in my 74 Midget has about 95K miles on the head since it was
done, and my son's 73 has about 40K since it was done. His did have a
problem but it turns out it was a sticking valve caused by my (former)
machinest not sizing the guides with the proper clearance.
I've just finished building a 3.5L Rover for a friend's racer. The
previous version held up well. At least untill the camshaft decided to
give up the ghost.
Care and patience is the prime requisite, even though the drill method
is faster, it ain't that much faster
Good luck
Rick Morrison
72 MGBGT
74 Midget
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