Generally speaking - there's no way to remove a piston from the bottom of
the bore. The "webs" in the block for the cam bearing surfaces more or less
make this impossible.
What you really need to do is determine if what your onto here is your
basic "lost cause". If the thing is that nasty - you said there's rust on
the crank, right? - then forget it and go searching for another motor for
FWIW, I once spend something like 10 hours getting stuck pistons out of a
TR6 block. The pistons were siezed in a big way. As luck would have it, I
was able to yank off the rod and main caps and the crank just happened to
be in the perfect position to remove it with no interference.
Well, not only were the pistons stuck in the bores, but the wrist pins - er
gudgeon pins - were also siezed tight on four of the six cylinders. Well,
had those other two been frozen - well there would have been no way to get
the crank out. But I did it! And I'm actually still using that crank.
The point is - when I finally extracted all the pistons - I had to resort
to an 8 pound sledge hammer and a special "tool" that I stuck down into the
back-side of the pistons as a "hammering surface". Needless to say, those
pistons were useless after the operation.
I wound up picking up another block for that project, but I did go over
that particular block and I was able to salvage the block, rods, rocker
shaft, cam and various accoutrements. But the pistons were toast after 100
hits or so (each) with the previously mentioned 8 pounder.
Oh - and I had soaked the bores for something like 6 months with ATF and
kerosene and all kinds of stuff. Yikes!
Word to the wise - never buy a stuck motor. Period. And figure out when
it's time to "walk" from a lost cause.
Bob Lang | TR 6 Guy | Editor: New England Triumphs
Phone: | 617-253-7438 (days)| 781-438-2568 (eves)
Occupation: | ComputerZ | TR fixer-Upper