pistons go in from the top.
thats all!
----- Original Message -----
From: Bob Howard <mgbob@juno.com>
To: <BobMGT@aol.com>
Cc: <mgs@autox.team.net>; <mg-t@autox.team.net>
Sent: Friday, December 10, 1999 1:54 PM
Subject: Re: Trying to change a Piston with Engine and Crank in Place (TD)
> Hi Bob,
> I am pretty certain that the piston went in from the bottom at the
> factory, probably pre-connected to the rod. But, with the crankshaft in
> place you're going to have a very difficult time getting a ring
> compressor in there and getting the piston to enter the cylinder. I gave
> up on the challenge, removed the piston from the rod and pushed piston in
> from the top. In the original casting, there was probably some
> chamfering that made piston insertion easier. Once an engine is bored,
> though, that chamfer is gone.
> Somewhere I read that rods being in backward is a bad thing, and an
> explanation for it. Of course, I forget where any why, but a dim memory
> tells me that it had to do with the oil squirting out of the drillings
> and lubricating wrist pin or piston or cylinder wall....
> I would turn them around. That, of course, brings up the further
> problem that you may not know if the front of the piston is facing the
> front of the engine. Is the head still off? Can you see any markings on
> the piston tops? It could be that he is 180 degrees out with both piston
> and rod, so all you would have to do would be to remove bearing caps and
> rotate the rod. That sure would be nice, and easy. And unlikely,
> according to Mr. Murphy, discoverer of Murphy's Law.
>
> On Thu, 9 Dec 1999 23:44:32 EST BobMGT@aol.com writes:
> > As several list members advised, I was able to remove the piston and
> > rod from
> > the bottom past the crank. I found this had to be done on the
> > camshaft side
> > of the engine and it's a bit tricky. The crank rotation, piston and
> > rod all
> > had to be manipulated in order to "sneak" the assembly out. Once out
> > I could
> > not get a socket to go over the wrist pin clamp bolt because it's so
> > close to
> > the rod. Horst Schach in The Complete MG TD Restoration Manual
> > suggest using
> > an open end wrench, but my wrench couldn't get a good enough grip on
> > the bolt
> > and it started to round off the head. So next I tried grinding down
> > the
> > outside diameter of my 1/4 W socket as far as possible, but it still
> > wouldn't
> > fit. I then used the flat side of my Dremel cutting wheel to grind
> > down the
> > ridge on the rod adjacent to the bolt head. This provided just
> > enough
> > clearance for my modified socket to fit over the bolt head. This did
> > the
> > trick and I don't believe I removed enough metal to cause any
> > balance
> > problems (I hope).
> >
> > Now does the new piston go in from the top or the bottom? I can
> > envision the
> > piston going in from the top and pushed down just far enough to
> > allow the rod
> > and wrist pin to be attached from the bottom. Now that I can get my
> > socket on
> > the pinch bolt, I could tighten it with an extension. Or should the
> > rod and
> > piston be assembled and then installed from the bottom the same way
> > they came
> > out? If done from the bottom, can you get a ring compressor in there
> > past the
> > crank? If not, can one compress the rings with ones hands?
> >
> > By the way, the shop manual seems adamant about the rods being
> > assembled with
> > the pinch bolts on the right hand side of the engine. Naturally the
> > DPO had
> > them in the other way. Should I turn all the connecting rods around
> > the right
> > way or leave them alone?
> >
> > Thanks for all the advise. You should see how badly the old piston
> > is beat
> > up. No matter how I get the new piston in, it's got to be a big
> > improvement.
> >
> > Bob Donahue (Still stuck in the '50s)
> > EMAIL - BOBMGT@AOL.COM
> > 52 MGTD - under DIY restoration NEMGTR #11470
> > 71 MGB - AMGBA #96-12029, NAMGBR #7-3336
>
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