Subject: Re: To Teardown or Not Teardown?
Author: Bruce Giller
Date: Oct 9, 2002, 6:58 AM
Post ID: 1711174246
Keith,
Last winter I rebuilt the 4 cylinder engine from my '73 Alfa Romeo GTV.
The engine was stripped down to the carcass and then reassembled. This
was my 1st engine rebuild of any kind - the most intricate operation
before has been to remove heads and cylinders (cars and bikes). And the
bloody thing actually ran after installing it back in the car - I almost
fell over when it cranked over and started.
Being that this was my first rebuild, I got help from the Alfa-digest
members, shop manuals, and a local Alfa mech. where I bought parts. But
all the assembly work was done by me in my garage - a machine shop did
the work head and crank/rod/piston/clutch balancing. I did have to redo
a few steps (several times, mind you) and ruined more than one seal
trying to install it.
But I took my time, put all the removed parts into zip-lock bags with
enclosed notes, measured everything about 5 times to make sure I got it
right, and asked lots of questions. Even got to buy some new tools - an
engine stand, for one. Not rushing things seemed to help the most.
It looks like a big job but if you just break it down into small steps,
then it isn't all that imposing. If you don't know how to tell if the
bearings are shot, just zip a note to the list and ask - my answer is
just replace them since I believe that they are plain bearings (not ball
or roller). A machine shop can measure the crank, rods, pistons for
you; you give them the specs for them to work from.
Get the shop manual for your ambo and start reading. Guzziology is
great for indicating where upgrades can be applied. And the Loopframe
list members can answer all the rest of your questions....or know where
to get them.
My biggest discovery is that it just isn't rocket science - you might
put a scratch somewhere that doesn't help matters but it doesn't mean
that the scratch will prevent the engine from working. Example: after
getting my parts back from balancing, I discovered that the rod's big
ends were too 'fat' and needed to be reduced by about .003". Sent a
note off to the alfa-digest and an engine rebuilder said that he used to
hand file them to spec (until he got a machine to do the work). That is
exactly what I did - filed only on one side and measured with a
micrometer until correct (then polished them a bit to look nice). Found
out that the original machine work from the factory didn't have the two
sides perfectly parallel anyway....
Bruce
'72 Eldo
Keith Ruff wrote:
Spoke with Andy last eve and may hook up with him sometime as he is in NJ frequently. Tried for the past few days to contact Dave Otis and have not head back from him, so I am guessing he is either busy or not interested in taking on the project. Figured I will start looking at backup plans until I hear from Dave. My biggest fear with tearing down the motor is not messing anything up along the way, i.e., scratching surfaces like the cylinder walls, and also, knowing what I am looking for as far as bad parts. I don't have a clue how to know the bearings are shot, if the crank needs to be machined, etc... so it would be like disassembling and not knowing what to do from there. Also don't have any special tools that may be needed to disassemble/re-assemble. How do you get the pistons back into the cylinders without scratching the walls, should any upgrades/mods be done while I am in there, can the piston heads and valve stems be de=carbonized, etc. etc. etc. Would like to venture into this but envision a motor in pieces on the floor with no clue what to do. What should I do? Would love to have someone experienced stay at my house for a good week to assist in the teardown, diagnosis, repair, and re-assembly, have offered this to Andy but not sure if he has the time to stay here a few days or if that is enough time to do this work. Keith Ruff 71 Police Ambassador - NJ |