Subject: Re: To Teardown or Not Teardown?

Author: Martin Cooke

Date: Oct 9, 2002, 7:56 AM

Post ID: 1711174680

Martin,
I wasn't reducing the diameter of the 'hole' in the big end but the
width of the big end; the spec called for measuring the gap between a
side of the big end to the journal shoulder on the crank with the rod
bolted to the crank (the wider the gap, then more oil can get in there).
To file, I bolted the end cap to the big end, and filed across the flat
sides of the big end. I sure wish that I had done the measureing BEFORE
I sent them off to the machine shop; then they could have done it.

Bruce

Martin Cooke wrote:

i was agreeing wholeheartedly, right up to the bit about filing the

surfaces (i think) of the big end eye. the word OVAL sprang unbidden to

lips.

then i thought it was probably better than how alfa (or indeed guzzi)

have made irt in the first place and i'm sure it works fine.

cookie

ps. i was at the guzzi factory last week, and was shocked to find they

a fair number of newish CNC machines on the shop floor like ducati.
whatever happened to Luigi & his hammer & chisel eh? maybe big end eyes

round now.

----- Original Message -----
From: "Bruce Giller" <bgil-@mitre.org>
To: <Loopfram-@topica.com>
Sent: Wednesday, October 09, 2002 2:58 PM
Subject: Re: To Teardown or Not Teardown?

Keith,
Last winter I rebuilt the 4 cylinder engine from my '73 Alfa Romeo

The engine was stripped down to the carcass and then reassembled.

was my 1st engine rebuild of any kind - the most intricate operation
before has been to remove heads and cylinders (cars and bikes). And

bloody thing actually ran after installing it back in the car - I

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.

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

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

right, and asked lots of questions. Even got to buy some new tools -

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

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

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

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

hand file them to spec (until he got a machine to do the work). That

exactly what I did - filed only on one side and measured with a
micrometer until correct (then polished them a bit to look nice).

out that the original machine work from the factory didn't have the

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

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

interested in taking on the project. Figured I will start looking

backup plans until I hear from Dave.

My biggest fear with tearing down the motor is not messing anything

along the way, i.e., scratching surfaces like the cylinder walls,

also, knowing what I am looking for as far as bad parts. I don't

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

to do from there. Also don't have any special tools that may be

to disassemble/re-assemble. How do you get the pistons back into

cylinders without scratching the walls, should any upgrades/mods be

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,

re-assembly, have offered this to Andy but not sure if he has the

to stay here a few days or if that is enough time to do this work.

Keith Ruff
71 Police Ambassador - NJ

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