Topica Loopframe_Guzzi Archive


Subject: RE: The Big Bang!!

Author: Kevin Graf

Date: Sep 12, 2002, 7:14 AM

Post ID: 1710996274


Kieth,
Drain the oil into a clean pan. Starting with a clean pan will allow you to
know what exactly came out of your engine. with the pan off, look to make
sure the connecting rod nuts are still there, 4 total, 2 each rod. Look
around the bottom of the pans for anything. Metal flakes, pieces of metal,
anything out of the ordinary.
If you don't find anything at this time that shows the problem your looking
at a teardown.

The "shells" are the bearings, also called plain bearings. There are no
rollers, or little ball bearings in a cage. These bearings are a strip of
soft metal, oil creats a thin buffer between the bearing and the rod. In
order to get to these, your talking pulling the top end, Rockers, heads,
cylinders. Then undoing the 4 rod bolts. Each rod will come out in 2
pieces.Yup, their called 2 piece connecting rods. The Big End part of the
rod is what mates with the crankshaft(2 piece end). The Small End is where
the piston is attached to the connecting rod. The big end bearings are the
plain bearings your asking about. There are 2 peices per rod. One on(in) the
"cap" the other on the rod side. All these parts should be taken apart with
care and it should be noted how and where they came off and marked
accordingly, since mating surfaces should not be interchanged.
The big end bearings should be intact and smooth, Although, There will be
some wear and grooving. From what it sounds like, your problem seems like it
should show itself to you without too much detective work.

If you decide to do this, I should tell you that before you start tearing
everything apart you'll want to check for up and down play in the rod
bearings. This can be done when the top end is off. You'll want to grab the
small end of the rod(preferably without the piston on) and pull straight up
and down. Any up and down play is technically bad and the bearings should be
replaced. Take your time with this as the side to side play will want to
fool you. Just the up and down matters.

If you take your time and inspect & label every part you take off. From
start to finsh, look at everything! It's not rocket science, just your basic
internal combustion engine. In my expirance, people have a better connection
with their machine if they learn about it and do it themselves. That way YOU
KNOW whats going on in there, and everything starts to makes sense on how it
all ties in together. If(when) it breaks down again you'll be able to look
at it with a new prespective.

Hope this helped...
Kev
-----Original Message-----
From: Keith Ruff [mailto:klru-@fcc.net]
Sent: Thursday, September 12, 2002 9:22 AM
To: Loopfram-@topica.com
Subject: RE: The Big Bang!!


Bottom end has never been apart, bike sat for a long time, so maybe
there is sludge. I'll pull the oil pan and check things out. What
should I look for? How do you know if the bearings are bad? I just
looked in the Chilton manual I have (it's an old early 70's vintage
book) and I can't tell what the bearings look like, unless they are the
"shells" they speak about, or do these shells go around the bearing?
How do you get the bearings out? Are we talking total engine
disassembly here or can this be done working from under the bike with
the oil pan off? I do see in the book the little oil holes on the arms,
is that the ones that can clog and starve the bearings of oil? If they
are clogged how can they be unplugged while in the motor, or again, does
this require engine disassembly? Anybody up for a road trip to
NJ???????????

Keith


Fred Sahms wrote:
 
Keith Ruff wrote:
 Well, as I feared most, that metallic noise/clacking while riding has
come to fruition. -snip

Sounds like a rod bearing or two. I don't know your history with this
bike: has the bottom end been apart since you've owned it? The sludge
trap in the cranks on the non-filter models are prone to being plugged
with sludge, starving the rod bearings of oil.


73 Eldo (motor finally together)
78 T3/949

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