Date: Tue, 28 Jan 2003 04:56:52 -0600
Reply-To: Open Wheel Racing <openwhel@BELLSOUTH.NET>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Open Wheel Racing <openwhel@BELLSOUTH.NET>
Subject: Re: Main bearings/rod bearings/bolts
Content-Type: text/plain; charset="iso-8859-1"
Hi Mike,
I didn't see any of the prior posts on this, so this may have already
been offered. I have a couple of questions. Do you know what type rings were
used? Were they chrome, chrome/molly, or cast iron? Is this a shop rebuild
or a home rebuild? Were the cylinder walls and pistons "miked", or were new
parts used?
I assume you mean to run this 5000 RPM's for ten minuets, "fix"
freewheel, in other words the van sitting still, engine running in neutral?
I would never do that to any stock engine! Maybe a "Blueprinted" race
engine, but never to a un-balanced, un-clearanced, stock engine.
If the engine was rebuilt using chrome-molly, or cast iron rings,
installed properly in properly honed, true cylinder walls, the rings should
have seated long ago!
I would guess that you have another problem such as: The cylinder walls
were not true, chrome only rings used, or something installed wrong. If the
mechanical items were right, and chrome only rings were used then you may
have a "seating in problem".Otherwise You may be out of luck.
Enough babbling, what should you do? Well you do have at least one
option that I know of. When Chevrolet first introduced their V8 in 1955, it
had a chrome ring "seating" problem. The recommended fix was to take a sock
filled with Comet, or Bon-namie (check spelling) powder cleaned, you would
hold the engine at about 2500 RPM's, and "pat" the sock in your hands
several times, causing the dust to be drawn into the air intake. The dust is
abrasive and would break the "glaze" in the cylinders allowing the rings to
seat. I have heard of this being done to large industrial diesel engines
also. Use caution here, only one application is recommended, and only if you
have "Chrome only" rings, not chrome/molly rings. I'm not sure if anyone
even makes chrome only rings for this engine, they are not very popular any
more because of this very problem. Chrome rings just wont seat on an un-true
cylinder wall they are just to hard.
It is easy to tell what type ring you have before installing them.
Looking at the "top" ring from the set, edge on. Chrome only top rings will
be shinny edge on, they are the hardest, harder than the cylinder walls,
lasting better, but will seat good only if the walls are true. Chrome/molly
top rings will be three layered edge on, a dark gray or black layer, chrome
layer, dark gray or black layer. They are a combination of the best of both
worlds, the molly seats quickly, the chrome is long lasting. Cast iron top
rings will be a single color, gray or black, no layers edge on. Cast iron
rings are the softest and seat very quickly, but only have about half the
life of chrome rings.
Anyway in my humble opinion, try the comet dust if you know you have
very straight cylinder walls, and chrome only rings. Because other wise with
as many miles as you have on the engine, ring seat is most likely not going
to be your problem, and a mechanical problem will be. Such as cylinder
walls worn out, a broken ring, ring installed upside down, ring gaps to
large, etc, etc.
I hope this is not information already offered, like I said, I missed
the earlier posts on this.
Good luck, let us know!
Howard
----- Original Message -----
From: "Mike Miller" <mwmiller@CWNET.COM>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Tuesday, January 28, 2003 12:29 AM
Subject: Main bearings/rod bearings/bolts
> Volks,
>
> Some may remember I got an engine rebuild that refused to seat the rings.
> Burned about a qt/800 miles. After many miles, 16000, I put in non
> detergent oil. No change. Someone recommended running it up to 5000 rpm
> for 10 minutes then letting it cool down slowing a couple of times.
>
> I did this once and the oil usage is 1 at/1500 miles. I'm tempted to try
it
> again but for my concern about rod and main bearings, and I guess rod
bolts
> as it's a 2.1.
>
> Any opinions, or actual facts, about this?
>
> Mike
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