Date: Fri, 17 Jan 2003 09:14:20 -0600
Reply-To: John Rodgers <j_rodgers@CHARTER.NET>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: John Rodgers <j_rodgers@CHARTER.NET>
Subject: Re: Replaced Rings blowing oil
Content-Type: text/plain; charset=us-ascii; format=flowed
Hello Eli!
Any time you pull a cylinder barrel because of ring problems, and you
want good performance when it goes back together, you should always hone
the cylinder barrel, and install new rings. The cross-hatching of the
honing makes little grooves that catch oil and the iron ring face will
wear against those cross hatches with plenty of oil there to help
prevent galling of the two metals. As the engine is run the raised
surface of the cross hatching will "wear-in" as will the ring face and
the fit between the ring and barrel will become closer and closer. This
is why a new engine will use a little oil before it is broken in well.
It is also why a "break-in" oil is used for the first few hundred mile.
There will be a lot of metal flakes worn off that will get into the oil,
and the break-in oil - usually a straight 30 wt, will give a stronger
separation between the parts to help reduce that initial high wear. As
the parts "wear-in" a switch to a finer oil with different wear
characteristics that gives better protection to closer fitting parts is
necessary. In my own engine when it was rebuilt and run for the first
time, I ran a straight 30 oil for several hours or so in the shop
while everything was being adjusted and checked out and brought up to
temperature. Then I changed the oil and filter, putting back in new 30
wt break-in oil. I drove it for 500 miles, then changed the filter and
oil again, drove for 1000 miles, then changed filters and went to
20W50WT pil and have been running that ever since. I have never had a
lick of trouble with that engine of itself. A few problems with the
peripherals, but not the engine.
Only once have I ever attempted to do what I consider major work on any
of the VW engines without first pulling it from the car. That first time
was lesson enough. You will be able to do a far better job on the engine
if you take it out where you can REALLY get to everything, although I am
sure some will take the opposing view. It's just my opinion based on my
own experience.
As for the tools you mentioned, I can't help you there.It has been a
while and my stuff has gotten scattered. But some of the fellows on this
list have to know how to tell you how to make the tools and I am sure
they will graciously help.
Good luck,
John Rodgers,
88 Gl Driver
Eli Secor wrote:
>OK, this is my first posting and I'm afraid it's a deuzy! (sp?)
>
>I recently replaced the heads on our (newly acquired) '85GL and ended up
>having to pull sleeve #1 and #4 with the heads as no amount of coaxing or
>tapping would seperate them. In the process I broke the top ring on #1 and
>ended up replacing it along with the oil wiper. I have everything back
>together and all works well (no coolant problems) except that I've gone
>through about a quart of oil in the last 300 miles. I tested compression
>and found the following: #1 - 100psi, #2 - 157psi, #3 - 127psi, #4 - 162psi.
> #1 was noticeably oily on the tip, leading me to believe that my oil loss is
>through that cylinder (there are no leaks as far as I can tell, and the damp
>exhaust at startup seems to have little oil fleks in it). A local shop told
>me that the new rings on #1 might never seat, and that I should pull the
>pistons & sleeve to replace all the rings, check the tolerances, and to have
>it honed and seated.
>
>My questions are:
>1. Does this sound like good advice?
>2. Where can I find the circlip, piston pin, and crankshaft arm positioning
>tools? The local dealer won't even touch my car, let alone stock tools for
>it. I suspect I can get a stock circlip tool and improvise the crankshaft
>arm tool, but is there a home remedy for the piston pin tool?
>3. I believe I have to pull piston/sleeve #2 to get to #1 - does it make
>sense to pull the whole thing apart, replace all the rings, and have a
>machine shop seat them all?
>4. Source for reasonably priced head gaskets (only)? Last time I bought a
>complete gasket set for about $150.
>
>Any advice would be very much appreciated!
>Eli & Amy - VW Newbies
>
>
>
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