Date:         Wed, 13 Jun 2007 11:25:07 -0700
Reply-To:     David Kao <dtkao0205@YAHOO.COM>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         David Kao <dtkao0205@YAHOO.COM>
Subject:      Is this the cause of my engine compression problem?
In-Reply-To:  <3554AA2A2622F940A9E7998A5D6AF5220177100D@claymore.Advance.ColoState.EDU>
Content-Type: text/plain; charset=iso-8859-1

Over the weekend I put on another 360 miles to my newly rebuilt 1.9 engine.
I drove my 83 westy to climb some mountains in the western Sierra hills.
A bit disappointed. Did not get the horses I expected.

Today I checked the compression again. Very strange result. Last week I had
150, 150, 115, 150. #3 was 90 but when the engine was hot it became 115.
Today the readings are 60, 160, 150, 160 cold engine.

The #1 reads 60 PSI. The #3 now is healthy 150 PSI. No wonder I felt not enough
horse driving around some National Forest roads over the weekend. The strange
thing is #3 was poor and #1 was excellent. Now they swapped with each other.

I think I have an anwer to this. I would like your volks experts out there to
tell me if this makes sense, especially if you have seen it before.

My cylinder heads are in excellent shape (tight vlave guides and no damage to
valves and seats), But these heads are rebuilt heads from a VW dealer 30k miles
back. The gasket mating surfaces were ground and are perfect flat no pitting
whatsoever. But I now see a problem with them.

The distance between the exhaust holes of #1 and #3 as well as #2 and #4 are
now slightly shorter than normal due to the fact some metal was ground off
from the mating surfaces because of rebuilding. This should be fine except
now the exhaust headers (rear and front) are still at same length.

I remember when I reassembled the front exhause header it was very tight. I
basically forced it on to the heads. It was bolted on fine but it wass very
tight.

My guess is that the exhaust header is steel and is fairly large and strong.
It actually pushes my cylinder heads apart from the block. The #3 wasn leaking
last week. Now it shifts to #1. It basically pushed the #1 away from the block.

Has anyone seen something like this? Is this a rel possibility? I am thinking
to drop the engine again and take the exhaust header off to enlarge the holes
of the bolts. Or I will send them to a machine shop to bend it slightly so that
they will fit perfectly without working against the heads.

I am determined to fix this engine. This problem probably was introduced to the
engine when it was rebuilt by a VW dealer when it we at 80k. The engine never
regained horses. Now with a new liner and good heads it still doesn't work
right.

What do you volk experts think? Is it reasonable to suspect that the exhaust
heads are the cause of this problem? Thanks in advance for comments.

David















____________________________________________________________________________________
Building a website is a piece of cake. Yahoo! Small Business gives you all the tools to get online.
http://smallbusiness.yahoo.com/webhosting