Date: Sun, 27 Nov 2011 21:27:35 -0500
Reply-To: Gregg Carlen <gregg.carlen@GMAIL.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Gregg Carlen <gregg.carlen@GMAIL.COM>
Subject: Head and valve condition
Content-Type: text/plain; charset=ISO-8859-1
Hey folks,
I'm looking for some advice about reusing the head I just removed from my
2.1l (1990 Westy 2WD). 185k on the engine and the heads and engine have
never been rebuilt as far as I know.
The PO had been running the incorrect coolant, which I changed out this
past summer with Sierra, however, it was too late. Had a slow head leak
(more like seeping through the gasket) starting already. Finally got around
to pulling the head this past weekend to prepare for a gasket replacement
(and green o-rings on the cylinders, all other usual gaskets replaced,
etc).
When I pulled the head, I was initially pleased with the condition.
However, upon closer inspection, I notice a few things that make me wonder
if I can re-use the head as-is, make a few repairs, or have to replace it.
This is the passenger side head.
My initial observations were:
- the gasket surface was in very good condition. Only a few small spots of
the slightest pitting.
- The oil cavities only had the slightest tarnish from oil. Wiping with a
cloth removed it.
- All of the coolant and oil cavities seemed to be clear and clean.
- There was only the slightest bit of carbon in the combustion chambers.
- The head gasket was the source of the leak, not corrosion on the head's
mating surface. - - The gasket had essentially turned to putty and started
to deteriorate and like an old sponge (I could see the 'spongy' look from
the outside before I pulled the head).
Upon closer inspection, there were a few areas of concern I noticed:
- Between one pair of intake/exhaust valves, was a very small crack. I'd
say it's not quite wide enough to insert the edge of a piece of paper.
- Between the other pair of valves, I noticed a hairline fracture if I look
at it from just the right angle. Not a crack, just a fracture.
- Lastly, the contact surfaces between the valve adjustment screws and
valves looked good, with the exception of one. The contact surface between
one exhaust valve and the adjustment screw had lost its original shape just
slightly. Almost didn't notice it at first. The adjustment screw has the
slightest mushroom effect on it and the contact surface of the valve end
isn't mushroomed, but doesn't have the crisp edges like the other 3 valves
do.
So, all that being said, I'm thinking I'm okay to clean it up and
re-install (I hadn't removed the valves and wasn't really planning to). I
am, however, a little concerned about the 'almost mushroomed' valve end and
adjustment screw. I'm going to replace the adjustment screw since its a
simple thing to do, but wondering what would cause this condition to occur
in the first place.
In the back of my mind, I wonder if the crack (and hairline fracture)
between the valves will get worse and make the head unusable and have to do
the job again (I'd prefer not to spend another $500 on a new head). Or, is
the almost-mushroomed valve going to cause a problem (or be a sign of
future impending doom)? I hadn't experienced any valve tapping in the past.
Given that this head gasket leaked, am I just avoiding the other side? (I
did notice this head leak was a 'seeping' leak whereas the other head is
bone dry.
Thoughts? Comments? Advice?
Gregg
90 Westy (BlueBerry)
|