Date: Fri, 10 Aug 2001 21:01:17 -0400
Reply-To: Dennis Haynes <dhaynes@OPTONLINE.NET>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Dennis Haynes <dhaynes@OPTONLINE.NET>
Subject: Re: Spark Plug Failure
In-Reply-To: <a5.19b1a2d7.28a5123c@aol.com>
Content-type: multipart/alternative;
Broken insulators are caused by excessive heat or pre-ignition, ping. These
conditions can be caused by over advanced timing, lean fuel mixture, or
excess carbon causing increased compression. Unbalanced/worn injectors or
small vacuum leaks can cause some cylinders to run lean. In addition to the
compression check, do a leak down test. better indication of actual
condition. Check injector seals and manifold boots. Carbon build up on
intake valves can also cause mixture imbalance.
Good luck,
Dennis
-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com]On Behalf Of
Frank Condelli
Sent: Friday, August 10, 2001 6:32 AM
To: vanagon@GERRY.VANAGON.COM
Subject: Spark Plug Failure
Here is an item for everyones interest. My '87 Westy has been
running
crappy for the last few days and seemed to be getting worse. Backfiring
through the exhaust had me thinking burnt valve. Yesterday I took the
time
to start digging and find out what was going on. Looked first at the
distributor cap to find it full of dirt and the carbon seized up in its
hole.
Cleaned the cap, rotor and inners, then stretched the carbon spring and
put
the cap back in place and started up the engine. Seemed better but still
popping through the exhaust.
Removed spark plugs to have a look see and found plugs at # 2 and #
3
cylinders had cracked and missing porcelain. What's that all about ? The
colour of the plugs were good and these plugs Bosch WR7DTC's were put in
22,400 km ago ! STRANGE ! Anyways, I took a compression reading while I
had
the plugs out and found #1 - 125 lbs, #2 - 140 lbs, #3 - 120 lbs, #4 - 135
lbs. Not perfect but acceptable for an engine with 350,000 km on the
clock
and original engine. Put new Bosch WR7DTC's in and stated up the engine
and
VOILA ! Running great again !
Found my oxy sensor not working in the process so unpluged it
and
the engine seems to run fine with it unplugged. But, stumbles at idle with
it
plugged in. Will order up a new one. The one that's in there now is the
generic one from The Bus Depot put in 47,003 km ago.
Cheers
Frank Condelli
Almonte, Ontario, Canada
BusFusion a VW Camper event in Almonte, June 7-10
'87 Westy & Lionel Trains
Member: Vanagon List, LiMBO, IWCCC & Capital City VW Club
Vanagon/Vanagon Westfalia Service in the Ottawa Valley
STEBRO/Vanagon Stainless Steel Mufflers
Frank Condelli & Associates or http://frankcondelli.com
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