Date:         Tue, 16 Jun 1998 23:12:33 -0400
Reply-To:     "Anthony L. Mourkas" <frankenstein@TELPLUS.NET>
Sender:       Vanagon Mailing List <Vanagon@vanagon.com>
From:         "Anthony L. Mourkas" <frankenstein@TELPLUS.NET>
Subject:      Too much timing advance
Comments: To: Vanagon Mailing List <Vanagon@VANAGON.COM>
Content-Type: text/plain; charset="US-ASCII"

After filling the gas tank at a different than usual gas station last
Thursday I noticed on the ensuing trip that the 1981 Vanagon (49 states
motor) was pinging when accelerating hard, at high revs, or under load.
I put it down to bad gas, but today I checked out the motor during a lull
in the monsoon season here in NE.  I found the timing advancing off the
scale!

The timing measured 7 degrees BTDC at 820rpm idle, but rose to 40 degrees
BTDC at 2,000rpm, and was 50+degrees BTDC at 3,000rpm.  Ouch!  Gulp!

My measurements:

           total adv     vacuum
           cent + vac    disconnected    specs*

 820rpm     7deg BTDC    7deg BTDC     7.5deg BTDC @  850rpm
2000rpm    38deg BTDC   26deg BTDC    9-14deg BTDC @ 1600rpm
3000rpm   >50deg BTDC   38deg BTDC   21-25deg BTDC @ 3400rpm

*as published on Old Volks Home website - Thanks!

What I read into the above is that my vacuum advance is functioning okay,
but the distributor's centrifugal advance curve is way out of whack,
advancing too far/fast.

So what is the cause and the solution?  Replace weak centrifugal advance
springs/weights/mechanism?  Replace/rebuild distributor?  Or???

By the way, many thanks to the list.  If I had not been monitoring recent
discussions here, I might not thought to check up on this.

Thanks,

Tony

Anthony L. Mourkas
Hampden, Maine, USA
1981 Vanagon Westfalia