Date:         Fri, 16 Aug 2002 21:14:09 -0700
Reply-To:     Tobin Copley <tobin.copley@UBC.CA>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         Tobin Copley <tobin.copley@UBC.CA>
Subject:      Help needed troubleshooting VDO oil pressure gauge
Content-Type: text/plain; charset=US-ASCII; format=flowed

Hi all,

The scare I had last week with the bus developing a bad-sounding
knock turned out to be a loose muffler.  I'da thought she'd have
checked that before calling me on the cell phone, but I guess
she's be driving our completely trouble-free H*nda for too
long.  (And she used to be *so good* at roadside repair!).
Turned out to be a silly thing, but it's hard to fix cars over a
cell phone, and it turned out to be the kind of mistake /
surprise I'm happy to have!

Anyhow, the scare impressed upon me that I have to get on to
getting my oil pressure gauge working. What i have bought and
installed is a VDO 0-80 lb dual-terminal sender and a guage.

The problem:

1) The gauge goes to max pressure as soon as power is applied,
even with engine off.

2) To eliminate bad wiring from the equation, I tried a temp
set-up with the gauge right by the engine, with new sender wire,
power straight from the battery, ground straight to the battery
ground strap.  Gauge still goes to max pressure.

3) If I remove the sender wire from the terminal on the sender
and *ground* the sender wire, then apply power to the gauge, the
gauge needle moves smoothly up to zero and stays there.

I think the gauge part of the sender is bad (although the idiot
light part appears to be working properly) and therefore the
sending unit should be replaced.  Specifically, I think the
gauge part of the sender is stuck in an open circuit condition.
But my electrical knowledge is pretty much limited to a firm
grasp of the magic smoke theory, so what do I know?

So, list people: thoughts on where the trouble lies?  Agree /
disagree with my diagnosis?  Any help appreciated.  I'd really
like to get a gauge working in this thing.  (I replaced the main
and connecting rod bearings 700 miles ago, and would like to get
a heads up if things are going bad again).

Thanks,

T.

------------------------------------------------------------------------
Tobin Copley        Bowen Island, BC, Canada      49deg 23'N-123deg 19'W

'82 Westfalia 1.6L NA diesel ("Stinky")
'97 son Russell                                  =============
'99 daughter Margaret                           /_| |_L| |__|:| clatter
                             SPEED KILLS!       {.            .| clatter!
                        Drive a Vanagon diesel   ~-()-==----()-~