Date:         Tue, 8 Feb 2000 08:01:20 -0600
Reply-To:     John Rodgers <inua@HIWAAY.NET>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         John Rodgers <inua@HIWAAY.NET>
Subject:      On The Road Again w/Oil Pressure Light Working
Content-Type: text/plain; charset=us-ascii

After just having gone the round with having the red oil pressure light
come on, after installing a new engine, just thought I would share more
details.

The engine was installed, break-in oil was added to the probler level,
and the engine started. After an appropriate run in and test drive, I
took the van towards home. Halfway there the oil pressure light flicked
on. This starled me and worried me. Instinct said panic, and stop, logic
said this is not mechanical, but electrical...no noises from the engine
but normal operating sounds. I continued, and noted that at idle the red
light was out, as rpm approached 2000 the light came on. This was on
Saturday.

Monday I called my mechanic. He said don't start the engine. He will
come and check it out. If the oil is in fact circulating, I can drive it
to the garage for further checkout.

All was well so far as the oil pressure was concerned. But the warning
light was definitely having a problem. Over 2000 rpm there was the
blinking oil light. Then as I drove up the road suddenly there was
suddenly this horrendous, loud buzzing sound. Startled me. Stopped the
van, soon as I did the buzzing went off. Was totally puzzled. NEVER
heard that before. Couldn't tell where it was coming from except under
the instrument cluster somewhere.

With the buzzing stopped, but the red light flashing I drove to the
shop. No problems.

Took a look underneath. AhHa!! The wire to the .3bar pressure switch
located on the driver side of the engine, between the pushrod housings,
was simply not connected. Hooked it up. Problem solved, right!!!
Wrong!!!!

Went for a test drive with wire hooked up, and everything seamed great.
Got back to one block from the shop and the warning light came on and
the buzzer went off. It was time for some serious trouble shooting.

Got out the old Bentley and went throught the trouble shooting check
list. The series of tests on the list went down the trail to to the
.9Bar (high pressure) switch at the rear of the engine under the
pulleys. The last check said repair/replace switch. Did that, no more
problems.

The low pressure switch is normally closed, completing the circut to the
warning light. When the ignition switch is turned on, energizing the
circuit, but the engine is not started, the light comes on and flashes.
When the engine starts, pressue at the switch opens the connection and
shuts off the light, thereby indicating proper oil pressure.

The high pressure switch is normally open, therefore there is no power
to the light or the buzzer. If a high pressure condition comes to exist,
such as a stuck oil check valve, etc, which could blow the seal at the
oil filter or elsewhere, the high pressure closes the switch completing
the circuit to the warning light and the warning buzzer, and the light
comes on and the buzzer sounds.

My suggestion to anyone buying a rebuilt/overhauled engine, is that if
you are getting one exchanged, specify in your order that new pressure
switches are part of thedeal and that they be installed before shipment.

John Rodgers
"88GL Driver