Date: Sun, 12 Dec 2004 17:36:17 -0500
Reply-To: Dennis Haynes <dhaynes@OPTONLINE.NET>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Dennis Haynes <dhaynes@OPTONLINE.NET>
Subject: Re: 2.1L Engine: Oil Pressure Senders faulty reading
In-Reply-To: <42d2267e04121213591e459d00@mail.gmail.com>
Content-type: text/plain; charset=US-ASCII
Based on the description of the symptoms, you either have the incorrect
high pressure oil pressure switch, (very likely) or you have an oil
pressure problem. The high pressure switch is the one under the water
pump. It should be a .9 bar (12.7 psi) normally open (closes or
completes circuit with adequate pressure),switch. Many parts books and
incorrectly reading the ETKA will often list the 1.8 bar, (25.4 psi)
switch. The engine will not reliably produce this pressure @ the 2,200
rpm which is when he circuit board looks for that sensor to be closed.
Also, make sure the correct oil is being used and that the crankcase is
not overfilled. The oil level should be between the marks. As I've
stated in the past, the top mark is not the full mark. The top mark is
the maximum do not ever exceed not matter what mark! Hope this helps.
BTW, get the sensors from the dealer or get OEM. They are not expensive
and they work.
Dennis
-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf
Of Detroit Bus
Sent: Sunday, December 12, 2004 4:59 PM
To: vanagon@GERRY.VANAGON.COM
Subject: 2.1L Engine: Oil Pressure Senders faulty reading
Hello all. This is my first post to the list, I've been reading for
about a month.
My 87 Vanagon Weekender (recent new 2.1L engine, installed before i
purchased the vehicle) just had the circuit board behind the dash
replaced to get the oil pressure light and temperature gauge back in
working condition (the oil pressure light/buzzer was constantly on,
and the previous owner had simply unplugged the circuit board from the
back of the gauge panel-!!!!!-; the temp gauge was just dead).
My mechanic used an OEM, dealer-supplied circuit board ($$$). The temp
gauge is now operative, but the oil pressure warning system is still
faulty, but in a different way. I am confident that the engine oil
pressure is fine and that this is an electrical problem.
The mechanic (despite my great interest in doing my own work, I live
in NYC and have almost no resources to do my own maintenance) replaced
both oil senders with new units at the same time he replaced the dash
circuit board. He did not use dealer parts for the senders, but he
works exclusively on VW's (30 years) and has a lot of experience with
Vanagons so I trusted his judgment. He said he replaced the senders
because of some corrosion on my original senders, which for some
reason were not replaced during the installation of a new engine.
After picking up the Vanagon, and after about ten miles of driving,
the oil pressure light and buzzer tripped ON at about 2600 RPM, and
went OFF when the engine passed 3000 RPM. (Yes, I am confident that my
oil pressure is actually OK). As the engine warmed, this RPM band rose
to about 2800RPM - 4000 RPM (that is, the buzzer went turned off at
about 65 mph in 4th, 50 in 3rd, etc., and went back ON if the RPMs
dropped back down. A quick downshift to 3rd from 4th would cancel the
buzzer.) I assume the RPM band shifts up as engine pressure reacts to
the oil getting warmer. Driving around the city saw the buzzer going
on and off, but always within the above-mentioned RPM ranges. The
false readings do not begin until the engine has warmed up; that is, I
can run at RPM ranges from 2500 - 4000 RPM with no buzzer for about
ten minutes,and then the symphony begins. Since I've already melted
one engine (in my 77 Beetle) due to catastrophic oil pressure loss,
this problem is a bit irritating, to say the least.
Returning to my mechanic, I suggested that either he had (a) switched
the high and low pressure senders, (b) installed two of the same type,
or (c) one or both of the new senders was defective. He will take a
look tomorrow and probably end up ordering two OEM dealer senders
(probably should have done that in the first place...).
Are there any guesses or advice on which sender is bad, or anything
else that might be the problem?
Secondly, and on a different subject, the coolant level dropped 2" in
the expansion tank after the temp sender was switched out. Did this
procedure let air into the system, and will it self-bleed as long as I
keep up with the coolant?
thanks for reading all this,
--
Garrick, Queens, NYC
'87 GL Weekender (my first water-cooled!)
*****
With fond remembrances of:
'77 Beetle
'67 Bus
'59 Pickup sn# 460440
'67 Beetle
'76 Camper Bus
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