Date: Fri, 21 Jul 2006 14:15:31 -0400
Reply-To: dhaynes@OPTONLINE.NET
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Dennis Haynes <dhaynes@OPTONLINE.NET>
Subject: Re: Radiator fan debacle (86 Vanagon)
In-Reply-To: <00fa01c6ace0$90e1b280$650fa8c0@DELL>
Content-type: text/plain; charset=us-ascii
The real issue here is operator training and awareness.
1) The Vanagon is not really designed to have the engine idling for extended periods. Especially to support AC. Remember the AC is an after thought to begin with. Engine cooling is also compromised due to low water pump speed.
2) Not realizing the fan was not working is both aproblem for the AC and it Doesn't help the engine.
3) Extended idling operation of the AC in an 87 or later would evenutally put fan into high speed. At idle, this will eventually result in a discharged battery as alternator output does not keep up with all those fan loads.
4) Leaving the AC even after a failure? Does the fan provide any more air than open windows?
5) Not monitoring or knowing the imapct of water pump/alternator belt failure.
It should be noted that the low pressure cut out switches do not complelty protect the system. They are located on the high side of the system. Once the compressor turns on, as long as ~25 psi is maintained, the compressor will keep running. Not a difficult task except for a massive hose failure. This first missing link in the 86 and earlier systems is high speed fan operation and then compressor cut out if that does not
do the job. Also note on the later systems, the compressor will cut out if the radiator fan switch calls for high speed.
Dennis
----- Original Message -----
From: Kenneth Wilford <kenwilfy@COMCAST.NET>
Date: Friday, July 21, 2006 12:13 pm
Subject: Radiator fan debacle (86 Vanagon)
> Had a recent comedy of errors I wanted to share with the list. 86
> Westyrunning excellent went out on a 800 mile trip. I just took
> this van to
> Georgia and back a little over a month ago with no issues. In
> Maine the
> customer calls me to say that "steam" was coming out of the front
> of the
> van. I asked if her A/C was still working and she confirmed that
> it was
> not. She was sitting idling when this happened. The van was not
> overheating and there was no coolant on the ground under the van.
> I figured
> that the van had blown an A/C hose. An inconvenience in the heat
> but not a
> show stopper. I told the lady to take it easy and just drive back
> in the
> mornings and evenings when the weather wasn't too hot. She
> agreed.
>
> She got to Boston area when the next level of naughtiness
> occurred. She was
> driving down the road when someone behind her started honking.
> She looked
> down to see the overheat light on and also Alt light. Here is what
> happened: She kept the A/C on even though it was not putting out
> cold, the
> fans still worked and she was using them to keep cool. On the
> older A/C
> systems there is no pressure switch to kick out the compressor
> when the
> refrigerant is too low. Anything 86 and older is like this. So the
> compressor kept turning those whole time from Maine to Boston
> while the oil
> was being forced out the blown hose. This cause the compressor to
> lock up
> and this flung the A/C belt off which also caused the
> alternator/water pump
> belt to fly off as well.
>
> We had the van towed back and here is the kicker. The cause of
> the whole
> debacle was the radiator fan resistor. Apparently when she was
> idling, the
> resistor went out for the lower fan speed. This killed the
> radiator fan
> which caused the A/C pressure to rise too high and blow the hose,
> whichcaused the oil to leak out, which caused the compressor to
> lock up, which
> caused the belts to come off, which caused the van to overheat and
> now we
> might be looking at a cracked head. What a neat domino effect :-(
> This
> would not happen in an 87 or newer van because the compressor
> would never
> stay on when the refrigerant pressure is low. Only in the earlier
> version.Also it probably wouldn't happen in the 84-85 Vanagons
> either as their fan
> speeds don't have the achilles heel of the radiator fan resistor.
> It could
> probably only happen in 86 Vanagons. Again this van left here
> with the low
> speed fan, but with no warning the resistor can fail. The only
> warning sign
> is to visually look at it. If the green coating is flaking off,
> it is on
> the way out. However how many of us pull our driver's side headlight
> assembly off to look at this beast? No one of course. I just
> thought I
> would share this comedy of errors in case someone runs into this
> in the
> future. You are not alone!
>
> Thanks,
> Ken Wilford
> John 3:16
> http://www.vanagain.com
> http://www.strictlyvwauctions.com
> http://www.eurovan.org
> http://www.vwcabrio.org
> Phone: (856)-327-4936
> Fax: (856)-327-2242
>
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