Date: Sat, 26 Jan 2008 08:03:56 -0500
Reply-To: Jeffrey Lubin <visionwizard@VERIZON.NET>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Jeffrey Lubin <visionwizard@VERIZON.NET>
Subject: Re: my first cooling system scare
In-Reply-To: <d81c42190801201714l108323bfu58f19d85b01abfa1@mail.gmail.com>
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I thought I'd follow up on my original post, for archive purposes, in
case someone else is searching with the same symptoms.
To recap the problem, in my '86 weekender (2.1L engine) I had a high
screeching noise that sounded like a v-belt slipping, and a slow loss of
coolant with no visible drops on the ground. The screech was especially
bad in cold weather, and when it went on for more than a few minutes,
the coolant temperature gauge would go up higher than usual. And one
other symptom I didn't mention in the original post: After some of this
screeching, I could detect a slight burning smell if I walked back to
the engine compartment.
I got a few replies with the very good suggestion that I check the water
pump. I did this, turning it by hand with the belt off, and it was
fine, as was the alternator. The belt itself was looking worn out, but
why? It had been replaced the same time as the other two, and they
looked fine.
Well, it turns out that there was a slow coolant leak from the driver's
side end of the short hose (N90128703) that connects the water pump to
the passenger's side of the crankcase. This location drips down onto an
exhaust pipe, and is very close to the bottom of the water pump /
alternator belt as well. So, coolant would either drip onto the hot
pipe, cause a burning smell (and not make it to the ground), or spray
onto the belt, causing it to slip. When the slipping got bad enough,
I'm guessing that it impeded the function of the water pump, causing the
temperature to go up.
BTW, I diagnosed the problem the morning after by attaching the cut end
of a cheap Wal-Mart bicycle pump to the nipple on the expansion tank
cap, and giving it a few quick pumps. Tell-tale drips ensued quickly.
Credit to Dennis Haynes who, as usual, guessed the problem correctly,
after learning that the water pump checked out okay.
Also, I'm now a big believer in spring-type hose clamps. This leak, and
another I found on the back end of the front heater core to coolant
distributor hose, were both from screw-type clamps.
-Jeff
John Meeks wrote:
> On Jan 20, 2008 6:52 PM, Jeffrey Lubin <visionwizard@verizon.net> wrote:
>
>> Another rite of passage, I guess.
>> This evening, after driving for about ten minutes in the bitter cold
>> here in NJ, my temperature gauge started going up pretty quickly, until
>> the red light started flickering. So I slowed down, and then, almost
>> immediately, it went back down to normal. I had a van-load of screaming
>> five-year-old girls inside (it was my daughter's fifth birthday), so I
>> couldn't hear whether then fan had turned on and/or off.
>> After I got home, from what I could tell in the dark, everything seemed
>> fine.
>> Any thoughts on what might have happened? I can't do any diagnosis
>> right now, but I'd appreciate guidance on how to proceed. Thermostat?
>> Only other symptom during this fateful voyage is that the alternator
>> belt, which has been squealing a bit on start-up, was squealing pretty
>> much the whole ride instead.
>> Thanks,
>> Jeff
>> '86 wolfsburg westfalia weekender
>>
>>
>
> Jeff,
>
> Loosen or remove the belt and check for wear. While the belt is
> loose/off try to rock the water pump pulley. If there's much movement,
> the bearings are worn and you will want to replace the pump. Loose
> pump bearings can seize under load and squeal the belt. This would
> raise your coolant temp.
>
> It's a good time to replace the belt unless it looks really good, but
> that squealing you heard was friction on the belt.
>
> Bitter cold can sure bring out weaknesses in mechanical systems.
>
> --
> John Meeks
>
> '91 Multivan, '85 GL bits
> Northern Michigan
> KC8ZFN
>
> Vanagon Rescue Squad
> http://www.vanagonauts.com/Vanagon_Rescue_Squad74.htm
>
>
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