Date: Sun, 8 Jan 2012 23:19:20 -0500
Reply-To: Dennis Haynes <d23haynes57@HOTMAIL.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Dennis Haynes <d23haynes57@HOTMAIL.COM>
Subject: Re: temp gauge shenanagins
In-Reply-To: <1326080507.9450.YahooMailRC@web80005.mail.sp1.yahoo.com>
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Over the years I've dealt with my share of bad t-stats. They don't go
intermittent unless they are the wrong type. It is common for the wrong stat
to be sold for the Vanagon. The lower disc is in the wrong place and the
wrong diameter causing it to stick in the housing.
Note I said combustion gasses in the cooling system. That includes un burned
hydrocarbons from the head lifting under pressure or a cracked head. I have
seen cracked heads in the exhaust ports which can put coolant directly into
the exhaust and into a cylinder if the engine stops with that exhaust valve
open.
Dennis
-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of
Mike Miller
Sent: Sunday, January 08, 2012 10:42 PM
To: vanagon@GERRY.VANAGON.COM
Subject: Re: temp gauge shenanagins
I certainly hope it's neither a bad thermostat, which is new, nor exhaust in
the coolant, which is expensive.
Mike
________________________________
From: Dennis Haynes <d23haynes57@HOTMAIL.COM>
To: vanagon@GERRY.VANAGON.COM
Sent: Sun, January 8, 2012 5:57:45 PM
Subject: Re: temp gauge shenanagins
The temp gauge responds to the coolant that should be flowing through the
engine. The radiator fan is turned on by a switch in the radiator itself.
Having the engine overheat without the radiator getting hot enough to turn
on the fan is the symptoms of a bad thermostat or when intermittent
combustion gasses getting into the cooling system. These gases and/or a bad
pressure cap can cause coolant to blow out while driving and then be low for
the next cold start turning on the low coolant light until the coolant warms
and expands.
Dennis
-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of
Mike Miller
Sent: Sunday, January 08, 2012 6:11 PM
To: vanagon@GERRY.VANAGON.COM
Subject: Re: temp gauge shenanagins
Sorry for the late replies, I've been out and about.
The needle has done this before, swept over to high but no high speed fan
on, then later fall back to normal with nothing changing.
Now red light blinks all the time but the needle is behaving, for the time
being at least.
Mike
On Jan 8, 2012, at 9:32 AM, David Beierl wrote:
> At 12:02 AM 1/8/2012, Mike Miller wrote:
>> But...my temp gauge goes sl[e]wing up to the red zone and the light
>> blinks.
>
> Less common reason: short to ground in the temp sender wiring.
>
> More common reason: you have an old-style coolant-level controller as
> found in roughly pre-'85 vans, and it has triggered. Could be a bad
> controller (and anyway you'd rather have the newer, cube-shaped one
> which will cause the light to blink without visibly affecting the
> needle), but more likely it's an open in the wiring of the level
> sender (the plug comes to mind) or the sender itself which is just two
> s/s pins sticking down into the pressure bottle. Scrub the pins with
> ScotchBrite, check/clean the connector, make sure the ground is good.
> If you're running a very weak coolant mix that could conceivably cause
> this as well.
>
> Sight unseen my bet is on the connector at the pressure bottle.
>
> Yrs,
> d