Date: Sat, 1 Dec 2007 09:33:30 -0800
Reply-To: Michael Elliott <camping.elliott@GMAIL.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Michael Elliott <camping.elliott@GMAIL.COM>
Subject: New thermostat funky?
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A couple months ago I replaced the water pump -- it was making an ominous
grinding noise. Felt crappy when it was removed, too. Installed a new Temp
II sensor and thermostat at the same time. The thermostat came from one of
the usual online presences, can't recall exactly who but could find out if
it's relevant. The packing list noted that it was one that was set for 10
degree cooler than stock.
Indeed, with normal city driving at outside temps in the 70F range, the
temp gauge seems to rest just at the left edge of the LED whereas
previously it rode straight up, bisecting the lamp.
This morning I just returned from a two-night camping trip in the San
Diego mountains. It was 35F this morning and the first 2/3rds of the drive
are mostly downhill, a 6,000 ft elevation drop in about 60 miles. For most
of the downhill portion, the temp needle sat between the painted "box" at
the left-hand side of the meter face (this is a 1984 1.9L) and the left
edge of the LED, mostly closer to that painted box than the LED. In other
words, at about halfway between left (dead cold) and straight up.
The engine was so cool that the ECU went open-loop during long downhills
(auto transmission in "2," holding road speed down), as determined by the
Ken Lewis O2 monitor.
Once I got to the flats, in 55F temp, freeway speeds of 70 mph or so, the
needle rarely kissed the left edge of the LED.
This is new behavior, I'm not used to seeing the engine run that cool. I
know that a thermostat with a cooler set point may make it run cooler when
it's not being worked hard, but it should keep the engine warm. I can't
recall seeing the coolant that cold during downhills. That said, this was
the coldest weather I've made that run in. But still.
Next month I'll make the same trip, and it could be 20F cooler. I want to
be certain that the thermostat isn't, like, stuck open or anything.
--
Mike "Rocket J Squirrel" Elliott
71 Type 2: the Wonderbus
84 Westfalia: Mellow Yellow ("The Electrical Banana")
74 Utility Trailer. Ladybug Trailer, Inc., San Juan Capistrano
KG6RCR
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