Date: Fri, 3 Jun 2011 22:46:42 -0500
Reply-To: Tom Hargrave <thargrav@HIWAAY.NET>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Tom Hargrave <thargrav@HIWAAY.NET>
Subject: Re: Thermostats [Was: Spooked!]
In-Reply-To: <1307157137.18233.153.camel@TheJackUbuntuNetbook>
Content-Type: text/plain; charset="utf-8"
I'm the first to admit that I don't know everything but there are a lot of "wives tales" floating around amongst mechanics.....
The thermostat does not pop open instantly at its rated temperature, it opens slowly and is fully open by the time it reaches its rated temperature. This means a lower temperature thermostat opens at even a lower temperature. This causes the engine to warm up slower which causes increased fuel consumption while warming up and increased gasoline wash down.
I'm sure you have read or heard that most engine wear occurs during the first 15 minutes after it's started? This is mostly due to gasoline wash down. The gasoline vapors condense on the cold intake manifold runners and cylinder walls, diluting the cylinder wall oil coating and degrading the oil's ability to properly lubricate the cylinder walls. The result is very high cylinder wall wear until the engine reaches a high enough temperature to stop condensing (it's warmed up).
This is also why engines need a choke or alternate means to make the fuel richer while warming up. The fuel system has to make up for the gas that condenses onto the insides of the intake manifold and cylinder walls!
Thanks, Tom Hargrave
www.stir-plate.com
www.towercooler.com
www.kegkits.com
-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of Rocket J Squirrel
Sent: Friday, June 03, 2011 10:12 PM
To: vanagon@gerry.vanagon.com
Subject: Thermostats [Was: Spooked!]
On Fri, 2011-06-03 at 20:59 -0500, Tom Hargrave wrote:
> A cooler thermostat is a quick fix for a lot of ails but it rarely solves
> anything.
>
> A lower temperature thermostat will open sooner causing the engine to run
> cooler & consume more gas. It will also cause the engine to wear out faster,
> again because it's running cooler.
Okay, so this brings up something I'm wondering about.
A while back, after replacing the thermostat in my 1984 1.9L, I was
surprised to see that the temp gauge was reading to the left of the
lamp, not centered on it, as I was accustomed to.
I asked the vendor (Bus Depot? Van Again? -- don't recall) what kind of
thermostat they sent, and they said they sent the lower temperature 80C
one, instead of the 87C one. As a favor.
I really didn't want to take the darn water pump out to replace the
thing so I've had it in there since.
I asked Steve, of Steve's Place, here in Bend, Ore., what he thought and
he said, "the higher temp one was to pass emissions in California. The
engine will last longer with the lower temp one."
Well, I didn't know so I set that matter aside.
Earlier this year, I took the van to Gary Young, of Young's Ole Volks
Home (also Bend, Ore.) and asked him the same question. "Lower temp one
is better for the engine," he said.
Gary has a decent reputation as a mechanic.
So, while camping this week, I'm cleaning out the parts bin and find two
thermostats: an 80C one, and an 87C one. Causing me to wonder about this
subject once again. Set them aside to trigger a post to this group.
Into your lap I toss this.
Sign me as "puzzled," someone who does not know who to believe.
--
Rocky J Squirrel
-----
No virus found in this message.
Checked by AVG - www.avg.com
Version: 10.0.1382 / Virus Database: 1511/3679 - Release Date: 06/03/11
