Vanagon EuroVan
Previous messageNext messagePrevious in topicNext in topicPrevious by same authorNext by same authorPrevious page (July 2011, week 3)Back to main VANAGON pageJoin or leave VANAGON (or change settings)ReplyPost a new messageSearchProportional fontNon-proportional font
Date:         Tue, 19 Jul 2011 10:22:35 -0500
Reply-To:     mcneely4@COX.NET
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         Dave Mcneely <mcneely4@COX.NET>
Subject:      Re: Watching Oil Temp (long, as usual)
Comments: To: Rocket J Squirrel <camping.elliott@GMAIL.COM>
In-Reply-To:  <1311087322.26578.91.camel@TheJackUbuntuNetbook>
Content-Type: text/plain; charset=utf-8

Mr. Squirrel, I believe that you have a tencentlife oil cooler installed as well. Is that correct? I would expect oil temperature to run closer to coolant temperature with the external cooler than without, under load or at high ambient temperatures. An engine oil temperature of 200 F seems reasonable to me. I would expect that without the cooler, it might be climbing to more like 220 or even higher. I assume you have the stock thermostat, rather than a slightly cooler one.

How does your oil pressure respond to the conditions you describe below? That is, does the oil pressure drop when you put the extra load on and the oil temperature increases above coolant temperature? If it drops, does it drop to a level that would be undesirable? When you are at load, and drop back to idle, what happens to oil pressure -- how low does it go?

Thanks, mcneely

---- Rocket J Squirrel <camping.elliott@GMAIL.COM> wrote: > I just completed the wiring to my swell new gauge cluster: oil pressure, > oil temp, ATF temp (okay, not yet hooked up), engine/cabin battery volts > (they are on separate charging systems so being an electrical geek I > like to be able to monitor them both), and tach). > > This will be the first time I've ever had a vehicle with an oil temp > gauge! > > So I'm watching the gauge to learn how oil temp responds to driving > conditions. Once the little thermostat thingy in the oil filter banjo > adapter's bypass opens up and oil starts being sent to the heat > exchanger, the gauge rises up to about 180-185F and pretty much stays > there under light town driving. The coolant temp gauge in the van's > instrument panel shows a steady temp, too. > > So last week I'm heading out of town on the highway, up a grade, into a > headwind, and pushing pretty hard. Excited to be going on a camping trip > to a new site. > > What I saw was that while coolant temp continued to stay constant, oil > temp went up -- 195, 200F. The engine's working harder, okay. But here > the coolant temp gauge says that the cooling system is keeping up with > the demand while the oil temp says otherwise. > > Obviously, then, the senders for the two temp gauges are seeing things > differently. > > So here's what I'm thinking, correct me if I'm wrong: > > Oil temp and coolant temp decouple under high engine demand, and that > while the cooling system is capable of keeping the portions of the > engine that the coolant is in intimate contact with cooled, the oil is > in contact with portions of the engine that the coolant doesn't reach > and which are close to the combustion action. > > So where is this? My first guess is the heads. The coolant surrounds the > jugs, but not the heads, which are part of the combustion chamber and > where oil flows over the hot valve stems. > > The oil temp gauge reports the temperature of hot oil returning from the > heads mixed with general overall engine oil temp, so therefore it's not > an accurate indication of peak oil temp. And that's why people install > CHT gauges, to get a better picture of what's going on in the heads. > > This is my initial interpretation of what I'm seeing. > > -- > Rocky J Squirrel (Jack Elliott) > '84 Westfalia: Mellow Yellow ("The Electrical Banana") > '74 Westrailia: (Ladybug Trailer company, San Juan Capistrano, Calif.) > Bend, OR > KG6RCR

-- David McNeely


Back to: Top of message | Previous page | Main VANAGON page

Please note - During the past 17 years of operation, several gigabytes of Vanagon mail messages have been archived. Searching the entire collection will take up to five minutes to complete. Please be patient!


Return to the archives @ gerry.vanagon.com


The vanagon mailing list archives are copyright (c) 1994-2011, and may not be reproduced without the express written permission of the list administrators. Posting messages to this mailing list grants a license to the mailing list administrators to reproduce the message in a compilation, either printed or electronic. All compilations will be not-for-profit, with any excess proceeds going to the Vanagon mailing list.

Any profits from list compilations go exclusively towards the management and operation of the Vanagon mailing list and vanagon mailing list web site.