Date: Fri, 4 Oct 2002 00:57:12 EDT
Reply-To: FrankGRUN@AOL.COM
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Frank Grunthaner <FrankGRUN@AOL.COM>
Subject: Re: More Cooling System/ now oil coolers/ more detail
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In a message dated 10/3/02 3:43:05 AM, kdlewis@juno.com writes:
<< I have been contemplating the installation of an oil cooler in my
230K mile+ crewcab. Especially after installing oil temp and pressure
gauges! The part I have not worked out in my mind is the need for the
oil-to-water heat exchanger if I do install the cooler. It seems to me
the plumbing sandwich adapter would fit perfectly in the place of this
exchanger. What are your thoughts? >>
Ken,
In the past, I did several measurements monitoring how fast the coolant
temperature came up to operational levels and how quickly the oil temperature
exceeded 180 F. In each case, I used the same course from my home to the
freeway, and then cruised the freeway in 4th at 40 mph. Typically in the
early morning on Saturday on my way to my Junkyard Constitutional. I don't
have the numbers in front of me but it was incontestable that both liquids
warmed up significantly faster with liquid/liquid heat exchanger. I was also
surprised at how effective the cooler was for reducing oil temperatures. Good
for more than 35 degrees F as I recall.
In my current setup, I use a thermostat takeoff plate to hold the
liquid/liquid exchanger in place. The details are all in the archives, but I
run the hot oil into the Mazda remote then to the remote oil filter and back
to the block. Steel reinforced 3/4 inch ID oil lines. I also have always used
the Volvo 760 TD oil filter as it is the very largest I could find. I think
some of my engine compartment pictures are on Alistair Bell's site and the
remote oil filter system should be readily seen. BTW, the Mazda RX-7 external
oil cooler has a thermostatic bypass circuit so I don't use one on the
takeoff plate. Works like a charm.
For the Audi turbo 3A project, I've worked up an even better system. It turns
out that the 5000T (turbo) has impressed me with its engineering for some
time. Not as amazing as the 944T, but close enough. Anyway, the early 5000T
had an oil filter adapter and external oil cooler assembly that I liked. It
uses two oil filters (2), and has the integrated oil temperature thermostat
and pressure bypass that is part of VW's Euro GTi package with external oil
cooler. Anyway, I've built an interface to the Audi 3A oil filter bracket
(same as the Fox, Quantum, Audi 4000 8V filter mounts) (it will work for the
G/J version too) that mounts the Audi oil filter/external cooler adapter. It
includes a liquid to liquid cooler for each oil filter. Looks so complex, no
Jiffy Lube dude will be able to think of doing anything except trying to add
gas to the oil filler tube!. Anyway, I am mounting two stock Audi 5000T
external oil coolers in the passenger side area behind the tire. All
explained in the archives, as is the mini sump for the turbo, the scavenger
pump to circulate the oil from the turbo to its oil cooler and back to the
crankcase. I also detail in the archives the low pressure vacuum pump I am
using to evacuate the crankcase for less aeration.
In a few weeks, I hope to have the tests done on the baffling chambers I've
designed for the diesel oil pan to complement the windage tray. All of these
issues contribute to effective thermal management and hopefully engine
longevity. Now, if only something could be done about the transmission!
So, blither, I think the liquid/liquid exchanger/cooler should be kept but
supplemented by the external unit (thermal fan control also).
Frank Grunthaner
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