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Old 05-08-2007, 02:38 PM   #10 (permalink)
TimMullen
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Join Date: Jun 2003
Location: Chantilly, VA
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Quote:
Originally Posted by neckstrap
The big question is, does the Lotus NEED the extra cooling? Engine oil should run at over 175 degrees F to lubricate property and evaporate any condensed water.
Lotus seems to think we need the coolers, or they wouldn't have added them. The Celica engine was known to have oiling problems - something that we don't seem to have with the coolers.

Quote:
Guys who build high performance engines for racing applications use a thermostatic valve to bypass external oil coolers until the oil has reached the proper temperature. Then, the valve diverts the oil trough the cooler as necessary to keep it under 230 Degrees. I don't find any thermostatic control on the lotus
You need to look harder. The "sandwich plate" that the oil lines connect to is the oil thermostat. Lotus does things the right way.

Quote:
Most of us would probably avoid a lot of leakage problems and have better lubrication and SAVE A LOT OF WEIGHT by removing the oil coolers and using the stock Toyota oil system.
Like I said above, the stock Toyota oil system seems to have a lot of oil related problems and failures. That's why we have the coolers.

Quote:
The proof would be if someone installed an oil temperature gauge on their Lotus and tried running with and without the oil coolers. Since mine is not even running yet, I can't try this. Any volunteers?
It's been done. The coolers do a great job and the oil runs at the proper temperature.

For what it's worth, a lot of cars have oil coolers. My '93 Honda Accord has one from the factory. My '94 Miata (and most of the others), and many of the Corvettes, etc. also have an oil cooler (although it's an oil/water heat exchanger) on the car from the factory. There is nothing exotic about an oil cooler.

The original batch of US Elises had a problem with some of them developing leaks. It was not a problem with the design, but with the installation of them - basically you need to wrenches to tighten the fitting, one to hold the cooler fitting in place, and the other to tighten the hose fitting. Apparently, someone at the factory wasn't using the one on the cooler, and it was leading to cracks in the tubing to the fitting. That process has been fixed.

We have had a couple of oil hoses leaking. That is a very low percentage. Low enough that it isn't really a major problem.
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Tim Mullen --- There is no such thing as Touring suspension or Touring wheels.

I love being married. It's so great to find that one person that you want to annoy for the rest of your life. - Rita Rudner


Chantilly, VA http://members.cox.net/elans4/
05 Lotus Elise - Chrome Orange - No Touring - No LSS - No Hardtop - Lotus Driving Lights - Lotus "Chin Guards" - plain and simple.
94 Miata R Package - Black
72 Lotus Elan Sprint - Colorado Orange/Cirrus White
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