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DISCUSSION => Engine + Driveline => Topic started by: juliea on November 17, 2010, 03:27:06 PM

Title: Which thermostat - 88 deg or 92?
Post by: juliea on November 17, 2010, 03:27:06 PM

Anyone have advice on which thermostat I should use? Looks like Pelican has two that work for m42's - an 88 deg and a 92 deg one. Is there a reason to go with one vs. the other?

Title: Which thermostat - 88 deg or 92?
Post by: DesktopDave on November 17, 2010, 05:03:43 PM

I went with the warmer one to improve fuel economy & help the motor last a bit longer.  It might work out, might not.  The lower temp one might help your motor make more power.  The difference between the two is pretty small though.

FYI, the aux fan switch in the radiator has a similar range for low and high speed.  If you use a hotter thermostat it might keep that aux fan on longer.  I ordered a matching part with my thermostat.

Title: Which thermostat - 88 deg or 92?
Post by: romeomike on November 27, 2010, 02:07:05 AM

Since I live in Vegas, I went with the stock choice (88C). I figure the lower temp makes it a bit easier on my cooling system.

Title: Which thermostat - 88 deg or 92?
Post by: cristimm on November 28, 2010, 02:28:56 AM

Quote from: DesktopDave;98760

I went with the warmer one to improve fuel economy & help the motor last a bit longer.  

I agree with the fuel economy part but why do you say that a higher temp thermostat will help the motor last longer?

Title: Which thermostat - 88 deg or 92?
Post by: DesktopDave on November 28, 2010, 09:59:29 AM

I don't have any real facts to back it up, just what I've heard 'round the campfire.  A lot of my buddies are diesel geeks, they love hot temps.

Warmer operating temps would improve a gas engine's lifespan similarly, but I'm not sure at what temp the motor would start to break.  I'd guess it's less than 92degC and also dependent on the type of driving the car does.

A majority of my driving is on the highway, that's where I heard a warmer motor does best.  I'd figure that if it was mostly rush hour or the 'burbs I'd go with a cooler thermostat to get the car up to temp as quickly as possible.

Title: Which thermostat - 88 deg or 92?
Post by: cristimm on November 29, 2010, 01:40:05 AM

I see. When I changed mine I got the 88c version (original was 92) because I do a lot of city driving. I've noticed that newer cars have higher and higher operating temperatures, for better emissions and fuel economy but IMO this is not good for the engine.