Thermostat Questions

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Apr 23, 2009 | 01:55 PM

Texas Mad Man

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Thermostat Questions

I've got a 2000 e150 4.2. Thinking of changing the 195 thermostat for a 180? or 185? I assume those are available. Will there be any adverse issues if I go cooler?

Also, I've change several t-stats on Dodge vans, but never this one. Are there any things to watch out for?

As always thanks.

Apr 23, 2009 | 11:14 PM

YoGeorge

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From: Detroit

Quote:

Originally Posted by Texas Mad Man

I'd be concerned about engine etronics not running everything properly if the engine is running too cold. Dunno for sure if 180/185 would really make a diff but why do you want to change the thermostat? Cooling system should stay on top of keeping your engine temp steady with the stock temp 'stat.

George

Apr 24, 2009 | 10:56 AM

Texas Mad Man

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George:

Thanks for the reply. The reason I thought I might try a 180 degree t-stat is because my van runs between 210 & 215 with the 195 t-stat that's in it now. I've flushed the radiator and blown the bugs out of it and it still runs this high. Do you think if I drop to a 180, things will be closer to normal?

Thanks

Apr 24, 2009 | 11:40 AM

YoGeorge

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From: Detroit

Quote:

Originally Posted by Texas Mad Man

I don't know the specs on the Ford 195 degree stat. I believe that in general, a thermostat *begins* to open at its rated temp and is fully open maybe 10-15 degrees above that, so your 195 may be working as designed. I don't think 210-215 is a problem if you are running antifreeze in a pressurized system--it is quite far from boiling and may in fact be well within the "normal" range.

If the limitations of your cooling system are somewhere other than the thermostat (like a blocked radiator, etc), then running a 180 degree stat (or no stat at all) would not make a difference once everything is fully heated up. It would run cooler in the winter, say, but then you probably want the engine to be warmer to give you more heater output.

One thing you could do is put your existing stat in a pot of water with a thermometer in it, put it on the stove, and watch the stat when it gets up to 195 or so and above that. It's possible that your existing stat is not opening until the temp is above its rating(?)

Are you basing your 210-215 readings on the factory gauge (which is fake) or a real, external gauge?

George

Apr 24, 2009 | 01:43 PM

Texas Mad Man

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George:

Thanks again, I am basing my temp reading on what my scan guage is showing.

Below is a thread I started concerning my temp, and some thought 210-215 is too hot. This is why I thought I might go with a cooler themostat. I'm in north Texas and it gets hot here. We have already hit 100 degress this week.

https://www.ford-trucks.com/forums/8...s-too-hot.html

Apr 24, 2009 | 02:04 PM

YoGeorge

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From: Detroit

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Originally Posted by Texas Mad Man

If it runs at that temp at all ambient temperatures, that is probably what the thermostat is giving you--if it does not run appreciably hotter when the outside temp is 100 than it does when the outside temp is 25. Here, changing the thermostat would make a global difference. I would still stick with the factory spec stat, however; maybe find out what the best and most consistent brand is these days. Alternatively, the temp sender may be a bit out of calibration per the other thread. I don't think 210-215 is dangerous at all.

If you are running your cooling system at its limits (with the stat fully open), changing stats will not make a difference. In short, if this is your problem, a 180 stat will not make a difference for you when things get really hot, and this would be the scenario which would actually cause your engine to overheat--pushing the cooling system beyond its limits. But if this was the case, I'd expect to see your engine running a lot hotter at 100 ambient than at 25.

George

Apr 25, 2009 | 01:04 AM

pfogle

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Consider this. Every GM engine is rated for a 195 degree thermostat but runs at about 220 degrees in actuality. The hotter engine temps actual make the engine run more efficiently, you get a more complete burn of the fuel. 210 to 215 is no where close to too hot. If it was running at 240 I'd worry, but not in that range. You could go with a 180 t'stat but you would probably just see a decrease in fuel economy.