2000 Blazer Thermostat

bhesson · #1 04-09-2007, 12:32 PM

Just wondering what you all may recommend. A 195 degree stock replacement or a 180 degree? I've always thought it ran a little hot in the summer so I was wondering if going to a 180 would help any. It's a 4WD 4DR LT and I do no towing.

Thanks for any comments ...

MT-2500 · #2 04-09-2007, 01:23 PM

180 will not help on running hot.
If you want your engine to live to a ripe old age use a 195 thermo in it.
A 180 will not warm up engine to burn off moisture and condensation and will sludge up the engine.
What is your actual running tempt in summer with air on and air off?
MT

bhesson · #3 04-09-2007, 01:30 PM

It varies in the summer but on very hot days at an extended idle of 2 minutes or more I see it reaching 220-230 with the air on but generally around 200-210, air on or off. I have a suspicion that the fan clutch may be bad too.

Anyway, in two weeks I'm replacing the radiator, cap, fan clutch, both hoses and the thermostat. The radiator has a small leak in the plastic tank at the top. I'm buying a Heavy Duty 70" Hayden clutch, a Stant 16 lb cap and Goodyear molded hoses.

Stant had two caps listed part# 11230 and 10230. I chose the more expensive 10230 but it looks like the exact same cap ?? Any idea which would be best. Neither has the pressure lever and both are 16lb?

Is there any advantage going to the larger 70" heavy duty fan clutch or would the standard size be fine?

The radiator is an after market replacement with a two year guarantee. I'm probably going to trade it in next Spring so that should be fine.

Thanks for your reply. I'll just go with the 195 degree. Any other suggestions are appreciated

ericn1300 · #4 04-09-2007, 07:32 PM

Good choices in parts, glad to see the radiator cap included as it's often overlooked. just be sure to get vin "Z" or "W" parts according to your vin number, it will make a difference on hoses.

depending on the cost of the fan clutch this might be good time to look at aftermarket electric fans. I've even seen a post on here that demonstrates how to use a Ford Taurus fan from the salvage yard as an electric fan replacment. electric fans will get rid of some of the "roaring" noises associated with the mechanical fan. do a search in this forum.

bhesson · #5 04-09-2007, 07:38 PM

Thanks for the reply. My vin is 1GNDT13W4YE .... I assume I have the "W" vin? That's the only "W" in the vin and there's no "Z"?

As far as the fan clutch, I'm just going with the standard heavy duty clutch but thanks for the advice. I'm looking at trading it in next spring. 150K is all I'd expect from it. I bought it with 36K ....

MT-2500 · #6 04-09-2007, 09:18 PM

Another cooling tip is to keep the rad and ac condenser fins clean and a good fan shroud.
Wash and blow them out.
After the engine tempt goes over 195 a 185 or a 195 stat cool the same.
Good luck
MT

vtmecheng · #7 04-10-2007, 12:12 PM

Stick with the 195 deg, in addition the what has been said your truck's emissions system uses the truck's engine temp as one of its inputs. You may have a problem with emissions testing, not saying you will but there is a chance. Also, go with the heavy duty fan clutch as it will help with cooling when sitting in traffic or at a light on those hot summer days when the AC is cranked.

bhesson · #8 04-19-2007, 06:39 PM

Everything went well and the radiator, hoses, thermostat, fan clutch and cap have been replaced. Immediately I noticed it now runs consistently around 195 degrees which is good.

My question is this. Prior to these repairs if the outside temperature was 55 or under it quite often ran at 160-180 degrees. Now it seems to run at 195 regardless of the outside temp. Does that mean I had thermostat problems prior to this? With the chance of sounding dumb, could that have also been related to my poor fuel usage problems? I've kept it well maintained in all areas but I only get 14-17 highway, if that, prior to the repairs. I just got it back today so I'm not sure what the MPG is now or if it has gotten better.

Thanks for any comments in advance ....

MT-2500 · #9 04-19-2007, 06:49 PM

Quote:

Originally Posted by bhesson

Everything went well and the radiator, hoses, thermostat, fan clutch and cap have been replaced. Immediately I noticed it now runs consistently around 195 degrees which is good.

My question is this. Prior to these repairs if the outside temperature was 55 or under it quite often ran at 160-180 degrees. Now it seems to run at 195 regardless of the outside temp. Does that mean I had thermostat problems prior to this? With the chance of sounding dumb, could that have also been related to my poor fuel usage problems? I've kept it well maintained in all areas but I only get 14-17 highway, if that, prior to the repairs. I just got it back today so I'm not sure what the MPG is now or if it has gotten better.

Thanks for any comments in advance ....

Yes to all
A bad thermostat can make the engine run cool and is engine is not up to 195 tempt the engine will run richer on fuel mix.
The good thermostat should help bring MPG back to normal or what it used to get.
When did you gas mileage go to bad or has it always been low.?

bhesson · #10 04-19-2007, 06:53 PM

My best guess is it went south starting last spring and last summer is when I first noticed it running hot with the air on and the outside temperature high. I'll see what it gets now since the repairs. Thanks for your reply, I appreciate it ...

MT-2500 · #11 04-19-2007, 07:07 PM

Quote:

Originally Posted by bhesson

My best guess is it went south starting last spring and last summer is when I first noticed it running hot with the air on and the outside temperature high. I'll see what it gets now since the repairs. Thanks for your reply, I appreciate it ...

Thanks for letting us know how it went.
If gas mileage does not come back to normal you might go for a tune up.
Good luck.
MT

bhesson · #12 04-19-2007, 07:11 PM

ok thanks.

bhesson · #13 04-21-2007, 10:49 AM

Well after the first fill up today, it looks like the fuel mileage is back to where it should be around 18-21 mpg ... I wish I'd noticed the low running temperature in cooler weather sooner and put two and two together considering the price of fuel now a days.

I've got 128K on it and I'll be trading it in next spring for I think a Chevy Tahoe. I should be good til then with the cooling system replacements, new fuel pump this past winter and a full tune up of plugs, wires, cap and rotor when the pump was replaced. The torque convertor clutches are slipping for a short period at 35 mph after extended highway driving but it's been doing that for 2 years and I can live with it and hopefully get through til next spring.

I've run the usual Blazer gambit with this 2000 Blazer bought at 36K. Replaced both front hubs at 70K, fuel pump around 121K, etc ... but it's been a pretty good vehicle to own. It was my first Blazer. Thanks for all the help ...

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