Temp question

[bgscott]

Hey guys I am a newbie with a partially refinished stock 90 gw. I will post pictures when I figure out how but I just got the air conditioning working today and naturally the engine temp, which I have never seen above 200 started inching up to two twenty at red lights. When I got up to speed it would cool back to 185 or so. So I purchased a new 192 degree thermostat and drove to the local radiator shop for a good flushing. He installed the new rthermostat when he was through. When I picked it up it now runs at a nice steady 215!!! It will slip up to 220 with the air on and at idle but doesn't seem to go higher. My question is what the heck happened? Did I have some thermostat that opened at lower temps? Did the radiator flushing clog some artery in the system? What should I expect from a stock 360 with a bunch of miles as far as temp on a hot alabammy summer day? I have a new fan clutch on here also.
By the way, I know nothing about auto mechanics but I am an old engineer with 30 years industrial maintenance experience. The young guys at work are educating me pretty well on this thing but it's nice to have a deep well of hands on knowledge to turn to!!

[Dr. Marneaus]

my original engine ran at about 210 when it was under normal conditions, and it ran perfectly fine at that point.

If you installed a 192 (which is close to stock) thermostat, I'd think a temp around 210ish is normal.

[svining]

These motors were designed to run a little hotter, at 193 degrees. Better carb function etc. Not sure if they suceeded on better milage

Originally Posted by Dr. Marneaus

my original engine ran at about 210 when it was under normal conditions, and it ran perfectly fine at that point.

If you installed a 192 (which is close to stock) thermostat, I'd think a temp around 210ish is normal.

[bgscott]

You guys think there is any reason to put a 180 degree thermostat back in it?

[the original Honcho]

As soon as i have a day off im going to put a 160 back in The Green Bastard like the PO had. It was overheating so i put a new 195*(its what the book called for) in it along with an older, smaller radiator that doesnt leak. I bought 2 Wagoneers from the same guy and the '91 RARELY peeks out of the blue area on the factory temp gauge- pretty sure it has a 160 also.

I would definitely drop back to a 180 or even a 160.

[Dr. Marneaus]

my experience is as follows:

A thermostat opens and closes based on a certain temperature, either increasing or decreasing the flow of fluid from the block into the radiator.

If you have a cooling system that has the capacity to cool to 160 degrees, but have a 193* t-stat, it's going to run at 193 or more, right? Simply because the t-stat will allow minimal flow at ant temperature under that.

If you have an old worn out cooling system that cannot cool the vehicle more than 193, i doubt changing the t-stat will do anything, because that doesnt affect the actual cooling capacity of the system, just how much its ALLOWED to cool. right?

My rig used to run at a solid 210. stock t-state stock radiator. Thats fine. I seen it climb to 235 once when it was 114* outside and i was pushing uphill trying to do 60. I backed it down to 40mph and it came back down to around 215*

I installed an aluminum radiator when my original one decided to spring a leak. When I did that, i put in a 180* t-stat simply because out here stuff doesnt really need to warm up. It never gets below freezing but once or four times a year.

My truck now runs at 185-190 in the cool weather, and never even touches 200* 9 months out of the year. In the summer, blazing hot on the highway it still runs at 190-195 unless im pushing up hill then it just about hits 200-205*. This past weekend was the first time in 1.5 years since installing the rad that it peaked 205*. I had it u pto about 215, in 4wd, going up hill through deep gravel, at like 10mph, for like 3 miles.

I attribute this to installing a better radiator and then installing a lower temp t-stat because it allows the better radiator to operate at its full capacity.

thats my take on it. If your rig is stock and your cooling system is old/stock a lower t-stat likely wont do a whole lot, and could even mess with the way the carb runs if it's stock and is still hooked up to all that stuff.

[bgscott]

I am in bama and we don't have to go thru emissions test. That stuff is long gone. Since my wag was running at 195 before I changed to the new thermostat I am not sure I can resist changing it to see if the running temp goes back down. I am sure it's fine at the current temp but if I don't try changing it the thought will be stuck in my head forever. I do think a nice aluminum radiator is in my future, or at least a new stock one. Where did you get yours?

[Rich88]

Originally Posted by bgscott

I am in bama and we don't have to go thru emissions test. That stuff is long gone. Since my wag was running at 195 before I changed to the new thermostat I am not sure I can resist changing it to see if the running temp goes back down. I am sure it's fine at the current temp but if I don't try changing it the thought will be stuck in my head forever. I do think a nice aluminum radiator is in my future, or at least a new stock one. Where did you get yours?

With AC now working its normal for temps to be a bit higher, especially at idle.

You didn't say if you had a fan shroud installed. If not, you need one.
FYI, the t'stat rating is not what the coolant temp will be. It will always be a little higher in reality. Our 360's are supposed to have 195* t'stats.

Back flushing a radiator is good, but does not guarantee to restore it to factory specs. In fact, if you have a new fan clutch and a shroud, I'd say the flush didn't do the job. A new OEM replacement will do you just fine, no need to waste bucks on "upgrades" unless you can happily afford the "cool" factor, no pun intended.

[bgscott]

Yes I do have a shroud. Anybody got a suggestion on where to get a good price on a radiator? I can look down through the coolant and see a lot of buildup in the top of the tubes.

[the original Honcho]

My '75 sat for a few years and I used Prestolite flush from O'Reallys and after the radiator looked like new! i also bought the flush system from Prestolite and it made the job easy!

[Rich88]

Originally Posted by bgscott

Yes I do have a shroud. Anybody got a suggestion on where to get a good price on a radiator? I can look down through the coolant and see a lot of buildup in the top of the tubes.

Take your pick:


http://www.bjsoffroad.com/prod-419.htm

http://shop.advanceautoparts.com/web...RPCOOLAMS_____

http://www.oreillyauto.com/site/c/se...yword=radiator

[Dr. Marneaus]

i picked up a Chinese aluminum one on ebay, but apparently they are no longer available for the old wags like mine.