Cooler than cool

[Tom Kelly]

Like a lot of members, I have a 160 deg. thermostat in my 86. And with a new radiator and pump it generally keeps things at 160 almost all the time (heavy traffic on hot days being the exception when it occasionally hits 200)
I don't drive it much in the winter but when I do I noticed it can run as cold as 147. I am wondering how that is possible? Wouldn't the thermostat close at 160? I can see it getting a few degrees under set but 13 seems like a lot. Comments?

 

[turbo nasty]

Maybe your tstat isnt closing all the way. How old is it?

 

[Tom Kelly]

Maybe your tstat isnt closing all the way. How old is it?

No more than 3 years old

 

[Tom Kelly]

No more than 3 years old

Before I replaced thermostat I was wondering if this behavior was typical

 

[John Larkin]

I've never seen one run that cold. However running that cool is not all good. The car has a harder time burning fuel completely. I could not pass emissions with a 160 stat. I went to 180 and the car performs perfectly. You can end up with oil issues also due to abnormally low temps. Engines are designed to produce heat and a certain amount is needed for efficiency. You might rethink the change.

 

[Tom Kelly]

I've never seen one run that cold. However running that cool is not all good. The car has a harder time burning fuel completely. I could not pass emissions with a 160 stat. I went to 180 and the car performs perfectly. You can end up with oil issues also due to abnormally low temps. Engines are designed to produce heat and a certain amount is needed for efficiency. You might rethink the change.

The car came with this when I bought it. It seems to be a common part of the turbo tweak installation. I have been thinking of making the change and am trying to get the big picture of how that might relate to other mods already made. Thanks for reminding me.

 

[1986 Buick GX1]

Mine has run low 150's in October with the heat on (stock rad w/ 160• stat)
I assumed the heater was taking heat out of the block side of the thermostat so the engine didn't heat up, but l'm not for sure.

 

[Tom Kelly]

Mine has run low 150's in October with the heat on (stock rad w/ 160• stat)
I assumed the heater was taking heat out of the block side of the thermostat so the engine didn't heat up, but l'm not for sure.

 

[Tom Kelly]

I know the fan comes on at 160 (low speed) and switches to high at 180 or 190 I don’t remember. I don’t know if that’s original or a result of turbo tweak tuning. So if I change to 180 stat. The fan would be fighting the stat. Gotta dig deeper into this.

 

[~JM~]

Buy a new 160 T'stat from Kirban.
http://www.kirbanperformance.com/product/144/160-DEGREE+THERMOSTAT+#1508.html
Drill a small (1/8") hole through the T-stat disk & mount that at the 12 o'clock position. The hole will allow a small amount of flow & prevent an air pocket from being trapped.

You might as well pick up a new stainless steel T'stat housing at the same time. http://www.kirbanperformance.com/product/143/STAINLESS+THERMOSTAT+HOUSING+#6706.html

What do the coolant hoses & belts look like?
http://www.kirbanperformance.com/products/5/ENGINE,+FUEL+and+IGNITION+PARTS.html?cur_pos=180

 

[turbofrank]

Long ago when living in Michigan driving in winter with 160 T 140 -150 was norm unless driving 1hr or more than temp would reach 160. How are you reading temp gauge,SM,PL if gauge possibility it's off.

 

[Chuck Leeper]

Bypass hose.....Ambient low enuf, stat closed, heater on, the bypass circuit allows enuf coolant flow to stay below stat.

 

[~JM~]

Bypass hose.....Ambient low enuf, stat closed, heater on, the bypass circuit allows enuf coolant flow to stay below stat.

Forgot about that angle. Could the bypass be blocked off, or have a throttling valve installed to adjust the flow?

 

[Chuck Leeper]

Forgot about that angle. Could the bypass be blocked off, or have a throttling valve installed to adjust the flow?

I blocked it off in the pump.. Drill/tap. Used the intake port for the aftermkt gauge sender. Drilled 4 - 3/32" holes around the stat face. Done deal.

 

[salvageV6]

I wouldn't worry about it, I've seen it often in the 30 winters my cars have been through....

 

[Turbo Keith]

Test your T stat before you install it , I always do that .

 

[Tom Kelly]

Just to be sure I finally installed a new 160 degree thermostat (with Kirban's aluminum sleeve) No change. still ran cold. And then my aces at the Auto Center in Chappaqua suggested I compare the gauge with the reading on the scanmaster. DOH! Sure enough, according to the scanmaster, the t'stat is doing it's job right on. Gauge is different (always cooler) by 8-14 degrees. contacted tech support at speedhut about this and they say that the most common problem is that the secondary sensor location is often too close to fresh cold water and thus gives cooler readings than the primary sensor. Makes sense to me and now that I know, the difference is not a problem.

 

[Scarab]

check you gauge also, my scan master and gauge is about 20 degree's off from each other

 

[mikestertwo]

If you drive in cold weather you should be running a 180* thermostat period!

 

[Tom Kelly]

If you drive in cold weather you should be running a 180* thermostat period!

Yes, but I almost never drive it after December 1st until April. Just on those beautiful warm winter days to exercise it a bit. this winter, it will be vacationing at the paint and body shop getting a full makeover.