thermostat and temp.....

[Red Baron]

I changed out my thermostat (it gave out) to a medium temp. one....would using the medium temp. thermostat cause the needle to read higher than when a high temp. thermostat is used? Thanx thumb for the help.

 

[SHOZ123]

If your high temp t-stat was weak and not maintaining it's rated temp then yes.

Other wise a 192F t-stat will obviously read higher than the 180F t-stat.

 

[Red Baron]

SHOZ123:
If your high temp t-stat was weak and not maintaining it's rated temp then yes.

Other wise a 192F t-stat will obviously read higher than the 180F t-stat.

The t-stat that was in the car was a 192F and it gave out, so I changed it to a 180F t-stat...but now the needle hovers higher on the gauge than with the 192F...is it causing the engine to run hotter? It's an Autozone t-stat that I put in...

 

[sdpatt]

Do you have any method to measure the actual temperature of the coolant at the thermostat ******? Until you know the real temperature, you are asking for an answer to an unknown question.

 

[Red Baron]

sdpatt:
Do you have any method to measure the actual temperature of the coolant at the thermostat ******? Until you know the real temperature, you are asking for an answer to an unknown question.

No....but the needle position is higher on the gauge with this t-stat than with the 192F...I know that as long as the needle is within the "normal" range, it's...well, normal...I'm just curious cause it's different now...

 

[Ishodu]

Your 192 that gave out was probably leaking and causing the engine to run cooler than 180. Now that you got a new 180 its actually reaching that temp. Just a thought but it would be better to know exactly the temp like Sdpatt said.

 

[Off Road SHO]

When you changed out your old thermostat, it was because it was letting the engine run too cool, it was probably stuck "open". This would give you a low temperature reading on your dash's temp gauge.

By putting in a thermostat that actually worked, that is, kept closed until the coolant heated up, you made the coolant run where it was supposed to be, in this scenario, 180 degrees.

You can keep replacing more things hoping to change your interpretation of the actual heat of the engine, or you can do as Scott suggested and verify the "actual" temperature of the water as it leaves the thermostat housing on its' way to the radiator using an infrared thermometer.

If you don't want to spring for an Infrared, non contact thermometer, you can always use the old Rube Goldberg method of a kitchen type candy thermometer and fasten it in some way mechanically to the thermostat housing. It has to be in good thermal contact, not just touching.

Tom

 

[Red Baron]

Off Road SHO:
When you changed out your old thermostat, it was because it was letting the engine run too cool, it was probably stuck "open". This would give you a low temperature reading on your dash's temp gauge....

You can keep replacing more things hoping to change your interpretation of the actual heat of the engine, or you can do as Scott suggested and verify the "actual" temperature of the water as it leaves the thermostat housing on its' way to the radiator using an infrared thermometer....


Tom

Actually, my car kept heating up to the point that it boiled over a couple of times and my radiator had to be replaced (the joint where the plastic and metal meets separated)...so I replaced the radiator..then I found out that my t-stat was messed up, that's when I changed it out...no problems of overheating since, just the higher temp. reading (on the gauge)

The infrared thermometer...is that the one that "shoots out a laser" (like a pointer)and reads the temp.? If so, do I put the laser point on the hose (leading from the t-stat housing to the radiator)? Thanx for all of your help.... hail

 

[Off Road SHO]

No, you put the laser spot on the pipe right next to that hose. The laser spot you see is just the center of the spot that is read by the infrared receiver inside the unit. The "read spot" gets bigger as you move the reader away from the surface.

The acceptance cone spot is about 1" in diameter when the receiver is at 3" from surface.

Did I confuse you enough yet or should I keep trying.

Tom

 

[Red Baron]

[
The acceptance cone spot is about 1" in diameter when the receiver is at 3" from surface....



Tom [/QB][/QUOTE]

That's the only part that confused me ...You'll probably want to slap after all of my questions....Thanks for your help.

 

[Ishodu]

Redmase its like a shotgun the farther you hold the unit away from the test point the larger the test area will be.

 

[Red Baron]

oh Now i get it....I'm getting one to read the temp. and I will post sometime tomorrow...thanks...here's to you... beer

 

[SHOZ123]

If you overheated your engine there is a good possibility the temp sender for the gauge is now out of calibration and not giving an accurate signal. This may be why the needle is not in the right spot. If the sender is good the "M" is ~190F.

 

[Red Baron]

Well...I took the temp. of the car...I aimed the spot at the base where the t-stat housing is and got a temp. reading of 213F...the needle on the gauge was a tiny bit above the R, but still on it....

I don't know if this is normal, or what... Thanx.

 

[SHOZ123]

The approximate temp readings to letter correlation is...

L=140F
M=190F
R=200F
O=220F
N=230F

The fan should be coming on between the R and O, this is a good way to see if the temp sender is accurate as the fan is controlled by PCM to come on at 215F and gets the info from the ECT sender. This is a much more accurate sender and can be counted on usually.

Above the Hot line is in excess of 235F. These numbers are all +-3F and are with new and properly operating equipment.

 

[Red Baron]

Thanks for all of your help....