Last question before Christmas...I'm not HOT

[mally002]

Greetings all,

I hope you guys don't throw me off because of all my questions. I noticed yesterday and today( here in Knoxville, TN it's been in the low 60's) while driving my temp gauge is just barely moving past 120. I went on the interstate for about 4 miles after a 15-20 mile leisure drive and thought maybe it should register hotter. I figure I will go ahead and replace the thermostate next week, unless you guys think otherwise.

I did do a search on this but the post that came back addressed "over heating" not "under" Is this cause for alarm, or just normal.

Again, Thanks.

Randy

[EScanlon]

Greetings all,

I hope you guys don't throw me off because of all my questions.

Nope, but you might consider making a donation to the Club Site to help fund the server upgrade! If the information you've received here has saved you time and money, put a few dollars back into it to help EVERYONE.

I noticed yesterday and today( here in Knoxville, TN it's been in the low 60's)

It's not nice to brag about that...look at our members in Colorado!

while driving my temp gauge is just barely moving past 120. I went on the interstate for about 4 miles after a 15-20 mile leisure drive and thought maybe it should register hotter. I figure I will go ahead and replace the thermostate next week, unless you guys think otherwise.

I did do a search on this but the post that came back addressed "over heating" not "under" Is this cause for alarm, or just normal.

Again, Thanks.

Randy

The Temperature sender operates on resistance. Before you start tearing the car down and addressing fictitious gremlins verify that it is indeed NOT heating up.

The gauge's inaccuracy may be the bigger gremlin here than the engine NOT heating up.

You don't mention whether you're getting heat out of the Heater, so....

There will no doubt be some discussion here by some of the more mechanical guru's, but these are some basics:

To verify the Temperature sender's operation, first remove the cap from the radiator and with a mechanic's type thermometer (not your Mom's Turkey Spike) put it into the water/Anti-Freeze mix.

(DO NOT WARM UP THE ENGINE FIRST AND THEN OPEN THE RADIATOR...THAT IS EXTREMELY HAZARDOUS AND COULD CAUSE SERIOUS SCALDING!)

Start the car and once it's running smoothly let off the Choke.

Observe the water flowing in the radiator and check the temperature. At the temperature that you notice a marked increase in the water swirling around the opening make a note. That's the rating for your Thermostat Valve. That is the temperature at which the valve opens and allows the coolant to flow through the radiator to be cooled.

Allow to run for a small amount of time and keep track of the temperature. This will give you an idea as to the cooling properties of your non-pressurized radiator. It's not usually necessary to run for a long period of time.

Compare the temperature you note at each step with what you see inside the car on the car's gauge.

If there is a large difference, you can replace the sender on the engine and see if that rectifies the reading.

The gauge has adjustment's on it, but it would definitely be a trial and error as there are no established procedures nor bench marks as to how to proceed. Additionally, usually just replacing the sender eliminates the erroneous readings.

Don't forget that the gauge is not a rated measurement instrument...it's an approximation based on resistance and not designed to be interpreted as being a calibrated gauge.

Hope this helps.

Enrique

[Alex 240Z]

Thanks for the excellent explaination EScanlon !!!! That cleared a few things up for me !!!!!!!!!!!!!