Engine temp- Bronco too cool

[White Knight]

I have an aluminum radiator, new high flow water pump, 185 degree thermostat … engine is a 302 with mild E303 cam, SVO heads, long tube headers, new Holley 600 carb, automatic. I’m in Alabama in 95 degrees and temp doesn’t get higher than 170. Seems it should get to 185-200 at least. Is something wrong or am I just fortunate it doesn’t overheat??

 

[green61bug]

Did you happen to check the manifold with a temp gun to make sure the gauge was reading accurately?

 

[ared77]

"Bronco too cool"​

They can't help it.

 

[steelworker77]

My factory gauge was reading the same thing in stop and go traffic in 95-100* heat the other week and I checked it with a temp gun and sure enough it was about 190*. At least my factory gauge seems to be roughly 15-20* lower than it actually is.

 

[Broncobowsher]

I will start with suspecting the gauge isn't accurate.
Next is the thermostat not accurate. I've had a lot of variability in thermostats over the years. One high flow would take 15 miles of highway driving until it was finally holding its rated temp. It was cracking open way too soon, but did good regulating, eventually. Best one was a factory Ford replacement '89 Mustang thermostat. Fast warm up, once warm it was stable. Since it was for emissions, fast warm up was important. I think this is a case where the aftermarket is trying to keep stuff cool while factory stuff is trying for a fast warm up and keeping stuff clean.
Factory gauges, never known for accuracy. It's about what it says, with a lot of room around that "about"

 

[White Knight]

I drove in a parade for an hour in 95 degree weather and still didn’t get above 175. Going to get a temp gun and also a new motorcraft sensor see if that helps-

 

[SteveL]

You could test your t-stat in a pot of water with a thermometer.

 

[jamesroney]

I have an aluminum radiator, new high flow water pump, 185 degree thermostat … engine is a 302 with mild E303 cam, SVO heads, long tube headers, new Holley 600 carb, automatic. I’m in Alabama in 95 degrees and temp doesn’t get higher than 170. Seems it should get to 185-200 at least. Is something wrong or am I just fortunate it doesn’t overheat??

That thing on the dash has nothing to do with the actual temperature. If you have a functional 185 thermostat then your engine is operating at 185 degrees.

If you really care about the accuracy of your engine temperature, go find a mechanical capillary gage, (like $21.00 on Amazon) verify calibration it in a pot of boiling water to ensure that boiling reads 212. Then run it in your Bronco. You will find that you are much hotter than you think you are.

I drove in a parade for an hour in 95 degree weather and still didn’t get above 175. Going to get a temp gun and also a new motorcraft sensor see if that helps-

It won't help. You are flying blind. The IR temp guns are notoriously inaccurate depending on the target. But they are very useful for looking at differences. You should own one just to have it. But if you want to know the coolant temperature then you really want to use a capillary mechanical gage that you have calibrated.

Don't bother to install it in the dash or cab. Just leave it under the hood, or you can bring it in thru the wing window if you really want to see it while driving. It is a diagnostic tool at this point. Not an instrument.

 

[Broncobowsher]

We'll do this again, What gauge are you using to determine it is only getting to 170-175?
Odds still are you are using the factory gauge. Which isn't anywhere near accurate.

Everything you describe, you have a perfectly functional cooling system. You are chasing a gauge accuracy problem with mechanical parts. You don't really have an issue. Even if it is really running 170-175 that isn't really a problem.

 

[DirtDonk]

Depending upon how much you use your heater in the winter that is.
When my gauge read 160, the air coming out of the vent was luke warm.

Gauge was as accurate as I could test it with the tools back then. No IR thermometers at the time. Just kitchen thermometers!