So ever since I switched to a 180 tstat and put in a new radiator, my heat has been non existant except on a couple choice days. Any ideas? The system is all bled and such, heater core doesn't leak so it should still be good

 

I'm already guessing that the radiator is full of antifreeze? lol Start with the common problems first

 

Possibly the stat is hanging open? Does your gauge show any reading?

 

Truck is full on coolant. On the old radiator and 195 tstat it used to run on the N in normal. With the 180 and new radiator it runs in the red shaded area of this pic, normally on the bottom half of the shaded part. And if anything on the stat, it'd be not opening fully. When I was gettin the rad fixed after I did the water pump I had my mechanic over to check it out and apparently the coolant doesnt jet through the rad like is "normal" which to him signalled that there was a blockage most likely in the thermostat (because everything else cooling related had been replaced).

 

I'd put a real guage on it before getting too concerned. The temp senders are really not scientific... I've tried a few and many older posts talk about the senders giving different readings.

I changed out the sender on mine this week, the old one had always stuck right at the O. It would sweep a bit (like your red zone in your artwork), but not even the width of the O. I replaced it because the needle recently started to wander all over the place.

My new sender (with nothing else changed) now reads steady again with a small sweep as the stat opens/closes, but it sticks right at the M on the guage.

So... I know that the truck is running at the same temp, but the guage shows it differently. But without getting an accurate reading with numbers on it, who knows what the exact temp is.

I also read in an old post that someone had tried the 195°, 180°, and 160° stats and with their sender, they read at about M, O, and below N respectively on the guage. Maybe the cooler stat is just showing lower (as expected) on your guage?

 

A blockage anywhere would cause the engine to overheat, and if the stat was not fully open, there would be flow through the radiator and still keep the engine cool due to the constant flow through the radiator. How are your hoses? Are they collapsing? This would cause a flow restriction.

 

And you're in Florida, right? Do you guys even use the heater?

...please don't say it's been really chilly in the 60's at night - I'll cry!

 

It's 330 on the North Florida Gulf Coast this morning!

It's a wet cold.


I'm thinking it's the new thermostat that is staying wide-open because of your heater not blowing warm/hot air except for the couple of days,
replace the thermostat again.

All I got.

 

you dont even need the heater down their, it gets a little hairy when it dips to -40F up here in canada

 

Put the required 195 t-stat back in, and check the heater hoses, both need to be basically the same temp (hot) for the heater to work. Tell your mechanic friend that the coolant will flow thru the heater core even if the t-stat is stuck. Follow the hoses, it goes around the t-stat.