Heater and T-stat?

[Pont406]

I run 160 t-stat in my 69 c10 during the winter time. My heater barelly gets warm. Unless I am stuck in heavy traffic and temperature climbs to 180 it will work. Right after I am moving it's back to 160 and no heat. It gets to low 40s at night and I need to get some more heat. So, what are you guys running for t-stat during winter time?

[leddzepp]

Hi neighbor, I run a 180 thermostat in both my trucks year round. No problems with the heater or overheating.

[cdowns]

hot thermo =toasty cab

an added bonus is the motor runs more efficiantly too

[Longhorn Man]

put a 195 t stat in there... 180 at the minimum

[Pont406]

That's one thing i noticed is that a motor very responsive under 170. It also looses about 8-10 hp when at 190. How important are door seals? Mine are new but wont stay in place and leaking air.

[mr48chev]

You answered your own question when you said that when the truck warms up to 180 the heater actually kicks out heat.
It's 25F outside right now and I just made a 70 mile run with a 180 thermostat and it barely warms up enough to make the cab comfortable.
I have to ask, how can you tell that you loose 8-10 hp when the truck runs at 180 or a bit higher or is it all in your head?
Back when everyone ran hotwater Chev sixes or flatheads anything over about 180 was pretty warm but on modern engines 180 is just getting up to good operating temp for most street engines and the old ideas really don't stand up.

Or do like guys did for 50 years or more and put a bit hotter thermostat in for winter and a cooler one for summer. That used to be the normal thing to do in the 50's.

[Stocker]

I run a 195 year-round, good heat in winter and never overheats in summer. I'm not inclined to change the t-stat twice a year if I see no benefit.

[TheOldGM]

I have the same problem with a 195 thermo. Every winter, I put a cardboard square in front of the radiator. When it is going to be warmer (30 degrees +) I have a flap cut out that I flip up to let a small amount of air in, otherwise it is almost completely blocked. It is almost required in WI where winters are pretty cold...

[Pont406]

I had the truck on chasis dyno thats how I know it looses power.
My ex was over tonight and she found another problem with the heater. My fresh air flaps were open. I was able to close right flap but left flap is broken. I need to close it and see what happens. I believe that a mounting is rusted out.

[71tahoe]

Originally Posted by Pont406

I had the truck on chasis dyno thats how I know it looses power.
My ex was over tonight and she found another problem with the heater. My fresh air flaps were open. I was able to close right flap but left flap is broken. I need to close it and see what happens. I believe that a mounting is rusted out.

The vent flap is hanging half out on the driver's side and probably binding. If you can re-install the flap (looks like the bottom pin) it might close. Also, you may have trash/leaves packed around the heater core not letting air through. 160 should still be enough to heat at 40 deg.

[airdale94]

I run a 180 in mine and it gets plenty hot in Kansas. I would think a 160 would be plenty for LA. If your temp. climbs while idle it sounds like you have a cooling issue. Either your fan or radiator flow. It sounds like a flow problem if your heater isn't heating up. Your radiator and heater core might be resticted. Your thermostat might also be the problem. I like to run the Hypertech PowerStats. They have a more controlled flow. They will open in incremental ammounts, where others are either opened or closed.

[69GMCLonghorn]

Originally Posted by airdale94

I run a 180 in mine and it gets plenty hot in Kansas. I would think a 160 would be plenty for LA. If your temp. climbs while idle it sounds like you have a cooling issue. Either your fan or radiator flow. It sounds like a flow problem if your heater isn't heating up. Your radiator and heater core might be resticted. Your thermostat might also be the problem. I like to run the Hypertech PowerStats. They have a more controlled flow. They will open in incremental ammounts, where others are either opened or closed.

I have to agree with this. I ran a 160° T-stat for years and drove the truck in weather down to about freezing. I never had a problem with lack of heat. If you have all those weatherstripping problems, solve those first. Then see if the heater is keeping up with the need. If not, here's a small laundry list of stuff you might already know:

1) Check the heater system thoroughly and make sure the doors are opening all the way. There are 3: 1) main airflow 2) controls how much heat and 3) defrost of floorboard control.

2) Make sure the heater box isn't full of leaves. If you're not getting the air flow you need, you'll never get warm.

3) Make sure your fan is getting to the 3rd position. Once I fixed my switch, it blew like a 10 cent whore on Nickel Night.

4) This time of year, that thing should sit at 160° all day, even in traffic. I'd have your system tested to see what's plugged. Someday, it'll be hot again. You'll want to catch this before it gets worse.

5) Guys, you're going to contradict me, but I DARE you to tell the diffference in power or driveability between running a 160° and a 195° T-stat. Unless you're running a super high output motor, you won't tell a difference! Mine had a 195° in it when I rebuilt it with 10.0:1 heads, lopey cam, and copious amounts of advance. I dropped in a 160 when I had the radiator gone through and never felt a difference.

[Pont406]

It's not overheating. It's got a biggest summit radiator, trans cooler and a new summit heater core. 160 t-stat with dual fans from a 4th gen fbody. Fans come on at 200 and off at 180. Right now cooling fans are not coming on at all. Unless it's idling for a long time.
No super high output motor. 310 hp at the wheels at 170 and down to 304 at 190.
Too cold to do anything right now. Doors were frozen shut this morning.