heater not hot

[third_shift|studios]

my heater just isn't pushing out the hot weather it used to...is that a stuck t-stat?. i have a stock t-stat on a 2000 ls1

[Mr. Luos]

Turn it over to the red part.

[shady milkman]

Turn it over to the red part.

[BlackLT1Z28]

Flush the radiator.

[greenvilleTA]

Is it over heating or is the temp. normal? If the tstat was stuck, you would most likely overheat or see an elevated temp. I'd start the car while cool, then take the radiator cap off while still cool, and as it warms up, you should see the fluid level slightly drop and see fluid pumping through radiator passages visible with the cap off. If after completely warm the water is barely moving, probably stuck tstat...if not circulating at all, maybe waterpump. Since tstat is cheap and a 5 minute replacement, I'd start there.

[0rion]

Take the cap off the radiator when it's cold and start it up. If the coolant immediately starts circulating then your t-stat is stuck open. I would look at that first then reverse flush the heater core if it's not the t-stat. I've ran into both situations in the last 2 months on different vehicles. Both have pretty much the same symptoms. The heat will get warm but not hot and takes a long time to get warm.

[juiced99ws6]

Take the cap off the radiator when it's cold and start it up. If the coolant immediately starts circulating then your t-stat is stuck open. I would look at that first then reverse flush the heater core if it's not the t-stat. I've ran into both situations in the last 2 months on different vehicles. Both have pretty much the same symptoms. The heat will get warm but not hot and takes a long time to get warm.

crappy thing about the f body i syour gauge wont tell you if your car is running colder than normal.

[Allen Wood]

Check the coolant/water level. No liquid no heat.

[juiced99ws6]

no liquid= LOTS of heat

[third_shift|studios]

thanks, i'll have to report back after i do some testing tomorrow

[third_shift|studios]

Take the cap off the radiator when it's cold and start it up. If the coolant immediately starts circulating then your t-stat is stuck open. I would look at that first then reverse flush the heater core if it's not the t-stat. I've ran into both situations in the last 2 months on different vehicles. Both have pretty much the same symptoms. The heat will get warm but not hot and takes a long time to get warm.

i took of the cap, started the car and didn't see any liquid at all? am i really low on coolant? or is it so far down that it's too dark to see w/out a light?

[Allen Wood]

There could be enough water to keep the engine from over heating but not enough to provide heat. I should have said the coolant level could be low and this will cause the heater not to put out any hot air.

[0rion]

I would definitely top it off. Sounds like you're just really low on coolant. Leave the cap off and keep topping it off until it's full and that'll purge any air out of the system. Make it a habit to start using the overflow reservoir and keeping an eye on it. That'll keep you from running so low.

[third_shift|studios]

i guess i have a slow leak. seems like every 6 months i have to top it off.

so do i pour into the radiator or the overflow tank?

I would pour it into the radiator until that's almost full and let the car come up to temp ( the level will rise as it comes up to temp), then let it run a bit to flush any air that might be in the system out ( 5-10 min), put the cap back on and let the car come completely up to temp, and fill the resevoir up to the "full when hot" mark.

[juiced99ws6]

There could be enough water to keep the engine from over heating but not enough to provide heat. I should have said the coolant level could be low and this will cause the heater not to put out any hot air.

i was just busting your chops.. it just came out funny and was too good to resist.

[LS2Tuner]

i guess i have a slow leak. seems like every 6 months i have to top it off.

so do i pour into the radiator or the overflow tank?

I would pour it into the radiator until that's almost full and let the car come up to temp ( the level will rise as it comes up to temp), then let it run a bit to flush any air that might be in the system out ( 5-10 min), put the cap back on and let the car come completely up to temp, and fill the resevoir up to the "full when hot" mark.

Into the rad. and then just top off the over flow every couple weeks.

And last but NOT LEAST GO TO SKYLINE AND EAT 4 3-WAY FOR ME!!!!

[0rion]

Well, not sure what happened to my last post. It never showed up.

Fill the radiator almost full but leave a little room because the level will rise as the car heats up. After it runs a while and the coolant is circulating let it run a bit (5-10 min) to flush any air out that may be in there. Put the cap back on and let the car run a bit to get good and hot and fill your reservoir then.

[third_shift|studios]

Into the rad. and then just top off the over flow every couple weeks.

that doesn't make any sense; to fill both the radiator AND the overflow?

[0rion]

What he's saying is to fill the radiator now then check back and top off the overflow every couple of weeks. What happens is that as the water gets hot and expands it's pushed into the overflow tank. That's why after this intial fill you fill at the overflow and only when the car is hot, so it doesn't push water out of the overflow.

[LS2Tuner]

What he's saying is to fill the radiator now then check back and top off the overflow every couple of weeks. What happens is that as the water gets hot and expands it's pushed into the overflow tank. That's why after this intial fill you fill at the overflow and only when the car is hot, so it doesn't push water out of the overflow.

Thank you Sir for explaining it in plain english.