thermostat question

[sambudo]

What thermostat is the correct one does it matter which one you use? I recently replaced mine with a 195 degree. I live in the PNW, and it can get cold in the winter. do theses take a while to get warmed up? I don't know, i have the i-6 250. When i look at my temp gauge it doesn't look like it works. i don't see the pointer in the gauge. should i be able to see it? or do i have to wait until the car warms up? I've never noticed it worked. Only had the truck for 1 mo. slowly going thru and repairing what I can.

[sambudo]

this is what i tool out looks like it was 180degrees.

[WIDESIDE72]

I would stick with the 180 or even a 160. No need to run a 195. Those didnt really come into use til emission engines in the 90's trying to clean up exhaust gases with higher temps.

Sounds like your gauge is broken.

[bigmac73]

I would unhook the gage wire from the sending unit and ground it to the block, and see if the gauge moves, i think it should jump up if it is grounded

[cdowns]

the 195 is fine and makes the cab ALOT more comfortable to be in in a shorter amount of time/// where u live it will raise the driving comfort level considerablly in the winter

[Andy4639]

The thermastat will open at 190 degree's. This in turn will give you better heat. The needle should be up in the gauge so U can see it once the motor has warmed up to correct temperature. Is the temp wire hooked up to the senor on the engine?

[MARKDTN]

Nothing wrong with a 195. Why would you want a 160 if you are trying to make the heater work? Use a good quality t-stat. I only use GM or Robertshaw, I have had bad luck with discount house brands. Sounds like your gauge may be bad. You can replace it or have it rebuilt if it tests bad.

[sambudo]

Originally Posted by Andy4639

The thermastat will open at 190 degree's. This in turn will give you better heat. The needle should be up in the gauge so U can see it once the motor has warmed up to correct temperature. Is the temp wire hooked up to the senor on the engine?

yes it is, how long does it typically take for one of these engines to warm up? When i tested it last night it ran 1/2 hr but still was cold.

[sambudo]

Originally Posted by MARKDTN

Nothing wrong with a 195. Why would you want a 160 if you are trying to make the heater work? Use a good quality t-stat. I only use GM or Robertshaw, I have had bad luck with discount house brands. Sounds like your gauge may be bad. You can replace it or have it rebuilt if it tests bad.

I bought a discount brand. How does one get the oem gauge rebuilt? can you take that gauge off individually and seperate from the dach cluster?I'll try it again tonight. Thank you everyone for the great information.

[msgdsrf]

Sounds to me like you've now check the gauge but you may still need to check the snding unit. 10-15 min to warm up at most.

[PanelDeland]

Is the heater blowing warm? You may have a plugged heater core,either the tubes or the heater box may be plugged with leaves,a rats nest or other debris.Try feeling of the hoses and see how warm they are.Check the radiator hoses to see if they're getting hot,if they are check both hoses going to the heater,one should be pretty hot and the other warm.If either or both are cold then the core isn't getting hot water.Is the temp cable hooked up to the valve(non-AC)?

[Andy4639]

Originally Posted by sambudo

yes it is, how long does it typically take for one of these engines to warm up? When i tested it last night it ran 1/2 hr but still was cold.

U ran the truck for .30 minutes and it wasn't warm? U have either put the thermastat in backwards are as P/D has said the core is stopped up are the heater isn't working. Look at the heater hoses and see if the water valve is open and letting the water circulate through the heater core.
Don't worry about the picture it shows the AC lines to. Focus on the heater lines.

[MARKDTN]

Originally Posted by sambudo

I bought a discount brand. How does one get the oem gauge rebuilt? can you take that gauge off individually and seperate from the dach cluster?I'll try it again tonight. Thank you everyone for the great information.

OEM gauge can be rebuilt by anyone that does GM gauges. maybe CorvetteClocksByRoger or just Google "gauge cluster rebuild". I can't find the other one I have used. Something like d&m repair in the Carolinas.

[swamp rat]

Originally Posted by msgdsrf

Sounds to me like you've now check the gauge but you may still need to check the snding unit. 10-15 min to warm up at most.

Absolutely something wrong here, i wouldn't go below a 185 degree thermostat for this area, personally i run a 190. A performance guy might squeek a tiny bit more horse power out using a cooler thermostat but its not worth it.

Make sure the thermostat is installed right side up, and also check for proper hose routing. When the thermostat (about 10 minutes run time) opens it sends warm water thru the heater core regardless of if the heater is turned on or not so both the hoses should also be warm, if there not then the core could be blocked or hoses routed improperly, the only way to check is to pull the hoses and put some low pressure air or water thru to check the flow and look at the manual for routing.

Have you checked the cowl for debre built up thru the years? that can block the air from entering the heater, might even need to pull the hood hinge on the passenger side and then pull the electrical heater motor and check for crap build up there as well, that can and has been known to damage the squirrel cage.

[sambudo]

Originally Posted by swamp rat

Absolutely something wrong here, i wouldn't go below a 185 degree thermostat for this area, personally i run a 190. A performance guy might squeek a tiny bit more horse power out using a cooler thermostat but its not worth it.

Make sure the thermostat is installed right side up, and also check for proper hose routing. When the thermostat (about 10 minutes run time) opens it sends warm water thru the heater core regardless of if the heater is turned on or not so both the hoses should also be warm, if there not then the core could be blocked or hoses routed improperly, the only way to check is to pull the hoses and put some low pressure air or water thru to check the flow and look at the manual for routing.

Have you checked the cowl for debre built up thru the years? that can block the air from entering the heater, might even need to pull the hood hinge on the passenger side and then pull the electrical heater motor and check for crap build up there as well, that can and has been known to damage the squirrel cage.

Really good information everyone. I'm starting to think i put the T-stat in wrong, spring side down? I ran it tonight and the hose that goes from the bottom of rad to block came off. The seal was not strong enough as it leaked out the bottom. it seemed to start getting hot then the water shot out. Can i run straight water through it until i can get the hose secured to the radiator?, i noticed. I'm going to look not the heater, doesn't seem to be working.

[Andy4639]

Thermastat spring goes down into housing. It also has a front and back though I have never had any problems with it in any I have installed. U need to make sure U get all the air out of the system as well. This will cause all kinds of heating and cooling problems if air is traped in the system.

[TBONE1964]

First of all, I would like to ask what was the condition before you changed the t-stat? Did you have the same problem as you do know?

Either way you have what sounds like two separate problems.

As others have mentioned, check for heat at the heater hoses after the truck has ran for at least ten minutes. They should both be warm. Sounds like you might have figured it out already.

If you need a cluster repair, send me a PM. I also can sell you a good known original style working temp gauge for your cluster. Use caution when grounding the wire to the sending unit as it will damage the gauge if you are not careful. Another thing to consider with your gauge issue,, is your temperature sending unit.

Keep us posted.
Tom

[sambudo]

Originally Posted by TBONE1964

First of all, I would like to ask what was the condition before you changed the t-stat? Did you have the same problem as you do know?

Either way you have what sounds like two separate problems.

As others have mentioned, check for heat at the heater hoses after the truck has ran for at least ten minutes. They should both be warm. Sounds like you might have figured it out already.

If you need a cluster repair, send me a PM. I also can sell you a good known original style working temp gauge for your cluster. Use caution when grounding the wire to the sending unit as it will damage the gauge if you are not careful. Another thing to consider with your gauge issue,, is your temperature sending unit.

Keep us posted.
Tom

Tom, i can't answer this as I just purchased the truck 1 month ago. I did some work on the radiator, so I thought it's a good time to replace T-stat. How do you check the temp sending unit if good or bad?
I havent looked into the gauge if hooked up yet or not, I can't see the needle. I need to get the hose to radiator hooked up correct, with no leaks.

Is it ok to run plain water until I figure the hose issue problem? Hope to problem slove this weekend. Thanks for all the great responses.

[Andy4639]

U can run plain water as long as U don't let it freeze. Sitting over night depending on where U live.

[motorcritter]

I wouldn't run straight water any longer than it takes to sort out the problem, not just freezing damage, but internal corrosion, too. I recommend checking the wire from the sensor to the gauge, age, heat, vibration and handling may have damaged it- no continuity=no gauge reading.

[sambudo]

Well I didn't have much working time on the problem. I did take off the hose that goes into the water outlet. I did what I didn't think I did, and thats put the T-stat in the wrong way. I did! So I will reinstall it tomorrow. Stay tuned. Thanks for the help!

[swamp rat]

That should help it open sooner!

[sambudo]

Well now that I have the theromstat installed correctly and heats up in 10 minutes, and leak issues. I still do not have the temp gauge working. I will work on this and make sure that it is connected properly. Then check the heat sending unit. Do i need to pull this out to check if working properly?

The heater does not work, i need to replace the heat hose under the dash, and the bottom lever is missing from my heat control. looks like all hooked up in the back, just no lever.

Also after the car heated up the radiator hoses were warm and the heater hoses were very hot, is this normal? Thanks again for everyones input.

[Andy4639]

The heater does not work, i need to replace the heat hose under the dash, and the bottom lever is missing from my heat control. looks like all hooked up in the back, just no lever.

Also after the car heated up the radiator hoses were warm and the heater hoses were very hot, is this normal? Thanks again for everyones input.

Can U explain this a little better.
What heater hose under the dash are U speaking of?
The lever missing is it the fan switch? I'm not real sure for a non AC truck.

[swamp rat]

Originally Posted by sambudo

Well now that I have the theromstat installed correctly and heats up in 10 minutes, and leak issues. I still do not have the temp gauge working. I will work on this and make sure that it is connected properly. Then check the heat sending unit. Do i need to pull this out to check if working properly?

The heater does not work, i need to replace the heat hose under the dash, and the bottom lever is missing from my heat control. looks like all hooked up in the back, just no lever.

Also after the car heated up the radiator hoses were warm and the heater hoses were very hot, is this normal? Thanks again for everyones input.

The 5/8 and 3/4 heater hoses will be as hot as your water temp, if a 190 thermostat then at least that hot probably even a bit hotter because the water that flows to the heater just went thru the engine. The Heater core will always have hot water flowing thru it.

The bottom lever controls a flap door inside the heater body, the door is what allows the air to flow across the heater core. If i remember correctly the air flows from the blower, then to a door which allows ether, none, all or part of the air to flow across the heater core, if it allows none then the air goes around a bypass and comes out ether the heat or defrost outlets depending on the position of that control. The door is moved depending how far you push the lever to the hot or cold side, and by varying the air across the heater core is what controls the temperature.

The temp gauge is very possibly the sending unit which is usually screwed into the head but not sure on your engine. The sending unit is not suppose to have Teflon tape on the pipe threads as the threads are the ground. Auto parts stores sell sensor safe thread sealer made for this application.