No Heat!

youngjeeper11 · 02-24-2005, 07:45 PM

middle of winter here in PA, middle of a snow storm, and I have no heat!! lol, could it be the thermostat? and if so, where is the thermostat? i could not find it. my radiator is a little leaky, could that have something to do with it?

rockjock · 02-24-2005, 08:19 PM

Well tell us a little more. Did it stop blowing? Is it just not blowing hot? Where you moving the temp slide thing? Where there any symptoms leading up to the problem?

Cheers
RJ

JOKER4INK · 02-25-2005, 01:22 AM

The first thing to do is check to see if you have any antifreeze. Without antifreeze, you will not get any heat in your vehicle. Pop open the reservoir cap and see if you have enough antifreeze. Then remove the radiator cap and see if you see any antifreeze. If you have enough, it could be the thermostat. Follow the hose from the top of the radiator to the engine. The thermostat is located on the engine just about where the hose and block meet. Those are the main reasons for lack of heat.

94YJ H.O. · 02-25-2005, 03:08 AM

I agree, it sounds like a bit more info is needed to figue out whats going on with your heater.

On my 90 Bronco I could always tell when it was time to put more coolant in the overflow tank because the heater wouldn't blow nearly as hot as it normally did. Make sure the engine is cold when you take of the radiator cap, hot coolant hurts

.

Unless the engine was overheating, I don't think that the thermostat is the problem.

**ltmke11** · 02-25-2005, 08:19 AM

This sounds dumb but on the passenger side (just under the dash there is a wire) I frequently nock the "wire clip" which attaches to the heat switch which lets the heat "loose" when you turn the switch.

I seem to nock mine off at least once a month and all it will do is blow cold air.

or else it could be the actual heater core is shot?

bono426 · 02-25-2005, 08:52 AM

hahhaha join the club! my heater is broken also and it has been freezing! i think it just snowed 6" last night so yea. i know what is wrong with mine though, blower motor i just dont have the time to fix it. so now im stuck freezing my as$ off. oh yea and my drivers side window wont stay up lol.

good luck
charlie

youngjeeper11 · 02-25-2005, 02:13 PM

mine is still blowing, just not hot, and I definityl have anitfreeze, beacuse that was the first thing i checked, the resivoir is only 3/4 of the way full though.

pyro9862 · 02-25-2005, 03:05 PM

Quote:

Originally Posted by 94YJ H.O.

Make sure the engine is cold when you take of the radiator cap, hot coolant hurts

.

Or get one of those nifty radiator caps that lets you blow off the pressure without loosing any liquid

youngjeeper11 · 02-25-2005, 03:53 PM

also, what excactly does the thermostat look like? is it just a little sensor thing with 2 wires coming out?

rhinoss · 02-25-2005, 04:42 PM

Quote:

Originally Posted by youngjeeper11

also, what excactly does the thermostat look like? is it just a little sensor thing with 2 wires coming out?

You could have a sensor in the thermostat housing. Follow the upper radiator hose from the radiator down to the engine. Where the hose connects to the engine you should find the thermostat housing. The thermostat is inside that housing.

It should look similar to this:

rhinoss · 02-25-2005, 04:45 PM

To test the thermostat if you'd like, although if it's suspect I typically replace it anyway.

To test it, you can heat it up by dropping it in boiling water to see if the plunger opens up.

What happens if you leave the jeep idling for 10 to 15 minutes. Does the heater heat up at all?

pyro9862 · 02-25-2005, 04:58 PM

Ok, it's blowning cold air, you have antifreeze.
Next questions.
Did you do anything at all when it stopped working, flush the antifreeze, etc? It is possible to have air in the system keeping it from getting water to some places.
Next what does your temp guage say, is the coolent warming up?
If the coolent isn't warming up then we start looking at a stuck thermostat. If it is start looking at the heating system.

youngjeeper11 · 02-25-2005, 05:43 PM

the engine warms up, but hot air doesn not come out at all, even after 30 minutes of driving. so what next?

now that you mention it, it hasnt worked since I flushed the antifreeze, so if there is air in there, how do I get it out?

massyj · 02-26-2005, 01:14 PM

To try and knock out the air from the hoses, run the engine with the radiator cap off. You might be able to get an idea if there is an air bubble by squeezing one of the tubes and seeing if its empty or not. It COULD be that your heater core is jammed, in which case a good flush of it could help. The heater core is in the interior, but the 2 hoses that go in and out of it are under the hood about a foot to the right of the battery near the top. they are on top of each other. When mine was messed up it was simply that the heater control hose was bent, so regardless of the switch position, it was cold air. Since she's heating up all the way, that means your thermostat should be in good shape. Best of Luck Bud.

dcafaro · 02-26-2005, 01:35 PM

Just solved the same exact problem. Here is how I resolved the issue.

Let the Jeep get to operating temp and make sure your gauge is registering. It probably won't get to 100% operating temp on the gauge but as long as something registers. If gauge reads proceed.

Check all hoses and make sure you're getting fluid through them by simply squeezing them. At this same time get an idea if they are warm hot cold etc. I would start with the upper and work your way back. The upper hose should be hot and sometimes pressurized. Then go to the the smaller hose to the right coming of the t-stat housing (WATCH YOUR FINGERS AND HANDS AROUND THE FAN, IT STICKS OUT MUCH FURTHER THAN THE EYE CAN SEE!!!!!) IT should be at least warm and it travels into the manifold (I think). From there your lower heater core hose comes out of the manifold and over to the heater core fitting near the battery, this should be hot. Then check the upper heater core hose, it to should be at least very warm, but less than hot, (the coolant has traveled through the core and has cooled some so it won't be as hot as it was going in). This hose goes into the water pump. Finally check your lower heater hose and be very careful as before or even turn the engine off at this point. Again it should be warm but not hot as fluid has traveled throught the radiator and cooled.

If the hose going into the core is hot but the one coming out is much cooler then your core is shot and you need to replace it, which was the case with mine (it's not really that big of a project, the air box comes out easy but it takes a bit to line everything back up to reinstall it If the there is no warm fluid passing through the smaller hose coming out of the t-stat to the right then I think your t-stat is shot (however if you get to normal operating temp without overheating your t-stat is fine.)

Also check your pump, at the top under the t-stat housing, check to see if you have fluid dripping. Your pump housing has a weep hole in it and will drip when the pump is starting to fail.

02-25-2005, 03:08 AM	#4
94YJ H.O. Registered User Join Date: Jan 2005 Location: West Valley City, Utah Posts: 777 Profile Gallery Classifieds My Jeeps	I agree, it sounds like a bit more info is needed to figue out whats going on with your heater. On my 90 Bronco I could always tell when it was time to put more coolant in the overflow tank because the heater wouldn't blow nearly as hot as it normally did. Make sure the engine is cold when you take of the radiator cap, hot coolant hurts . Unless the engine was overheating, I don't think that the thermostat is the problem. __________________ [COLOR=SandyBrown] 1994 YJ 4.0 H.O. 3-speed Auto[/COLOR] My NEW [url="http://www.rigrater.com"]RigRater[/url] Score: 406RRv1.0 with a BOA of 31.60

02-25-2005, 02:13 PM	#7
youngjeeper11 Registered User Join Date: Jul 2004 Location: pennsylvania Posts: 642 Profile Gallery Classifieds My Jeeps	mine is still blowing, just not hot, and I definityl have anitfreeze, beacuse that was the first thing i checked, the resivoir is only 3/4 of the way full though. __________________ Jeep 1:Used to have a 93 YJ 2.5l- 3.5" Black Diamond, Chevy TBI 5.7l V8, SM 465 4 speed, 8.8 rear( 4.10, L/S), rhinoline, Mile Marker 9000, NP 231, Had to sell it due to college Jeep 2: 89/91 YJ, 4BT Cummins, NV4500, NP 231, Old Man Emu 2.5" suspension lift, 1" body lift.....Runs and drives, but very much a project Interned at Novak Conversions 2 summers ago

02-25-2005, 03:53 PM	#9
youngjeeper11 Registered User Join Date: Jul 2004 Location: pennsylvania Posts: 642 Profile Gallery Classifieds My Jeeps	also, what excactly does the thermostat look like? is it just a little sensor thing with 2 wires coming out? __________________ Jeep 1:Used to have a 93 YJ 2.5l- 3.5" Black Diamond, Chevy TBI 5.7l V8, SM 465 4 speed, 8.8 rear( 4.10, L/S), rhinoline, Mile Marker 9000, NP 231, Had to sell it due to college Jeep 2: 89/91 YJ, 4BT Cummins, NV4500, NP 231, Old Man Emu 2.5" suspension lift, 1" body lift.....Runs and drives, but very much a project Interned at Novak Conversions 2 summers ago

02-25-2005, 05:43 PM	#13
youngjeeper11 Registered User Join Date: Jul 2004 Location: pennsylvania Posts: 642 Profile Gallery Classifieds My Jeeps	the engine warms up, but hot air doesn not come out at all, even after 30 minutes of driving. so what next? now that you mention it, it hasnt worked since I flushed the antifreeze, so if there is air in there, how do I get it out? __________________ Jeep 1:Used to have a 93 YJ 2.5l- 3.5" Black Diamond, Chevy TBI 5.7l V8, SM 465 4 speed, 8.8 rear( 4.10, L/S), rhinoline, Mile Marker 9000, NP 231, Had to sell it due to college Jeep 2: 89/91 YJ, 4BT Cummins, NV4500, NP 231, Old Man Emu 2.5" suspension lift, 1" body lift.....Runs and drives, but very much a project Interned at Novak Conversions 2 summers ago

02-24-2005, 08:19 PM	#2
rockjock Registered User Join Date: Jan 2004 Posts: 49 Profile Gallery Classifieds My Jeeps	Well tell us a little more. Did it stop blowing? Is it just not blowing hot? Where you moving the temp slide thing? Where there any symptoms leading up to the problem? Cheers RJ

02-25-2005, 04:45 PM	#11
rhinoss Registered User Join Date: Oct 2004 Location: Lenexa, KS Posts: 866 Profile Gallery Classifieds My Jeeps	To test the thermostat if you'd like, although if it's suspect I typically replace it anyway. To test it, you can heat it up by dropping it in boiling water to see if the plunger opens up. What happens if you leave the jeep idling for 10 to 15 minutes. Does the heater heat up at all?

02-25-2005, 04:58 PM	#12
pyro9862 Registered User Join Date: Mar 2004 Location: Long Island, NY Posts: 1,563 Profile Gallery Classifieds My Jeeps	Ok, it's blowning cold air, you have antifreeze. Next questions. Did you do anything at all when it stopped working, flush the antifreeze, etc? It is possible to have air in the system keeping it from getting water to some places. Next what does your temp guage say, is the coolent warming up? If the coolent isn't warming up then we start looking at a stuck thermostat. If it is start looking at the heating system.

02-26-2005, 01:35 PM	#15
dcafaro Registered User Join Date: Dec 2003 Posts: 771 Profile Gallery Classifieds My Jeeps	Just solved the same exact problem. Here is how I resolved the issue. Let the Jeep get to operating temp and make sure your gauge is registering. It probably won't get to 100% operating temp on the gauge but as long as something registers. If gauge reads proceed. Check all hoses and make sure you're getting fluid through them by simply squeezing them. At this same time get an idea if they are warm hot cold etc. I would start with the upper and work your way back. The upper hose should be hot and sometimes pressurized. Then go to the the smaller hose to the right coming of the t-stat housing (WATCH YOUR FINGERS AND HANDS AROUND THE FAN, IT STICKS OUT MUCH FURTHER THAN THE EYE CAN SEE!!!!!) IT should be at least warm and it travels into the manifold (I think). From there your lower heater core hose comes out of the manifold and over to the heater core fitting near the battery, this should be hot. Then check the upper heater core hose, it to should be at least very warm, but less than hot, (the coolant has traveled through the core and has cooled some so it won't be as hot as it was going in). This hose goes into the water pump. Finally check your lower heater hose and be very careful as before or even turn the engine off at this point. Again it should be warm but not hot as fluid has traveled throught the radiator and cooled. If the hose going into the core is hot but the one coming out is much cooler then your core is shot and you need to replace it, which was the case with mine (it's not really that big of a project, the air box comes out easy but it takes a bit to line everything back up to reinstall it If the there is no warm fluid passing through the smaller hose coming out of the t-stat to the right then I think your t-stat is shot (however if you get to normal operating temp without overheating your t-stat is fine.) Also check your pump, at the top under the t-stat housing, check to see if you have fluid dripping. Your pump housing has a weep hole in it and will drip when the pump is starting to fail.