heat doesnt seem warm enough

RH31379 · 12-10-2007, 09:59 AM

The heat on my 88 YJ, 4.2, automatic doesnt seem warm enough. The temp gauge is showing 210 +/-. the heat gets warm then seems to cool down. new water pump and t- stat. Heater core??

also... on my 87 YJ 4.2 5 speed
the temperature gauge will work then not work for a few days and work again, the fuel gauge did the same the other day, went out and the temp started working then they both worked again and then the temp stopped and started again. I know the cj's are tied together, are the yj's? or just my luck. any suggestion on what to check?

NewhampshireYJ · 12-10-2007, 10:47 AM

Is your heat turning all the way to WARM? Your cables could be stuck causing the heater door to not fully open. This happened on my jeep and i just followed the cable and used my hand to push the door fully open and after that my heat has been HOTTTTTTTTTTT.

RH31379 · 12-10-2007, 11:26 AM

it's just the one pivot? i believe it is going all the way.

jaw41272 · 12-10-2007, 11:34 AM

My heat will melt the soles of your shoes, sounds like your heater control cables aren't woking properly like newhamp said

NewhampshireYJ · 12-10-2007, 01:47 PM

Quote:

Originally Posted by RH31379

it's just the one pivot? i believe it is going all the way.

Its the one pivot but you need to make sure its pushed all the way to the driver side. So the little bar that sticks out should be down the bottom. I thought mine stopped but i figure it out after i pushed hard enough it could toward driver seat and that made my heat hotter.

RH31379 · 12-10-2007, 02:05 PM

I'll check it out, what would be the symptoms of a bad heater core?

NewhampshireYJ · 12-10-2007, 03:40 PM

Quote:

Originally Posted by RH31379

I'll check it out, what would be the symptoms of a bad heater core?

The heater core is made up of small piping that has numerous bends. Clogging of the piping may occur if the coolant system is not flushed or if the coolant is not changed regularly. If clogging occurs the heater core will not work properly. If coolant flow is restricted, heating capacity will be reduced or even lost altogether if the heater core becomes blocked. Control valves may also clog or get stuck.

Also check to see if theres pressure in the hoses to make sure the t stat is working properly.

will_982 · 12-10-2007, 03:46 PM

I'd check the coolant level also, if it's low it never makes it to the heater core.

roadhog481 · 10-22-2009, 10:20 PM

Iknow this is a really old post but i just did this procedure and it worked very well.
My symptoms were heater not blowing very hot, and when i did turn the heat up it would blow warm for a second and then cool down really fast. I replaced the thermostat and flushed the cooling system that had been running rusty water for years(not me, previous owner). filled it with a 60/40 mix and Still no joy on the heater.
so i disconnected both heater hoses, snipped off about 2 inches and squeezed the end of the heater hose into the garden hose.
turn on the water slowly and you should get rust and crap coming out of the other hose. then reverse the flow. back and forth until full flow is observed at the other hose. I had it run gloppy rusty crap run for a couple seconds.

note: watch the pressure from the garden hose it might be too high for the core and blow a hole in it.(then again im not an expert)

finally, hook all hoses back up and enjoy the hair cinging hotness.

hope this helps

Daryl

**timatoe** · 10-22-2009, 11:22 PM

Take a look through here.... http://www.jeepforum.com/forum/f12/better-yj-heat-thread-roundup-503604/

**Que89YJ** · 10-23-2009, 06:56 AM

Heat in Florida??? What for???? LOL

10-22-2009, 10:20 PM	#9
roadhog481 Registered User Join Date: Oct 2009 Location: Florida, Wa Posts: 5 Profile Gallery Classifieds My Jeeps	Iknow this is a really old post but i just did this procedure and it worked very well. My symptoms were heater not blowing very hot, and when i did turn the heat up it would blow warm for a second and then cool down really fast. I replaced the thermostat and flushed the cooling system that had been running rusty water for years(not me, previous owner). filled it with a 60/40 mix and Still no joy on the heater. so i disconnected both heater hoses, snipped off about 2 inches and squeezed the end of the heater hose into the garden hose. turn on the water slowly and you should get rust and crap coming out of the other hose. then reverse the flow. back and forth until full flow is observed at the other hose. I had it run gloppy rusty crap run for a couple seconds. note: watch the pressure from the garden hose it might be too high for the core and blow a hole in it.(then again im not an expert) finally, hook all hoses back up and enjoy the hair cinging hotness. hope this helps Daryl