DieselDaze

'97 xj 4.0

I've flushed the upper and lower hoses to the heater core seemed to flow freely from the pressure with a garden hose.. I was trying to drain the radiator but nothing comes out when I turn the drain plug, I'll assume its clogged up as it appears "stop leak" may have been used from PO as I see some residue sparkles..

since the actual hose doesn't start til midway up the radiator do you think its okay for now that the bottom radiator is clogged?? or is it possible it could still place a small role in me not getting any heat in the cab..??

If its 45-50* out I can get a little warmth from the heater after the engine warms up forever but nothing substantial and winters creeping up...

I read a few archived threads but wanted to bring other ideas into my mix,

what can I do to try to get heat??

djb383

The heater should work with no flow thru the rad....the heater is in the "bypass" coolant loop, not the "rad" coolant loop. If coolant flow thru the heater core is good, both heater hoses should be very hot to touch when coolant is up to operating temp. Have u also checked the heater temp control cable under the dash?.....it moves/controls the heater blend door. Have u checked for a t-stat?.....it could be missing or stuck open. No telling what POs have done.

DieselDaze

no I'm embarrassed to say I haven't... I will go out and check it after dinner in a bit.. is there something specific I should be looking for??

djb383

U'll need a flashlight and get under the dash to check the heater temp cable operation (passenger side, I believe). U'll need to remove the t-stat cover to check for a t-stat.

scottmphoto

On a few different vehicles that I've had in the past, the rad was clogged and wouldn't drain when I got them from the PO. Close everything up and start the vehicle. let it get warm then carefully open the drain. The pressure "should" clear the blockage at the drain. I have done this several times and it has worked for me. Just be careful and don't scald yourself. If it doesn't clear the blockage fairly easily, you may need to take it to a shop or just replace it.

DieselDaze

checked the cable and it appears to operate fine. I will check the t-stat tomorrow and report..

djb383

If its the OE style rad, the drain plug is plastic, very fragile and breaks easily. Drain/flush the rad by removing rad hoses at the stat cover and water pump.

DieselDaze

okay sure enough there was no thermostat !! amazing it never overheated during the summer !! had it out wheeling with the a/c on and it was just a touch over 210*...

I love it here !!! Thanks DJ, this is what makes this community so awesome, although I should have thought 'thermostat' I honestly didn't even consider it and was determined it just had to be something more complicated, and because it never overheated last summer probably kept my thoughts at bay from it being the culprit..

I'm heading to get a thermostat now.... and I'm almost positive I will have heat next time I need it..

djb383

FWIW, a properly functioning t-stat does one thing only.....control minimum coolant temp. The other cooling system components, along with driving conditions, determine max coolant temp.

Tulsa, OK.....a beautiful town.....saw a live Tommy Emmanuel concert there about 4-5 years ago.

DieselDaze

BOOM !!!!

and there was heat ....

now if we could only get a good freeze here so I can test it against the elements ...

suppose to stay pretty decent until next week sometime...