How hot should my heater be?

[jpjeep26uk]

Recurring theme from me so please forgive the repeat question.....

Now we are getting colder here in the UK, the heating never seems to get seriously hot in the cab.
I installed a new core exchange in the heating box and totally cleaned up the whole box and reinstalled it.
It does blow 'warm' air and the levers and flaps are all working properly, but it never gets 'proper' hot air.
The pipes into the exchange are piping hot, but the ones coming out are not so hot.

I also noticed I'm constantly topping up the reservoir tank. I burped the car on a slope and there's no bubbles coming out.
I squeeze the top rad hose and near the rad end it's almost too hot to touch after a good run. But the other end that goes down to (or from?) the thermostat is much lower in temp.
I've done a leak test and can't find any leaks anywhere but she is definitely using coolant up and I wonder if it's related to me not getting decent heat in the cab?

Any suggestions?

Thanks

 

[dieselearl]

nice job on cleanup. have you taken a chemo gun and test the stat or heat from inside, maybe some air still in line or bad stat.

 

[dieselearl]

got a little fast on spelling/ it should be therm gun/sorry about that.

 

[jpjeep26uk]

nice job on cleanup. have you taken a chemo gun and test the stat or heat from inside, maybe some air still in line or bad stat.

Hi Earl, thanks, the housing is now spotless inside and out. it was disgraceful! No not tried that. I will see if i can borrow a temp gun and give it a go. Should i be looking for something obvious and specific? Thanks.

 

[jpjeep26uk]

got a little fast on spelling/ it should be therm gun/sorry about that.

no worries sir, I just ordered one from amazon...I'll take measurements and report back when it arrives.

 

[jpjeep26uk]

nice job on cleanup. have you taken a chemo gun and test the stat or heat from inside, maybe some air still in line or bad stat.

Hi, got the thermogun and fired away...
10 mile spirited drive in 4th to get it fully warmed up:

Engine running gives;
Block reads 195
Airvent in cab reads 30
Top hose at rad end reads 120
Top hose at stat end reads 105
Inlets read 170
Rad cap 102
Temp gauge reads below 210
Exhaust at block reads 358

Are these decent temps?
It's 8deg here.

Thanks

 

[machoheadgames]

What temps do you get on the lower radiator hose? I wonder if you have the wrong water pump installed or one with a backwards impeller.

The upper radiator hose is where coolant comes into be cooled, so to be cooler at the thermostat end than the rad end sounds backwards and like maybe the wrong water pump is sending things the wrong direction, and as such, the heater is not getting correct coolant flow.

 

[dieselearl]

not sure what all the numbers should read, temp gauge 210 look good. back in Oct you were having a problem with heater, bled the air out and you started getting good heat. with all the clean up work you done recently i wondering if you got air in there again? what degree stat are you using? it just my wild guess but the inlet reading of 170 just coming out of motor seems a bit low?

 

[Plastic Fury]

YJ's are known for having nuclear heat lol. Mine sure does. On cold days (cold for central FL), I can run the heat with no top or anything and it keeps my feet plenty warm. That being said, I completely rebuilt my cooling system when I rebuilt this Jeep after I bought it. I cleaned out ALL the sludge from inside the engine, replaced all the crusty hoses that were lined with rust, new radiator, new heater core, new water pump and new t-stat. Properly bled the system with new coolant/distilled water. The heater core was so full of sediment, it was damn heavy compared to the new one I installed.

As Macho mentioned, do you have the correct direction water pump installed? Which thermostat did you use?

 

[jpjeep26uk]

What temps do you get on the lower radiator hose? I wonder if you have the wrong water pump installed or one with a backwards impeller.

The upper radiator hose is where coolant comes into be cooled, so to be cooler at the thermostat end than the rad end sounds backwards and like maybe the wrong water pump is sending things the wrong direction, and as such, the heater is not getting correct coolant flow.

I'll redo the temps in daylight today and try to get better solid readings. I'll do the lower pipe too.
The pump was replaced in early 2022 by the PO and was definitely the right one as the paperwork shows it as a replacement for a wrong one fitted a week before.

I don't know what stat was put in. Guess I could replace it anyways and then ge sure it's a 195er?

 

[jpjeep26uk]

YJ's are known for having nuclear heat lol. Mine sure does. On cold days (cold for central FL), I can run the heat with no top or anything and it keeps my feet plenty warm. That being said, I completely rebuilt my cooling system when I rebuilt this Jeep after I bought it. I cleaned out ALL the sludge from inside the engine, replaced all the crusty hoses that were lined with rust, new radiator, new heater core, new water pump and new t-stat. Properly bled the system with new coolant/distilled water. The heater core was so full of sediment, it was damn heavy compared to the new one I installed.

As Macho mentioned, do you have the correct direction water pump installed? Which thermostat did you use?

Nuclear? Haha. I wish. Nah. Mine is warm but not super hot. I did do a decent flush when I reconditioned the housing and put a new core in. Totally flushed the system every which way and a crap load of sludge and pink chalky stuff came out. Maybe something got left behind and is now blocking the system a bit. I'll do a reflush and start again today.
The stat was done by my garage bloke so I don't know but he's one of the UKs top YJ fixer so I'm sure it was right. Pump was put in before my time but I'm assured its the right one.

 

[GoFundMe?]

Was anyone talking thermostat? I just want to get my fan going! Too many jobs around house and stupid holiday.

 

[PBG]

It sounds to me like the temostat isn't opening or at east not all the way . If the top hose is hot and the gauge is reading like 190 the bottom hose should feel the same as the top, if the bottom hose feels not as warm or cool then you need to replace the termostat.

 

[GoFundMe?]

It sounds to me like the temostat isn't opening or at east not all the way . If the top hose is hot and the gauge is reading like 190 the bottom hose should feel the same as the top, if the bottom hose feels not as warm or cool then you need to replace the termostat.

Seems obvious but didn’t see any troubleshooting. Stick it in a pan on stove?

 

[machoheadgames]

It sounds to me like the temostat isn't opening or at east not all the way . If the top hose is hot and the gauge is reading like 190 the bottom hose should feel the same as the top, if the bottom hose feels not as warm or cool then you need to replace the termostat.

The heater should get hot regardless of thermostat status. And when cooling properly, Lower radiator hose should be warm but not really hot because the radiator should have removed much of the heat.

 

[Flyer58]

I've probably changed five T-stats in my life because they stuck - wide open. I've never had one fail in the closed position. For me, the first indication was the heat and engine temp gauge was very slow to rise and never any over heating.

 

[TimberTim]

thought I'd mention, when I look for coolant leaks I attach a bicycle tire pump to the radiator over flow hose and put 10# of pressure in the system so I can work on a cool engine

 

[TimberTim]

I've probably changed five T-stats in my life because they stuck - wide open. I've never had one fail in the closed position. For me, the first indication was the heat and engine temp gauge was very slow to rise and never any over heating.

lol I had a 72 390 F250 .... when the heater started blowing cold air it was time to put water in the radiator lol

 

[GoFundMe?]

I've probably changed five T-stats in my life because they stuck - wide open. I've never had one fail in the closed position. For me, the first indication was the heat and engine temp gauge was very slow to rise and never any over heating.

When setting long periods

I've probably changed five T-stats in my life because they stuck - wide open. I've never had one fail in the closed position. For me, the first indication was the heat and engine temp gauge was very slow to rise and never any over heating.

lol I had a 72 390 F250 .... when the heater started blowing cold air it was time to put water in the radiator lol

Much less common but happens, sometimes setting long time with corrosion. Worth taking out and testing or replacing.

 

[GoFundMe?]

I've probably changed five T-stats in my life because they stuck - wide open. I've never had one fail in the closed position. For me, the first indication was the heat and engine temp gauge was very slow to rise and never any over heating.

Reread post and he is losing coolant somewhere. Tailpipe steaming, smelling? At least change thermostat, flush radiator and engine.