FJ60 heater question

[SAsh]

I'm sure this has already been asked and answered, but a lot of threads and unable to find one. My front heater does not blow hot, but the rear one gets a little warm.
I have burped the system and it does have plenty of coolant. I have not flushed mainly because it has been in the single digits. The heater valve on the firewall does moves up and down. The hoses going into and out of the valve does not feel like it has any pressure on them. This is with the heater on and with it off. So I'm stumped and asking you all for some guidance. Oh and the temp gauge does not get off of C while the cruiser is moving not sure if that will help or not.

 

[norsk]

did it work before?

sounds like the front core is plugged or the hose to it is.

I would drain fluids, then remove hoses to main, and then see if you can pump water (liquid not frozen) thru the core, or air.

Have to test each part of the system to gather information on where it is failing

dougbert

 

[Slow Left]

Did you recently do work on the thermostat? If you forget to put the ring gasket on (it sits on top of the thermostat, inside the housing) then coolant can move around the thermostat and the thermostat can't 'close'. This means that the whole system will run cool and not get up to operating temperature.
Just a thought.

 

[klinetime574]

The temperature gauge not moving off of "C" is usually related to a stuck open or absent thermostat.

Do you have a thermostat installed?

No thermostat, and you're never reaching operating temperature which the heater core needs to make heat.

 

[Slow Left]

Yeah, if the temperature sending unit was not working properly (therefor not sending the correct temperature reading to your gauge) but the engine was warming up properly, then I'd say you should check either the sending unit itself or the wire. The wires get really brittle because of the heat on the top of the engine.

But, since both your gauge and heater are telling you that the truck isn't warming up to operating temperature, that kinda points to your thermostat.

 

[SAsh]

This is the first full winter that I have owned this cruiser, so not sure if it was working before. When the outside temps are above freezing the temp gauge does move off of C, but it does take a while. I will change the thermostat and check the front core. I will keep you all posted thank you for the advise.

 

[klinetime574]

As Slow Left points out in post #3 of this thread, don't forget the O-ring on top of the thermostat. This allows for a proper seal. Without it fluid will go around the thermostat.

If you open it up and you have a thermostat... I would change it

 

[SAsh]

Awesome thanks fellow cruisers, but a follow up information. I tried running the heater last night while looking at Christmas light and I noticed a spike in volts. It would not last but maybe 30 seconds then stop. This went on for a while until I finally made home. Would the heater have anything to do with this, or do I have another issue to deal with.
I'm going to clean all the terminals tonight and hopefully put a new thermostat in as well. Am I on the right track.

 

[Slow Left]

I tried running the heater last night while looking at Christmas light and I noticed a spike in volts. It would not last but maybe 30 seconds then stop.

What do you mean by voltage spike? What voltage/where were you reading it from?

Maybe you drove just a little too close to all those crazy christmas lights? No, I know, this isn't the problem, but I had to put it in there given the circumstances...

 

[SAsh]

Funny, no the lights got real bright and the gauge maxed out.

 

[Slow Left]

If it is the gauge on the instrument panel cluster that measures voltage, that is the voltage at which your alternator is charging the battery while the engine is running.

I'm not sure if, while the engine is running, components such as lights, heater, radio, etc. run directly from the alternator or whether the alternator charges the battery and they run from the battery. I don't have experience fixing that problem, so you're better off following someone else's advice on this one.

 

[SAsh]

Well thanks anyways Slow Left. I'm pretty sure it's the battery going bad, but still open to any ideas anyone might have.

 

[Slow Left]

Yeah, no worries. You know you should be able to take the rig to an aftermarket autoshop and have both the battery and the alternator tested. Ask before you take them out, it might be free. Pretty easy to pull those in the parking lot and walk them inside, if they tell you you have to have them off the vehicle for testing. Might call a couple of local shops to see if they do this. Like Sears, even.

 

[Zack1978]

My 2 cents......
I have been chasing hotter heat from the main (front) heater for the past 13 years in my 1987 FJ60. The thermostat has been changed, the needed gaskets are there, the heater core has been flushed, and on and on and on.
All I can say is that the main heater is kinda/sorta adequate, but it never seems to get really hot; luke warm or a touch better may be a good description. The rear under seat heater on the other hand is simply amazing. The air from the rear heater will burn your hand it is so hot. You may be able to bake cookies with that heat. I think it just may be an FJ60 thing to have poor heat IMHO.


Zack

 

[jawjatek]

Its not too cold in N Ga, maybe upper 20s low tonight, but my "87 FJ60 heater kicks ass and will run you out of the truck on high. I just bring it up halfway and its fine there. Rear heater is not needed and I want that space for my HAM radio sys unit, so out it came.

When I first got the truck, I did a flush and fill, then later had to take out the thermo housing during de-smog 'cause I stripped a bolt, so I checked the t-stat while I was in there. I tested the orig T-stat in a pot of water over heat with a Fluke thermo probe in there and it tested fine, so I put it back in the truck using the 2 new Toyota t-stat gaskets. The hoses were old (original) and I replaced some of them.

I tried filling it with the front uphill, but it wouldn't burp, got hot and was blowing steam. So I tried something else and ended up doing it my way: I open one of the water hoses (I forget which one and will have to verify), and it lets the air out and the block filled right up. Then I start the truck and warm it up with heater on high, and top off after the t-stat opens and its flowing well. I also fill it with the front lower than the rear, opposite of the consensus here, strangely. It worked well for me. YMMV. Temp gauge comes to about 1/3 the way up when fully warmed up.

Anyway the heater works like a champ since then. Maybe a good flush will get the flow going, also check the control valve?

 

[rmblaire]

My temp gauge never moved either and the result was a Luke warm heater. I did the thermostat tear down, new water pump, new radiator and all new hoses. End result, a nice big piece of cardboard in front of the radiator all winter long. Temp gauge hangs right in the middle and heater is awesome.

 

[gregnash]

I am thinking there must be a clogg somewhere because I have similar problems.
Last spring I had my temp gauge stop working, opened up the t-stat to see that the top o-ring was blown but had already purchased a new t-stat so I replaced (along with multiple hoses). Before, when it was working, I would get NUCLEUR hot air coming out of the front heater if I left the truck warming up for a good 15 minutes with the heater on high. Wife loved it!

Now after replacing it and multiple hoses, it gets warm but not as hot as it used to. So am I correct in thinking that there is a clog somewhere that is causing issues? Thermostat was replaced with the same 180* one (I believe) so that should not play a role in it, and the rear heater is still super hot. Oh and temp gauge works fine, she goes up to about 1/3 way and 1/2 when she is really warm but never any further.

 

[Elbert]

if the top "o-ring" or rubber washer is missing or wore out...the thermostat function is not going to work properly and most likely the truck will be running rather cold in the winter time, which obviously impacts the heat.

Make sure the heater pipes that feed the rear heater are in good shape and they are warm once the the truck warms up.... Replace the thermostat, and both related gaskets and confirm the heater control valve on the firewall in the engine compartment works...and make sure you are full of coolant and have no leaks. After that both heaters should work and I would think provide adequate heat for most any situation.

 

[SAsh]

Up-date: I had the system flushed, and that made it a little better. My mechanic told the thermostat was stuck open. So when I went to install the new one. I found the old one was in upside down, and the o-ring was nowhere tone found.

 

[Slow Left]

Cool. Glad you got that sorted out.

What about the voltage spike problem? Did you figure out what that problem was?

There has been a recent thread or two about voltage regulators on 60 alternators. You might want to check this link out:
https://forum.ih8mud.com/60-series-wagons/791031-voltage-regulator.html

Maybe a local auto parts store could test the voltage regulator too, if they can test the alternator...