• PLEASE READ >>> Accounts Security Locked

    The link above goes to a thread in the Announcements - Help - Testing section of the forum....you are welcome to follow normal menu structure and find it there. ~woody

FJ80 heater woes. Need help too.

Joined
Feb 12, 2005
Messages
806
Location
Hollister, CA
Hey guys,

My cruisers heater does not seem to be getting hot enough. The truck had its radiator serviced not too long ago. It heats up fine, the temp guage reaches normal operating temp. but still no heat coming from vents even when its set to very hot.

Want to find out quick what is going on so I can fix it. Its like an icebox riding in this thing.

Any help, input or suggestions would be great.

thanks
 
Joined
Jun 16, 2003
Messages
1,802
Make sure heater valve is opening up. If so, then flush the heater cores.
 

e9999

Gotta get outta here...
Moderator
Joined
Sep 20, 2003
Messages
17,686
Location
US
you should be able to see the valve moving under the hood if you have somebody wiggle the temp control. (Needs the key on IIRC). Well, at least on my 97.
 
Joined
Sep 15, 2004
Messages
2,174
Location
Western Slope, CO
As e9999 and Rich said, this is the valve for an FJ80.

See the cable that is under the valve. That cable hooks up to the cool/hot level on the dash.
DSCF0943.JPG
 

e9999

Gotta get outta here...
Moderator
Joined
Sep 20, 2003
Messages
17,686
Location
US
DigitalKnight86 said:
I just have to make sure that cable is doing its thing?

as a start!

later you get to cut sheetmetal, weld, grind, and hammer wildly.... :D
 
Joined
Sep 15, 2004
Messages
2,174
Location
Western Slope, CO
If you warm the rig to op. temp, can you feel a temp difference in between the two lines going to/from the heater core? What about the secondary heater under the passengers seat.
Do you have pressure in the cooling system?

Checked the FSM for ya, I did not see a 'flushing the system' in the cooling section.
 
Joined
Sep 15, 2004
Messages
2,174
Location
Western Slope, CO
DigitalKnight86 said:
Hey guys,

My cruisers heater does not seem to be getting hot enough.
thanks

Now that I reread the first line, I thought back to something that happen to me.
My thermostat was broken in two pieces thus no preassure in the system. No pressure means to raising of the boiling point for the cooling system. I replaced my water pump, thermo and gaskets and the system was back to normal.
 
Joined
Feb 12, 2005
Messages
806
Location
Hollister, CA
I don't think there is anything wrong with the thermostat. Could there just be something wrong with the valve internally? I'll heat it up and see if there are temp differences between the two lines and I'll check under the passengers's seat as well. I'll let you know what I find.
 
Joined
Jun 16, 2003
Messages
1,802
Most likely the heater cores are clogged. To flush them find the inlets and outlets. The inlets connect to the heater valve. Get appropriately sized barbed garden hose adaptors and hook your garden hose to the heater core outlet. Hook up a drain hose to the inlets so you don't flood your engine compartment. Turn on the garden hose and flush 'em out. Will work best if you flush each heater core seperately. That's all there is to it.
 

e9999

Gotta get outta here...
Moderator
Joined
Sep 20, 2003
Messages
17,686
Location
US
you can try my writeup in the FAQ although that is for an FZJ
 
Joined
Feb 12, 2005
Messages
806
Location
Hollister, CA
I'll try that. Are the heater cores basically the same on all 80 series?

If anyone out there with a FJ80 has done this, please show me the way.
 
Joined
Sep 15, 2004
Messages
2,174
Location
Western Slope, CO
Heater Core

DK-
This is what the heater core looks like. I am pretty sure the cores are all the same for FJ and FZJ's. But if I'm wrong someone will correct me.

If you can notice the two hoses that go into the firewall about six inches below the valve, these are the hoses that supply/return the coolant to the heater core.

You should be able to take the hose off one end and put a garden hose to it. Disconnect the other end for purging the core.

Don't be surprised if you have to buy new hoses or clamps later.

Help this helps.
Heater Core - Core unit damage.jpg
 
Last edited:
Joined
Feb 12, 2005
Messages
806
Location
Hollister, CA
Okay, today I flushed the heater core like its describes on e9999's write up. The air is still coming out cold even with the truck on normal operating temp and heater turned all the way up.

Need to fix this really soon as it is cold in there.
 
Joined
Jun 16, 2003
Messages
1,802
Make sure the heater valve is fully open. If it appears to be open but you are not getting heat, then remove the valve and examine it internally, verifying that is does open. You can always replace the valve with a short piece of straight pipe, as a test, to verify the valve is not the culprit.

If the valve is operational and open, and the heater cores are clear, having been flushed, but you still have no heat, then logic would suggest you have a blockage upstream or downstream of where you have flushed.

You were able to get a good flow through the heater cores with the garden hose, right?
 
Joined
Feb 12, 2005
Messages
806
Location
Hollister, CA
The flow with the garden hose was great, rinsed it out for almost 2 minutes on full blast. I'll check the valve tomorrow to see if it is opening up internally.
 

Users who are viewing this thread

Top Bottom