FZJ80; NO HEAT (1 Viewer)

[Aquafink]

Just bought a '97 80.
Heat blows cold.
Front heater core flushed and clear.
Coolant level OK.
Temp valve opening.
I noticed that there is zero pressure on the inlet hose( driver's side) when engine is running.
Then I noticed that when I pressurized the radiator with a garden hose water blasted out of that driver's side hose.
Shouldn't there be pressure at that inlet hose while engine is running?
Any info would be helpful!
Thank you

 

[ajax1]

Does rear heat work?

 

[taylort232]

Check heater valve on top of the engine compartment (all the way up top, above the throttle cable connectors). Make sure that opens.

Make sure you burped the coolant. Mine takes around 5-10 minutes of burping before the heater blows hot.

 

[Kernal]

Which hose leaked after pressurizing the cooling system? Any water leaking inside the vehicle, front foot-wells, carpet wet??

There is a high risk of rupturing components in the cooling system using a garden hose as the pressure in a residential water connection is many times the max pressure of the system.

 

[ZackR]

As @Kernal said go easy on the pressure when testing.

Depending on your water pressure the garden hose could be 30-80psi which is way too much.

 

[Mark W]

Just bought a '97 80.
Heat blows cold.
Front heater core flushed and clear.

Core flushed how/with what? Determined to be clear how?

Mark...

 

[Aquafink]

Does rear heat work?

No.

 

[Aquafink]

Check heater valve on top of the engine compartment (all the way up top, above the throttle cable connectors). Make sure that opens.

Make sure you burped the coolant. Mine takes around 5-10 minutes of burping before the heater blows hot.

How much of an angle must the truck be on for burping to be effective?
Thanks.

 

[Aquafink]

Which hose leaked after pressurizing the cooling system? Any water leaking inside the vehicle, front foot-wells, carpet wet??

There is a high risk of rupturing components in the cooling system using a garden hose as the pressure in a residential water connection is many times the max pressure of the system.

I disconnected the driver's side rubber pipe that attached to the heater control valve.
Does the water for the heat originate at the thermostat and run through that metal pipe rearward? Thanks.

 

[Aquafink]

I disconnected the driver's side rubber pipe that attached to the heater control valve.
Does the water for the heat originate at the thermostat and run through that metal pipe rearward? Thanks.

No water getting into cabin.

 

[taylort232]

How much of an angle must the truck be on for burping to be effective?
Thanks.

I put in just on a small incline on my driveway. I think 6" from front to back would do it.

 

[Aquafink]

I put in just on a small incline on my driveway. I think 6" from front to back would do it.

Thanks. I'll try that.

 

[taylort232]

I disconnected the driver's side rubber pipe that attached to the heater control valve.
Does the water for the heat originate at the thermostat and run through that metal pipe rearward? Thanks.

Hot water goes from the drivers side to the passenger side through the heater control valve

If you disconnected water into the valve then that’s your problem

 

[Aquafink]

Hot water goes from the drivers side to the passenger side through the heater control valve

If you disconnected water into the valve then that’s your problem

Thanks.
I disconnected the inlet pipe and return pipe, added a clear plastic tube between the two, and with the coolant level full and engine running, there is no water flow.
I'm thinking after about 8 hours of core clean- outs and rear heat unit removal and cleaning that my problem might be a thermostat or water pump problem.
Thanks for your input.

 

[taylort232]

Man if there's no water going through there at all, I don't think that can be a thermostat problem. Are you sure it's not capped off somewhere? I think the inlet side of that control valve comes down behind the motor near the PHH and another connection to the block.

When I accidentally left my control valve hose loose after replacing it last year, coolant squirted all over the place on a cold start.

 

[Aquafink]

Man if there's no water going through there at all, I don't think that can be a thermostat problem. Are you sure it's not capped off somewhere? I think the inlet side of that control valve comes down behind the motor near the PHH and another connection to the block.

When I accidentally left my control valve hose loose after replacing it last year, coolant squirted all over the place on a cold start.

When I put the garden hose in the open radiator when it running( just started) and the driver's side inlet pipe is off the valve, I can see coolant gush out so I know it's not clogged. Got a new water pump coming and have read radiator cap might need tabs bent more to insure pressure. Driving me nutso!!

 

[Aquafink]

Does rear heat work?

Solved the problem. Water pump impellor was shot. New water pump got it circulating and heat blows ht now!

 

[Aquafink]

When I put the garden hose in the open radiator when it running( just started) and the driver's side inlet pipe is off the valve, I can see coolant gush out so I know it's not clogged. Got a new water pump coming and have read radiator cap might need tabs bent more to insure pressure. Driving me nutso!!

Water pump was shot. Blasts hot air now!

 

[Aquafink]

No water getting into cabin.

Water pump impellor was bout gone. New water pump has her blasting hot air!! Thanks for the help.

 

[Irish Reiver]

That must be a first. Metal impeller on metal shaft. How does that just fail? Did you have some cheap aftermarket pump or was the cooling system filled with pure water which was allowed to freeze?