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No Heat

OSUBauer

NAXJA Forum User
Location
Tulsa, OK
Last weekend my water pump went out. I replaced the WP, T-stat, belt and burped the system. This morning I turned the heater on and all I got was ice cold air. Engine operating temp was normal at about 195. Any thoughts?

By the way, it's a 93 but I don't think that matters.
 
Double check you reconnected the vacuum line to the valve that controls the coolant to the heater core. The valve redirects water back to the motor when the heat is off, it opens and directs the coolant flow thru the heater core when you turn the heat on. If you dislodged the vacuum line on that, it won't let warm water into the heater core.
 
I've had pretty good luck getting the air to move into the top of the radiator, where it can be purged into the coolant recovery tank, by squeezing the top radiator hose flat with two hands. Repeat a few times with the motor running. Eventually you will feel the top hose get a little harder to squeeze.
I turn the heater on before I do this, I don't really know if it helps or not, but it seems prudent.
Another trick I use is an old weak radiator cap. I have one that only holds about 7 PSI, this really helps to purge the air. When the air is gone, I switch back to the good 16 PSI cap.
Before the motor gets really hot, just after the thermostat starts to open some. I loosen the cap a little (with a glove on) and allow it to surge and leak out a little to let the majority of the air out. Squeeze the top hose a few times and loosen the cap again (just enough to release the pressure). Put a catch pan under the radiator and rinse out the area under the air box with clean water. For the next two or three motor hot, cool down cycles I usually have to add a little coolant to the coolant recovery tank.
I've had few air blockage problems using this method. I do almost the same with the Renix, it helps move the air to the surge tank quick.
 
All I do is stand there with a cup of coffee and a smoke, keeping the dog leg filler up to the edge and watch the coolant, the air escapes as it passes and with air the coolant looks like fizzy green soda. I just keep at it for 20 or so minutes till all the fizzies are gone. The air does not like being mixed in with that coolant, nor more than co2 likes being mixed in with soda, you just don't want to collect it in the tank, it chooses the path of least resistance and comes out the coolant in the filler neck. It's worked for me for years...
Oh, did you put that little hole in the thermostat at the 12 O'clock position when you put it back in ? Did it even have a bleed hole ? I'd also put a new cap on there too..
 
I have no idea where I put the thermostat hole. the vacuum line is connected but the valve is weeping on the side a little. I'll try the squeeze method.
 
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