I have after market heater on my 54 3100. The fan works but I get no heat. The heater hoses are hooked up to the firewall with nothing
in-between it and the engine. Should I take off the heater hoses and see if there is valve or something? It does not leak. What can I do? The heater was on it when I bought it and I don't what brand it is or how it works. I can't drive it in the winter because of no defroster working.
First, disconnect both hoses from the engine and try to blow through either one of them. If you can't blow through, find out where the blockage is. If you can blow through, what engine do you have and where on the engine are the hoses connected?
Ray
Those who choose an automatic transmission want transportation. Those who choose a manual transmission want to drive.
Air trapped in the system, heater hoses connected incorrectly. If the heater hose connections on the core are vertical then the hot water hose should go to the bottom connection. Make sure the hot water hose is hooked to the proper location on the block.
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Both heater hoses get hot but only a little warm air comes out the vents. The temp gauge reads just before the middle. Could I have the wrong temp thermostat?
I'm no expert but it could be a flow problem. I would use the blow method. Switch could be clogged up or partially closed. Maybe there is so much gunk inside that you are not getting heat transfer. Also might want to check inside the box and see if a mouse or wasp has made a cozy home around the coil. I would start with a good cleaning of all parts inside and out.
If both hoses get hot, this means you are getting flow through the core and your thermostat is ok. Your next move would be to open up the housing as suggested and look for an air flow obstruction.
Ray
Those who choose an automatic transmission want transportation. Those who choose a manual transmission want to drive.
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