2nd Gen Non-Engine/Transmission No heater

[DDemere]

I have no heat in my '96 2500 4x4. It froze here in central Texas the other day, and I could not keep my windshield defrosted going down I-35. Pretty hairy drive, so now I need to fix my problem before next freeze. The blower works great, but I never really get hot air with the temp. control turned all the way to the red. Thanks in advance.

 

[Beach]

Are the two coolant lines going into your fire wall to the heater core both hot? If not, you might have an issue with a blockage! I've been batteling low heat, and this was one thing I checked. I dont know if the 12 valve motor's are the same heat set up as the 24, but you can disconect those two hoses and flush them with a garden hose carefully to try and dislodge anything that might been blocking it. I used a barbed hose connector and hose clamped it to the inlet hose, and then the outlet hose, flushing in both direction's. I wouldn't run the hose all the way open. Just enough to get a good flow to see if it's blocked. You might want to check the Thermostat also! I don't know if any of this help's, just thought I'd give some suggestion's! Good Luck!!

 

[jhoughton]

Mine did a similar thing when it was only a couple years old. The engine temp would not come up very much from cold. Ended up being a broken thermostat. Once replaced engine warmed up and heater worked normally. Bought the thermostat from the Cummins dealer since Dodge was way to expensive. It was not available from a parts store at that time. You should be able to get yours from any parts house. Good luck I know it can be a PIA especially when you need it.

 

[DDemere]

Thanks guys, I'll try a new thermostat first. If that isn't it I'll try flushing. It's probably a good time to flush out my coolant system anyhow.

 

[Dennis Garrett]

Don't use too much pressure flushing the heater core, you can split it if it's weak. The can be pretty delicate if they have a few years on them. One time my daughters old Chevy wasn't getting much heat because of an old corroded core. We took the hoses off, and ran some "Lime-Away", or "CLR" or whatever through it, and let it stand for a few minutes, and that helped cut out some of the buildup. Worked a little better after that. I've wondered about using nothing but distilled water from the start on a new motor to keep that buildup to a minimum.