Bj70 heat

[alberta mac]

The heat in my bj 70 doesn't seem to ever get that hot unless the truck has been running for an hour.
Once the engine temps are up the heat seems marginal.
I'm wondering what I can do and look into ?

 

[JTarnow]

Diesels are pretty cold blooded but once the thermostat opens it should produce heat. There's a little flap in the heater box that is moved by the hot/cold control. I know the cable on mine likes to stick and sometimes pull out of the lever... maybe it could be something with that?

 

[jblueridge]

Having dealt with an MGB for years, I'd investigate the hot water valve on the head. I have no idea where it is but the control wire can corrode and the innards of the valve itself can crust up.

If you could remove the heater core (mini-radiator) you could see if it is partially clogged or the fins could be filthy.

 

[fossilcruiser]

My BJ70 barely produced any heat in front (rear heater was fine) last winter. I brought it to TorFab and they hooked it up to some machine to reverse the flow. It must have dislodged gunk because now I have plenty of heat.