It should have a thermostatic bypass around the radiator that keeps the temp up. I would not remove the engine thermostat. Make sure it has the radiator bypass installed and working properly.

 

Hmmm ok. I’ll take a look in the morning. Maybe I’ll post a few pics of the install and post on here. The previous owner said the heater worked that way since it was installed. Perhaps somethings not installed right...

 

Look for this:

 

Ok. So that’s the thermostatic bypass? How is it supposed to be plumbed?

 

Thermostat is on the entering side of the radiator (driver side). Can't remember thermostat temp setting (I think it's 160) but it closes and flow through the heater core and around the radiator. Should be a "T" on the exiting side of the radiator where the return from the heater core is plumbed.

 

Thanks very much for the info buddy. I’ll take a look and see if everything is correct. Appreciate your help!

 

I have the same problem but I found an easy cheap fix. put a piece of cardboard in front of your radiator that covers about half or maybe a little more of the radiator. I open the grill and put it against the radiator. It will keep your temp about 185 to 200. I had to experiment on how much to cover so I have a piece of cardboard with a fold to open it up to cover more of the radiator if needed, up to 3/4 of it covered. it works well

 

Thanks guys, all the plumbing etc seems to be installed correctly. Went for the cardboard fix and worked like a charm. Covered 3/4 of the rad and and running about 190 and getting decent heat. Thanks for all the replies guys.

 

You shouldn't have to put cardboard in front of the radiator, though I have a Motoalliance heater in mine, it gets up to temperature even at -10 degs F. What I'm thinking is that you could possibly have air at a high point in the system, if there's a hose clamp somewhere close to a high point, you might loosen it up to bleed any air off until you get coolant out of it.