Tapping into cooling system

[Xmas1]

I installed a coolant heater over the weekend and I don't think I have the flow correct. I tapped into the line that goes from the block to the heater core. I used the one closest to the driver's side and I'm feeding into the heater core first. The problem is that the pump is working but I don't think it's moving the water. Is there a better place to splice into the system and should I be heating the block before the heater core?

[DmaxMaverick]

Using the heater core circuit, you are essentially only heating the heater core. The routing of the heater core is: water pump, heater core, lower radiator hose, water pump. Any heated coolant (using your heater) that gets outside that loop would be incidental. A closed thermostat would reduce the flow outside the loop even further.

[Xmas1]

I installed the unit inline. My thinking was that the water would be pulled from the engine and pushed through the heater core back into the block. As you mentioned the thermostat may be the problem. How do most people hook into the engine for this type of hookup?

[DmaxMaverick]

That would be a good question for Greg Landuyt ( www.lubricationspecialist.com (http://www.lubricationspecialist.com) ). He's sold those things for years. If he doesn't jump in here, shoot him an email.

As for me, I live in California. Not really much need for one. It would be a nice-to-have in the winter for instant heat, but by no means necessary.

[rob@rone.ca]

Mine (05 sold in Canda) came with one. It's not listed as an option, so I guess its standard equipment here.

It's a bear to find it, the cord is hidden (coiled up) down low alongside the engine on the passenger side.

It goes to a plug-type element in the lower part of the block.

The separate DMAX manual has info on it under the title of "engine coolant heater"

[DmaxMaverick]

Rob

Different heater. The A/C block heater is standard equipment on GM Diesels, since forever.

He is refering to a pump/heater plumbed into the coolant circuit. Either elecric, or fuel fired.

[LanduytG]

If you are using and Espar you have it right. You go in series with the heater core. Drivers side hose is the inlet to the core. The pump should have its discharge to the core. Also the pump needs to be in the right position or it will not pump well at all. You will know if its pumping OK by running the heater. If the heater shuts down soon after it starts its not pumping. It will heat all the water in the block very quick. I need to get some pics posted of my install. Very slick and looks OE and unless you are looking for it you would never know its there.

Greg

[Xmas1]

It's an Espar that was actually purchased from Lubespecialist. We got two one on my '03 and one on my friends '05. I have mine installed on the passanger side, outside frame, with the pump right next to the unit. The discharge of the pump is going into the unit and the units discharge is going to the heater core as described earlier. When I start the unit the pump turns on and the unit also turns on, but the lines coming out of the heater core don't get hot, neither does the block. The hoses between the pump and unit get real hot then the unit shuts off.

[LanduytG]

You need to make sure your heater control on the dash is all the way to the hot side.

Greg

[Xmas1]

All is working good now. There must have been air in the lines, once the over fill tank settled back down to it's normal height the unit is good to go. I tested it again today after everything cooled back down and it's working as advertised. The heating unit heated the coolant in less then 15 minutes.