Hello, 1st post here. Have a 03 dually with the 6speed, 4x4 long box. Since I live in Canada, sometimes its cold outside. Bought a diesel engine heater, because sometimes where I go, no place to plug in. There is lots of places above the turbo in get coolant for the pressure side, but no place to return it. Don't want to return to the heater core, I want to heat the block only. Where the heater core returns at the front of the engine really dosen't allow for me to use it easily. Does any body know where there is 3/8 or 1/2 pipe on the return side of the cooling system. I see couple of plugs along the exhaust side of the block behind the turbo, are they pipe thread or cooling drains for the block? Went to the local Cummins dealer, partsman was confused, even when I pointed to the picture, service only hooks it into the heater core. Not what I want to do, thanks for any help.

 

Welcome to the site. When you say you bought a "Diesel engine heater", what exactly did you buy? Is it a Espar or a Blue heat. If it is one of these two makes you should ask the seller for the manual. I have only seen one Espar hooked up, lots of tight plumbing

 

Its a Webasto, I have put them on for years on truck diesel engines with lots of coolant ports. The manual with the book shows to put it where the heater core returns below the alt, but only one port there, with the steel pipe not alot of room, since I am **** about things, there is always a better way. I figure out the size of the plug in the block 18mm by 1.50mm pitch and its orb style, got a fitting, but it cost $15 for 1 fitting, great deal.

 

I'd go ahead and install it in the heater line. As long as there is no air blowing through the heater core, it's not going to dissipate too much heat.

There will be some convection heating of the ambient air, drawing a VERY slow velocity of air through the heater core, but that will be so minimal that you wouldn't notice it in the heating of the engine.

HTH

Tony