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Block Heater

TheRiGuy

New member
Does anyone know the part # for the OEM block heater and/or cord for at 2007 GP with a NA 3800? With temperatures getting down to near -40 here in the great white north I figured it would be a good idea to check the resistance at the plug of the block heater to make sure its working and unfortunately for me its open circuit. Its my understanding that the cord end has a built-in temperature switch that opens at warmer temps which could be stuck open so if i chop that off and just put on a normal 120V male cord end that might fix it temporarily but if not how much work is it to replace the entire block heater and/or cord?
 


I always popped the cap off the thermostat on the cords, then broke the thermostat out of there.

Then took a piece of wire to connect the two metal tabs together again and used solder to complete it. Push the cap back into place and it worked like a charm at any temp.


My cords on the last few GM vehicles used this style plug end.

112695687766_1.jpg.jpg
 
I always popped the cap off the thermostat on the cords, then broke the thermostat out of there.

Then took a piece of wire to connect the two metal tabs together again and used solder to complete it. Push the cap back into place and it worked like a charm at any temp.


My cords on the last few GM vehicles used this style plug end.
I didn't realize there was any way to get to the thermostat without cutting the rubber. If that piece just pops off i should in theory be able to test the t-stat and heater itself directly from there. I'll probably need to blast it with a heat gun to soften it up first though lol. Thanks for the quick replies!
 
Get a little mean with it and it'll come off.

I take a good pair of vise grips or nice pliers, grab the cap and twist/pull it out.

The plastic cap sits in a special ring cut in the "housing" if you catch what I'm saying. The cap has a lip and that sits into a cut in the plug end. It just take a little muscle to get it out and back in.
 
I installed a block heater on my 04 without too much pain and suffering... I had pulled off the front air dam already so I could reach the side of the engine block from underneath. It took me about half an hour to knock the freeze plug out and get the block heater pounded in.
 


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