I was getting a slight leak from the bottom of the thermostat housing on my '04 Hemi QC 1500.

I pulled it apart tonight and there was no paper gasket in there. Autozone had a paper one specified for it for $5:
http://www.autozone.com/autozone/par...5817_188054_0_

So, I bought that and put it in there. Will drive in the AM to see if it fixed the leak but should there have been a gasket there? There was the rubber gasket around the thermostat itself but I'm not sure if that is designed to seal the housing to the pump/block too. I'm the 3rd owner so it's possible someone has been in there before.

BTW I wouldn't describe the bolts as loose but it didn't take too much effort to break them loose with a 3/8" drive ratchet.

Thanks,
Jeff

 

looking at the hemi section of my shop manual, no paper gasket is mentioned. only the grooved rubber o-ring on the thermostat itself. the torque specs show something like 112in/lbs of torque, very easy to take out, just enough torque to put a good squeeze on that rubber ring and create a good seal.

however, they can be kinked/pinched quite easily during install.

 

Ok, thanks. I don't see how the paper gasket could hurt I guess. We will see if it leaks tomorrow. I ran it tonight with no obvious leaks but everything was wet from pulling things apart.

 

Pretty much all of the gaskets on the engine (minus head and exh) gaskets are a rubber bead type gasket that fit down in a channel.

The actual part number is 53020887AB and cost about $10-15 depending on where you get it

 

There is not supposed to be a paper gasket on the Hemi thermostats, just the rubber gasket and the torque on the bolts is only supposed to be about 10 ft-lbs. After changing my radiator hoses I decide to change the thermostat on my 03 Hemi. I bought a new one from the dealer and installed it. It worked fine until the weather turned cold and it started leaking only when cold sitting in the garage. I thought the rubber gasket was bad. I tried to buy the gasket separately, but they don't sell them. So I bought a whole new thermostat again and installed it. Again, it worked for a while until the weather turned cold again and it too started leaking when the engine cooled down. This time I went to NAPA and bought one from them. I noticed several differences. The rubber gasket was black instead of red, the rubber was more pliable and softer, and the rubber was thicker offering a better seal. I installed it and torqued it 10 10 ft-lbs and so far it's working great.

 

Same problem here with the weather. I bought the truck in the summer and no leak. Once it got cold it started to drip all night and make an orange stain on the driveway. I hadn't noticed a leak while it's running but assumed it was just because it was a slow enough drip that it evaporated off. Mine does have the red rubber gasket like ejw describes.

So far the paper gasket on the flange has been OK but it hasn't been cold yet. If it doesn't take care of it then I will grab a new thermostat at NAPA with the black gasket.

BTW I couldn't find the HOAT coolant anywhere (Walmart, AutoZone, Pep-Boys). I was looking for the Zerex G-05 but all anybody had was regular green Prestone and Dexcool. I got tired of looking so I grabbed a gallon at the Dodge dealer. Almost $24 with tax! I will definitely try to find the Zerex stuff when I do a complete drain and refill.

 

Well, no love from the paper gasket. It still leaks. I will stop at Napa and grab a thermostat with the black gasket on the way home.

 

Jeff d, let us know how it works.

 

you sure its coming from the thermostat and not the water pumps weep hole? Mine was wet around the housing and ended up being the weep hole and needing a new water pump

 

I'm not 100% sure since it's hard to see down there. From what I've been able to tell it is coming from the thermostat.

It's possible that it's running down from somewhere else and dripping off the bottom of the thermostat housing though.