Thermostat Gasket

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Wahooo
Posts: 39
Joined: Sat Oct 02, 2021 12:49 pm

Thermostat Gasket

Postby Wahooo » Thu May 26, 2022 4:07 pm

Doing some cooling system maintenance this weekend, woo fun!
Thermostat gasket comes with sealant pre applied on the thermostat side but not the engine side. I can't imagine they don't want something on the block side.
I plan on using the same sealant I'm going to use on the cam chain tensioner cover and water pump cover.
Sound about right?


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VStar650CL
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Re: Thermostat Gasket

Postby VStar650CL » Thu May 26, 2022 5:43 pm

The 'stat side can be replaced easily if you gouge it with a scraper, the block side not so much. If you really want to seal both sides, use something that comes off easily with solvent and not explosives. :wink:

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smj999smj
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Re: Thermostat Gasket

Postby smj999smj » Fri May 27, 2022 7:43 pm

Permatex Copper Spray Gasket is a good option.

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Wahooo
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Re: Thermostat Gasket

Postby Wahooo » Wed Jun 22, 2022 11:30 am

Cooling system upgrades completed and tested all good.

Got the truck in Sep w/90K and immediately changed out the radiator with a Koyorad from RA at a smoking price. Everything else looked good enough from the outside to put off anything else cooling related until spring.
So beginning of May a couple of 80F+ degree days and I notice the temp gauge moving up to just over midpoint, not overheating but not what it was all winter and early spring. OBD2 reader live data showed temps moving up to to 220's.
LET THE FUN BEGIN!
I had the cooling system parts purchased in the fall,
OEM Thermostat
Aisin water pump
OEM fan clutch
Timing chain tensioner

Overall not the hardest job to do but some things I did notice:
I could not get the timing chain tensioner to retract so I could pin it in position. Removal destroys the super thin gasket behind it. Glad I bought a replacement one just in case of this. (thanks RTCG!)
Found out you should grease/oil the water pump O-rings, after I installed it. It went in so smoothly though. no harm no foul.

NOTE: 12 year old, 95K mile OEM water pump looked brand new. This was an unnecessary replacement. Do these things even go bad?

Thermostat replaced with an OEM one and a FelPro paper gasket with some type of orange sealant pre-applied to one side.
Here was my problem, what I removed was a cheap POS $9 motorad thermostat. JUNK. And whatever sealant they used took over an hour to remove.
The OEM thermostat was $25.
FelPro gasket was garbage, used Permatex water pump/thermostat sealant. Leaked like a sieve.
NAPA had a metal (tin?) gasket and Permatex Copper Spray Gasket was the perfect sealant for that.
https://www.napaonline.com/en/p/ATMTG07 ... sionRank=7

Slap on a new OEM fan clutch, probably a waste of money there too, and done.
A/C condenser electric fan tested good so it got to stay.

Stop and go traffic, Chicago 95-99F days, A/C on and this thing sits about 193F solid.
I'm going to put this one in the win column.


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