Thermostat With Or Without Hole/Valve

[Oka]

Two parts stores I checked don't have a thermostat with a hole/valve in it. What's up with that? I am used to using ones with a little hole/valve at the top plate. Can I use one without that?

Thanks

[Oka]

Two parts stores I checked don't have a thermostat with a hole/valve in it. What's up with that? I am used to using ones with a little hole/valve at the top plate. Can I use one without that?

Thanks

Just found this post: https://www.tccoa.com/threads/techni...d-holes.56182/

[Astro14]

Are you asking a general question? Or asking for a recommendation for your Volvo? In your car, get the one with the bleed hole, so that trapped air behind the thermostat can be better bled.

Best way to handle bleeding your cooling system is a vacuum lift, which is about $70 on Amazon. You’ll greatly reduce the amount of air in the system after cooling system work.

For brand, I would go with a Behr. Skip the local parts stores. I’m often disappointed by the quality and fit of parts for my Volvos when I’ve bought at a parts chain. Specialty Euro, or Volvo OEM, for me every time.
.
https://www.fcpeuro.com/Volvo-parts/...=5&b=6&d=55&v=

[br0dy]

Did not realize some MY of these vehicle you could just replace the stat. All mine were full-assembly PITA jobs. 1/4" flex-head ratchet, 6" extension, with 1/4" socket, with T45 taped inside of it made it slightly easier this one looks like a breeze to replace. I bought a "Gates" stat for one car, and a "FACET" stat for the other. Both are performing quite well.

[nickbw]

Defo "with": the thermostat should be replaced along with the new rubber seal so that the pin hole valve faces forward - this is the highest point in the cooling circuit. Doing so will ensure that the system burps any air and allows propper circulation of the coolant. NB Some people advocate parking the car heads up to a gradiant to enhance the burping. I find that all that is necessary is to fill the coolant header tank to Max and then take the car on a 1/2 hour run. The coolant will find its optimum level. PS When I replace the thermostat I also replace the coolant temp sender (22Nm torque) simples!