thermostat housing replacement

2005 TOYOTA SIENNA
127,000 MILES • 3.3L • V6 • 4WD • AUTOMATIC
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IMAGING
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  • 151 POSTS
When uninstalling the thermostat housing, will the thermostat fall out?
If it does fall out, how do i know the position or angle it should go back correctly. Do I need to replace the gasket on the thermostat? It's a brand-new thermostat and gasket just installed about 6-7 months ago along with the radiator and lower and upper hoses.
Nov 9, 2021 at 7:04 PM
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JACOBANDNICKOLAS
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Hi,

Since the thermostat is still basically new, you can reuse it. However, I would recommend replacing the gasket.

As far as the thermostat, it will likely be stuck to the engine, so it shouldn't fall, but it is possible.

When reinstalling, simply place the giggle valve at the specified location in the directions I sent on the original post. If you are concerned that it may fall or move, put a couple of small dabs of gasket maker on the thermostat outer ring, position it where you want it, and it will stick. Wait about 20 minutes for it to set before continuing.

Let me know if this helps.

Joe
Nov 9, 2021 at 8:48 PM
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SQM
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Hello,

When the thermostat hosing gets removed, the thermostat should not fall out as it fits snugly inside the housing.

I have included the replacement procedure for the thermostat, which shows the angle it needs to be installed, just in case it falls out.

Please let me know of any questions.
Thank you.

https://www.2carpros.com/articles/how-an-engine-thermostat-works
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Nov 9, 2021 at 8:49 PM
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IMAGING
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Now, there's no way to remove and install the thermostat housing without removing or just loosening up the starter.
Nov 10, 2021 at 2:23 AM
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SQM
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That is correct, you will have to remove the starter along with the air filter box and battery.
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Nov 10, 2021 at 7:27 AM