2016 High quality 2-PCS Anti-static Tweezer Sets for Netherlands Factories

via YouTube Capture

Please read the description below for a few extra tips.

This short video presents step by step a way to replace the thermostat in Volvo models from around 2003 to 2007 (S60 and V70 with the 2.4 non turbo engine).
The replacement part used in this video is a Beck/Arnley #143-0850 about $100 off Ebay.
On a russian forum, a member has reported having successfully installed a Gates TH35991 thermostat in a 2008 2.5T Volvo XC90, after swapping the gasket from the original thermostat. This might work on a 2.4 engine but hasn’t been tested yet.
See this link https://clubvolvo.ru/showthread.php?t=…
The idea is to get easy access to the thermostat housing. Instead of replacing the whole casing, I only removed the upper half casing, the removed the old thermostat from inside, and replaced it with the new thermostat. I did use the new upper half housing with the new thermostat, as well as the new gasket between the two housing parts.
I did not replace the whole housing, because the rear bolts to the engine block were hard to access. Instead, I removed the two torx screws that keep the two half parts of the thermostat housing together. Note that those screws have Loctite on them and may be very hard to remove. They were hard to remove even from the new thermostat housing. If they don’t move, or if you happen to strip the head, try moving them with a vise-grip (locking pliers). Some people had luck using an universal joint 1/4″ socket adapter to reach the torx bolts without removing the power steering pump.
The coolant bleeder under the radiator is a sensitive plastic piece, don’t force on it, or it may break. Only tighten it gently back by hand using a torx socket with extension until it feels just a bit tight, say much like your home faucet handle. If you can’t release the bleeder just disconnect the upper radiator hose and drain all the coolant from the thermostat (you may cover the alternator with a plastic so it doesn’t get wet).
When refilling the coolant, let the engine run until it gets hot to bleed all the air in the system while constantly monitoring and topping up the coolant reservoir. The level needs to be topped again the next morning when the engine is completely cold.

Checking for a stuck open thermostat
Usually the thermostat will fail open position because the sliding pin inside the t-stat corrodes and gets stuck. The symptoms for a stuck t-stat is the engine will take longer to get the temp needle at 12h in cold weather, and the cabin heater won’t blow hot air except after hard acceleration. To check for a stuck open t-stat start the engine from cold, let it idle 2 minutes then touch in the middle the upper thick radiator hose that goes between the stat housing and the radiator. If it’s warm it means the stat is stuck open and needs replaced.

Volvo forums

https://matthewsvolvosite.com/

https://volvoforums.org.uk/