1992 745 w/125k miles. My replacement radiator has a plug in the switch hole. It came out easily and the bushing stayed in the radiator. My old switch looks like it may have been glued in. I cleaned it and it pushes in my new radiator quite easily. It doesn't seem right; like it would blow out with little pressure. How does that thing work? Thanks, C

 

Isn't there a threaded ring that holds the thing in?

 

No, this is push-in only. There isn't much of a waist on the sensor and my factory one had rubber stuck to it like an adhesive or sealant had been used. I'm buying a new switch and grommet. Thanks, C.

 

Should not be a problem. The rubber bushing just pushes in and the switch just pushes in the bushing. It doesn't need any sealer and should not leak. I assume you use a new bushing when you install a new switch.

 

"Fascinating." -Mr Spock.

 

Just to shed some mud on a murky subject. There are three variety of radiators as regarding sensors. 1. No sensor hole 2. Push in friction fit (what you have) 3. Screw in sender switch. They aren't interchangeable. The screw in sender is different. When replacing a press in sender style radiator, it is HIGHLY recommended that you buy the female bushing that fits into the radiator. Volvo sells them for a few bucks. FCPGroton sells them too if time isn't an issue but shipping makes Volvo cheaper. The sender should be tight as you press it in. The bushing that was in your rad was for the plug, which is often a greater diameter than the sender. Get a new bushing or you will have major issues. No sealant is used. On the bright side, if the sender blows out and you warp the head, I have a nice used cylinder head for cheap!!