Have had to remove a few speed sensors recently to replace failed ones and every one has had seized retaining bolts which is not unusual given that most of them have never been replaced before and succumbed to rust in the sensor mounting hole and the retaining screw bolt and threaded hole. The allen headed bolt on all of them rounded out and even trying to break them loose with molegrips didn't work. The method I found to work was to grind the top of the bolt off flush with the sensor face then carefully pry the sensor body out and off what was left of the threaded shank of the bolt.
To extract the remaining bolt shank from its hole I used heat from my Mapgas blowtorch which produces a very high heat. Heated around the base of the bolt shank at the hub for around 30 seconds and then clamped molegrips to the shank and got it to move, went back and forwards with it to ensure it freed up then unscrewed it from the hole. The sensor mounting hole was cleaned out using a wire brush in a power drill and the new screw had a dab of coppereaze grease applied to it when reinstalled.
To extract the remaining bolt shank from its hole I used heat from my Mapgas blowtorch which produces a very high heat. Heated around the base of the bolt shank at the hub for around 30 seconds and then clamped molegrips to the shank and got it to move, went back and forwards with it to ensure it freed up then unscrewed it from the hole. The sensor mounting hole was cleaned out using a wire brush in a power drill and the new screw had a dab of coppereaze grease applied to it when reinstalled.
Last edited: