Replacing A VW Starter motor bush

24th March 2012
I knew my starter motor had failed with a broken winding and thought that it was likely that this was due to a worn starter motor bush that had caused the windings to hit one of the magnets.

There are two types of starter motor bush one which is a 12v bush and another which is a 6v bush that converts to a 12v starter motor. It is important to get the correct one.

The starter motor is fastened by only two bolts top and bottom the top goes right through the engine casing whist the bottom is a short stud. It is very important not to loose the top bolt as it has an unusual D shape end. Once removed the hole in the gearbox can be seen and the bush contained in the centre. A 12mm tapered tap can be wound into the bearing by hand so that it starts to bite I used a pair of grips on the end of the tap so that it could be turned in the small space as the tap handle did not have enough room to turn. You need to keep turning the tap until it bottoms out on the hole. This need quite a few turns to complete but eventually the bearing moved up on the tap and out of it hole.

You can see from the picture right that the bearing has been wound onto the tap with the depth of the tap protruding from the end of the bearing being the depth of the hole from which it came from. I tried the new bearing on the end of the tap and noticed that it slipped easily on and off without interference. I decided that I could use the tap to replace the new bearing . I greased up the new bearing and slid it onto the tap. I removed the adjustable and sat the whole assembly in the hole. I used a rubber mallet to softly tap the end of the tap and the new bearing into place. The tap was then slid back out to leave the bearing in place see picture right. This whole procedure took a very short time and to be honest I would recommend replacing this bearing if you are replacing a starter motor. The replacement starter motor was refitted . It can take a little time to mesh the gears when refitting this may involve using someone to turn the engine or you will have to move the starter gear and replace the motor until it goes completely in. The two bolts were replaced and torqued up. The wiring on the back of the solenoid was reconnected and the job was complete.