Wiper Motor Removal

[LionelT]

I need to remove my S1 3.8L windscreen wiper motor for rebuild, but the crank inside the scuttle will not fit through the hole in the firewall. I cannot turn the motor more than 5-10 degrees because it hits the sides of the well it is installed in. It seems like it might come out if the crank was in a different position, but the motor won't run and the worm gear is not reversible.

Am I doing something wrong? Any ideas?

[cactusman]

You can refurbish the motor by removing it from the crank mechanism in the engine bay. Firstly disconnect the six wires at the block on the bulkhead. Look at the motor/crank unit and you will see an access plate held on by a few small bolts. Remove this. You may need to remove the throttle linkage to facilitate access. Inside you will see the worm drive with a large toothed wheel that drives the crank mechanism and a worm screw which is actually the end of the motor shaft. Now feel the other end of the actual motor. You will find two bolt heads. Undo. A bit fiddly but perfectly possible. This will release the motor housing and armature such that the armature, the housing with the field coils and the end plate can be removed. You can then replace the brushes, clean the innards, 're oil the phosphor bronze bearing and felt pad in the end plate and possibly replace the wires if they are crumbling. Refitting is the reverse but take the opportunity to scoop out any dry and waxy grease from the worm and wheel box and 're grease. I have done it. Fiddly but perfectly straightforward. If you need new wires there is a bloke on eBay in the US that periodically sells sets with the correct cloth covered wires in the correct colours. Not cheap but a nice finishing touch.

[geoffh]

A variation of cactusman's method also works to remove the motor from the car if the crank is initially in the wrong position. After disconnecting the wiring and the snap connector, there's no need to remove the bright plate from the top (crank end) of the motor, but you remove the die-cast aluminium bottom plate assembly after undoing the two long bolts as cactusman describes. Then you can hold the armature at the commutator, and rotate it (mind the brushes). A few turns will rotate the crank end until the crank pin points to the right-hand side of the car. Then the motor can be moved towards the centre-line allowing the crank end to pass forwards through the hole in the firewall. Finally the motor goes downwards, forwards and rightwards until it's clear. Some care needed so that the plastic insulator doesn't fall out from the brush assembly. The engine is out of my car so I could stand in the engine bay, which made the job easier.
Geoff