A couple of weeks ago one of my 4.5v motors died so with a bit of help from a well known search engine's image facility I found these - https://www.langleymodels.co.uk/awd1/index.php?route=product/product&path=242&product_id=8439 and took the plunge and bought 5, including one for a LUG member. It fits and works perfectly. It was very loud at first but a drop of oil (from a model train store) did the trick. For around $20 including shipping to the US I have multiple new motors for a fraction of the price of 5 used ones on BL. 

(Mods, I've posted here cos I use mine only for trains, feel free to move to a different forum if there's a better place for this topics.)

I believe this is the perfect place to post your very nice find (and fix)!!! There is essentially no other forum that fits any better, I believe.

Would you know whether these motors also work within the enclosure of 4.5 "Technic" motors? These sell really cheap on EB, but I always lean towards fixing a suffering motor rather than dumping the entire assembly, just because it makes noises.

Thank you very much and all the best,
Thorsten 

I'm pretty sure they won't, I put the motor beside the technic one and there doesn't appear to be space for this motor to fit inside. The motor  body, before allowing for the protruding parts at either end is a fraction under 4 studs long.

I've used various non-LEGO motors a number of times in the past. They are dirt cheap, especially if you take them (and lights / LEDs, wires, etc) from old toys from a goodwill type store. Rather than trying to fit them into an old broken LEGO motor case, I tend to just build them into a small LEGO box made of plates and bricks or brackets. Then once assembled, glue a small gear onto the motor shaft. It is best to assemble the box on a larger plate to ensure it is the perfect size, then just dump a load of hot glue into it around the metal casing of the motor (away from the moving parts) to keep it centred in its new LEGO compatible case. They are ugly, but if buried in a model anyway it is not a problem. And as they are custom, you can have any LEGO attachments you like for the motor box - studs, technic holes, technic pins, etc and they can be different attachments on different sides.

2 hours ago, MAB said:

I've used various non-LEGO motors a number of times in the past. They are dirt cheap, especially if you take them (and lights / LEDs, wires, etc) from old toys from a goodwill type store. Rather than trying to fit them into an old broken LEGO motor case, I tend to just build them into a small LEGO box made of plates and bricks or brackets. Then once assembled, glue a small gear onto the motor shaft. It is best to assemble the box on a larger plate to ensure it is the perfect size, then just dump a load of hot glue into it around the metal casing of the motor (away from the moving parts) to keep it centred in its new LEGO compatible case. They are ugly, but if buried in a model anyway it is not a problem. And as they are custom, you can have any LEGO attachments you like for the motor box - studs, technic holes, technic pins, etc and they can be different attachments on different sides.

+1 for the Goodwill toys. Was very surprised back when I opened a PF m motor to find a bog standard motor one could find in a rc car.

ps. Would love to see some of your motors if you have photos!

I have the original motor from my Lego set 7720 (4.5v). It used to sreach a lot, but after I put a drop of oil on the motor shaft it was very quiet. The 44 year old motor is still going strong!