BMW M50 Power Steering Delete Belt

My e30s both have their power steering deleted, but the M50 from the later e36 uses a serpentine belt that drives the water pump, alternator, and p/s pump all at the same time making impossible to “just remove the belt” to prevent the p/s pump from running like on the old M20 or the early M42. However, there is a solution – by completely unbolting and removing the p/s pump from the M50 a different, shorter serpentine belt can used with an alternate routing to effectively delete the power steering. You should not run the p/s pump without fluid. Different part numbers are thrown around, generally ranging from a 6PK1400 to a 6PK1415, with 6PK1410 in the middle. Let me decode those numbers – the first “6” means the belt is a 6 rib serpentine belt and basically determines the width. This stays constant. The last four numbers are the belt length in millimeters, making a 6PK1400 belt 1400mm long. That’s simple enough.

I kept my idler pulley (the one above the alternator) and successfully fitted a 6PK1420 Serpentine Belt from Advance Auto (Part # 560K6). This belt, as mentioned above, makes it 1420mm in length. It was a snug fit, but not quite as tight as the factory belt, so I’m sure a 6PK1415 could also be used. Some people elect to delete the idler too and use a shorter belt; I would recommend keeping the idler as it gives the belt more grip on the alternator & water pump.

  • Hi I have just read your brief article on replacing a belt to an engine with no power steering unit fitted. I am building a kit car in the UK and the donor engine is a BMW 3 series E36 but with no power steering pump. You appear to have solved this but can we chat in more detail. I would like to send a couple of images and seek your input. Look forward to hearing from you. Regards Ian Milliken