Starter Binding

[mark///m3]

So I've got a weird new problem.....

The starter solenoid is engaging but the motor won't spin over. I figured bad starter so I ordered one up. I pulled the old starter out and bench tested, it worked fine. I figured I would try the new starter out anyway, same result. I wanted to rule out a bad ground or a power issue so I went right to the starter with battery power and ground, same thing the solenoid engages but the motor cannot turn.

It seems the starter and flywheel are binding. It is a factory bosch starter and a uuc light weight flywheel.

I was fed up for tonight but I will be pulling the starter tomorrow night again and checking out the starter gear to see if anything looks off.

[JGood]

So you hear the starter click, but that's it? The starter doesn't 'freewheel', and the engine doesn't spin either? Can you turn the engine over by hand?

What model UUC flywheel are you using, and what part number is the starter?

[mark///m3]

The car turns over by hand, and runs fine when pop started. I can hear/ feel the starter gear jump forward just no motor engagment.

The flywheel is for an e39 540i and the starter is for a 95 540i.
12 41 1 736 921, Bmw. SR 0446 X, Bosch.

[JGood]

And when you bench tested it, the gear popped forward AND spun? When the starter is installed in the car, you hear the gear pop forward, do you hear it grind for a split second or anything? I know you said you hooked up a seperate power and ground, but is your main engine ground in place with good connections?

That's the same flywheel and starter that I'm using.

[mark///m3]

So turns out I'm the lucky guy who got a bad rebuilt starter. I put another rebuilt bosch in and this one works great. I should have known, i've had some weird problems with this car over the years.