Dowel Pin Missing From Vibration Damper!
 

This is my first attempt at a timing belt replacement on my 1985 325e. Everything went relatively smooth until I removed the six bolts from the crankshaft pulley. The pulley came right off, and I noticed that the vibration damper was able to rotate freely, even though it is supposed to be keyed in place by a small steel dowel. I took the damper off and saw that the pin was either sheared off or pushed in.
I had the timing belt replaced about 10-12 years ago at a local garage, so if any damage was done to this pin it must have happened back then.
So, I'm wondering if anyone here has ever run into this before?

In order to align the timing marks, I'm going to place the damper in the position it "would have" been in if the pin was there. There is a small hole between two of the bolt holes where the pin is supposed to go into. I'm then going to put two of the bolts back in, hand tight, and line up my TDC marks. I "think" this should be sufficient. Any thoughts or advice on this?

Go to your BMW dealer (or local hardware store ) and get a new key. (Its called a "woodruff key" at the hardware store.)

It can't cost more than a dollar or two.

It doesn't have woodruff key. It's actually a round pin or dowel about half the diameter of the mounting bolts and located between two of the bolt holes on the crankshaft sprocket.

Had a tough time putting new timing belt on
 

I read many instructions on doing the timing belt on my 325e, but none of them made any mention of difficulty putting on the new belt. I had the tensioner pulley pushed all the way back toward the passenger side and tightened down, started from the crankshaft and worked my way up counterclockwise, but the belt was SO TIGHT that it was a huge pain trying to get it on! I had it on all the sprockests and saved the tensioner for last. All the instructions I read said NO NOT use any tools to get the belt on, so needless to say it was very frustrating. I ended up using the wooden handle of a rubber mallet for leverage and wedged it between the water pump and the underside of the belt. I was able to force it onto the tensioner pulley but had to remove it twice because the camshaft sprocket moved slightly and had to be realigned. I finally got it on without changing the alignment.
My next screw-up was forgetting to put the engine hoist bracket back on when I tightened the bolt on the upper cover. I ended up stripping the threads in the hole. So now I'm hoping that if I find a slightly longer bolt of the same thread size I will be able to catch some threads and tighten it down.

On the subject of pins and keys. According to the TIS your car ('95 e36 325 w/M50 engine) should have both a "featherkey" and a dowel pin. The featherkey is used to anti-rotate the flanged hub that the vibration damper/alternator/water pump belt pulley mounts to. The key fits in a slot milled in both the crank shaft and the hub and anti-rotates them together. If your car does not have the featherkey I would be very surprised. Even Chevys have them. The pin on the other hand should be located in the fange on the hub and is used to orient the vibration damper position, with your timing marks, to the crank position. If either of those two parts, key or pin, are missing you run the risk of the harmonic damper slipping relative to the crank position. I just can't see anything good about that happening.

On the subject of the stripped thread, my recommendation would be to get the correct tap for that sized thread and chase those threads to clean them up before trying the longer, not larger, bolt.

I have no experience with the belt on your car. According to the TIS it appears that you have the dual roller/pitman arm pulley configuration. My suggestion would be to make sure that everything is installed/assembled correctly and make sure you have the belt routed correctly around the pulleys, the alternator and the water pump. You might also check to see that you have the right belt. The single pulley set up in the later M52 engines may be a bit different in length, i.e. shorter. Also make sure that the piston damper on the hydraulic belt tensioner is working properly.

Just to clarify, I have a 1985 325e, m20 motor. The dowel pin is what is missing/broken and as long as I orient the vibration damper in the correct position, the six bolts hold it in place. I believe the pin just prevents the damper from being installed with the wrong orientation in reference the the TDC mark. I believe I have it lined up correctly, and my TDC marks ar lining up at the camshaft & crankshaft markers, with cylinder # 1 at TDC.
As far as the belt goes, it is just the timing belt I was referring to. I believe it is the correct belt but it is surprisingly tight. This IS my first attempt at a timing belt installation, so I guess it's possible that I just don't have the technique down. I
struggled with it for about two hours.

Now the strpped bolt hole....I stripped it so bad that the bolt just slides all the way in without any resistance. I think if I try to re-thread the hole, or clean it up, I will have to go with a larger size thread. I think I will try a slightly longer bolt first. It seems to be the easiest way out if it works.