crank sprocket, remove and replace question

[typhoon320i]

Since my car likely has the original timing chain and sprockets, I'm going to replace all.

Question: is it going to be very had to get my new double layer sprocket, onto the crank?

I thought I saw somewhere that said it is an interference fit. So I guess I would cook the sprocket in the oven to like 500 degrees and then try and get it on. (block still in vehicle)
Does anyone have any input? Is this going to be a real pain to do?

[autox320]

Since my car likely has the original timing chain and sprockets, I'm going to replace all.

Question: is it going to be very had to get my new double layer sprocket, onto the crank?

I thought I saw somewhere that said it is an interference fit. So I guess I would cook the sprocket in the oven to like 500 degrees and then try and get it on. (block still in vehicle)
Does anyone have any input? Is this going to be a real pain to do?

Yes use an oven 450F for several minutes. Carry with welding gloves to the crank. Make sure the key is on the crank and already in place. Slide on to seat it.
This procedure is even in the M3 S14 manual how to get the gear on.


If removing one just use a puller and heat with a handheld propane torch evenly. When hot enough usually over 200F it will start to pull off easily.

General rule of thumb is grows .001"/100F/1" diameter. So gear internal dia is about 1", it will be about .004" clearance when heated to 400F, plenty to slide right on there.

[typhoon320i]

Alrighty then. I have my mission.

[typhoon320i]

Should I put any oil on the shaft to lubricate when seating the hot sprocket?
Or is that not a good idea?

[autox320]

Should I put any oil on the shaft to lubricate when seating the hot sprocket?
Or is that not a good idea?

No. Clean, dry, make sure the key is there. Heat and slip on with gloves. Push back till it stops and hold it there a few sec, then let go and cool.