So when I removed my oil pan from my R53, I found some lovely pieces that would go nicely in the trash because they shouldn't have been there. So while I'm replacing my chain guides I'm also replacing the cam and crank sprockets and the chain as well. I have yet to find good info on how to remove the crank sprocket. Can someone point me in the right direction?

 

I read in the Haynes Guide (for that that is worth) that you need to heat it so it will slide off. Something like 300 degrees or some such... The book is only about $15 and reasonable guide on how to take things apart and get them back together though Haynes does assume you have all the right tools and know a little more then that basics on rebuilding an entire car.

 

FYI
I m resurrecting an old thread, but today I was searching for the same info and I did used a torch to heat the sprocket along with a three legs extractor(puller). I did followed an advise to screw the original bolt almost all the way in to use it as leverage I supposed and some elbow grease applying heat dw40 on and off.
i would post pictures for the diy’s.
my cooper is a r52 2006 base convertible, I’m doing a lot to my Mini I bought in Nov and i’ve being busy.

 

The crank sprocket on my R53 was a bear to remove. I first tried a rental 3 jaw puller from Autozone and heating the sprocket, but the puller jaws would just pop off. So, I ordered a 2-1/8 bearing splitter from Amazon. It was a tight fit, so I had to use slight smaller bolts to angle it into position. Here it is with an rental Autozone timing gear puller and a scrap of chain wrapped around the sprocket to try to get a better purchase on the gear:

I cranked and cranked on the puller, also heating the gear with my propane torch until the teeth began to snap off the gear and the puller bolts bent. The pulley didn't budge:



So I used my Dremel with a tungsten carbide bit to grind through the timing gear at the keyway and it popped right off! It took less than 10 minutes and since just ground to the keyway, I didn't nick the crank at all:


I put some strong rare earth magnets near while I was grinding to catch the filings. The magnets caught a lot, but they still went everywhere and stuck to the oily face of the block. I hosed the face of the block off with brake cleaner, so I could clean the filings out of the oil pan with the other oil pump and timing chain guide debris. One bad surprise is that the filings were like microscopic metal splinters and dug into the skin in my hands like fiberglass. I really wish I was wearing gloves when I was Dremeling and swept the floor as soon as I was done!

Hopefully this will help the next person who is staring down a stubborn crank sprocket!

 

Thanks for the info!

 

I also had a rough time getting that crank sprocket off my r53. What finally did it was lots of torch heat... and here's the puller that I used.

I lost a few teeth on the first attempts. Lot's of torch and it worked

 

Here because I'm currently doing this work on my 2005 R50 with 160K miles on the clock. This is exactly the right kind of puller to use (the one pictured above by Roger Coulson), but secure it tight before you start with a hand tool (so it doesn't slip and break teeth off), and then use an air or electric impact gun and it will work its way right off. No need to heat the sprocket. There's no way I'd attempt this job without an impact gun!

 

Suggestion: Always use Grade 8 bolts for this type of removal. They won't bend.