I'm doing a timing belt change and can't get the harmonic balancer off. 
Yes I have taken the 27MM bolt out of the crank and the pulleys off.  They were also tough to get off and I noted a little bit of rust on the crank. The big three have been very helpful and do not recommend a puller since it may ruin the balancer (the book calls it a vibration dampener).  I'm considering using a puller and if it damages it I will have to replace it.

Does anyone have any other suggestions? 

Thanks,
SW Smith

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Mine slid right off. So I am guessing you are right. I would start with a lot of wd-40 or the like and soak it good for a couple of hours, lots of tapping with a hammer in all directions. I bet that at that point it won't take much of a tug with a puller to remove it. I do remember something about the damper and it's dislike for pullers a while back so
be careful and don't pull too hard.


Mark Grasser
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The outer ring of the damper is a press fit on the rubber.  Put a puller on the outer ring and you are likely to just pull it off the rubber ($300 used, $700 new) I haven't really done the thing on the damper myself, but one thing that I have found works pretty  well in these circumstances is to loosen the bolt, but not very much - maybe one turn loose.  Then pound away on the end of the bolt.  The crank doesn't care and the damper just might  work itself out.
Then loosen it another turn and keep doing it until it comes loose.  Might mangle the bolt, but the damper will come off - with a little luck.

Gary Gasey

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I had a similar one with my GTS. The harmonic balancer on the crank would not move. WD40, thin oil, de-oxidizer, rust solvent, rubber mallet, nothing helped. It took a while and by gently pushing it forward from behind using an L-shaped tool (not too much pressure, just a bit) and tapping it with the mallet left-right-left-right-left and so on, it gradually made micro movements and after half an hour it started really to move. It came off fine. There was a tiny bit of oxidation in the shaft but not even much. It is just a tight fit. I removed the oxidation with very fine sandpaper, and used copper grease to fit. I still have a bad feeling about copper and alu-steel bonding. I wonder if it is a good idea to do so but I had no alternative at the time.

regards

Theo

http://928gts.jenniskens.eu