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Engine Front Cover alternator mount - Shaft Seal reinstall

zoomtoob

New member
Quick question as i tried but could not find a post to answer this:

when reinstalling the engine front cover/alternator mount over the timing chain, can i add the seal after the cover is bolted on and in place with sealant? trouble is - in trying to algin things, I will ruin the shaft seal. not a lot of room to work in there with the sustension etc in the way.

thanks in advance.
 
That was tricky to do when I had the engine out. But, yes the seal can be installed over the nose of the crankshaft after the cover is in place. BUT:

1. the seal needs to be protected.
2. the seal lip needs to curl inward.

I found that an old fashioned black Kodak 35mm film can with the bottom cut out makes a perfect sleeve to put the seal around, slide over the crankshaft nose, and allow the seal to be driven into place.

So go find, beg or borrow a black Kodak 35mm film container.

Then it becomes a choice: either install the seal and use the film can to protect it while installing the cover, or install the cover and use the fulm can to protect the seal while installing the seal.
 
I installed my seal after the cover was in place. I used a small section of mylar engineering film from work and wrapped it around the shaft so that the groove was covered. I then formed the lips of the seal so they curved the proper direction and oiled the lip well. Slid it on to the shaft over the mylar and tapped it into place with a section of pvc pipe. Finally I removed the mylar and let the seal sit for a day or two so it would form properly against the shaft. No leaks so far.

35mm negative film would work instead of mylar.
 
You guys are excellent. only thing is I had not turned on notifications for replies to this post so did not get the good word til just now. had to figure it out over the weekend and the seal is in fine. the orientation and preforming were tough to find but I did and thought I'd post to the MOA also. I hope this gets found by those who need it.

installation of the crankshaft seal in the alternator mount cover
other keywords - hall effect sensor, 3-bond 1209, "11 5 680", poly v-belt pulley

Good lluck getting the cover out with the motor on the bike, it is a bit of a trick. I had to jack up the front suspension and move the battery and ECU and then back the alternator out of the way to pull it out... It is a good time to clean out the gunk that can accumulate on top of the engine. mine is a 99 so i got to clean up and replace some of harnessing in there.

I used a piece of 1-liter water bottle to make the sleeve. it was already curved and overlapped itself. this allowed me to make it conical to slide the seal over the shaft end. makes sense and less than $54 from MAX for the 11 5 680 tool. see the pics below. the kodak film vial has to be perfect. Thanks again.

FYI - apparently the seal is hyrodynamic and will redirect oil back into the engine (via concentric grooves on the inside lip) as the shafrt rotates and oil tries to escape out past the lip of the seal.

as you can see from the second pic, the seal has to be a little warm and preformed by hand so the inside (brown) lip is pointing in towards the engine. I have read of others trying to install the seal with the brown side out or with the brown lip pointing out and away from the engine... the black side goes out and the arow on the black side shows alignment with engine rotation (clockwise)

front side of seal (faces out) showing the arrow at 11 o'clock -


back side of seal showing lip alignment and the grooves that keep oil inboard. (This one was damaged when i pulled off the cover. it's only $15 so... that was also the reason i installed it after the cover was remounted.)
Seal backside.jpg

I then slid the formed seal over the tool so it can then be slid over the main shaft. Then you slide the seal from the plastic "tool" onto the smoothed larger-diameter part of the shaft. you can remove the "tool" before you finally drift the seal into place flush with the housing. I used a 32mm socket to do this but be careful here - use a small block of wood so you don't drift the seal past the flush edge of the engine cover. also the manual called for 3-bond 1209 - no way to get that so i used permatex black oil-resistant gasket adhesive. clean the mating surfaces well but don;t use a razor blade as it may scratch it. something less agressive works well along with patience.

for the actual cover reinstall, I used a very thin coating of gasket adhesive on the engine side and then brought the cover into place and added the shaft seal later. This was done to avoid damaging the seal when jimmying the cover into position. BTW - good luck with the oil tube running down the side of the cover. I had toi disconnect it at both ends and jiggle it out of the way to do all this.

After all that - it is in, clean and good to go. i have a couple of other pics to add later. Thanks to Paul and WV for the help!
 

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