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Lower balance shaft spins freely, binds when pulley is torqued on

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Old 01-16-2016 | 01:31 AM
  #31  
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Originally Posted by odonnell
I need to amend my previous post(s), the mylar seal does NOT go between the camshaft itself and the rear cover. I was thinking of the O-ring, it's been a few beers before we did all that. According to the WSM it goes between the rear cover and the retainer (the part with the flange at the back). The latter spins with the cam obviously. As long as you follow that blow-up you'll be fine. I'm pretty sure we put it in the right spot, if not that was an oversight and an overhang from the first time we put it together, where it wouldn't fit together. Of course the mylar seal is too thin to affect how it goes back together.
Actually you were right the first time. We both were. Turns out the diameter of the rear cam gear cover is larger than the snout of the cam where the mylar washer sits, so it doesnt matter whether the onion skin seal goes on first or the rear cam gear cover goes on first; as long as they are the first two things to go on the, the rear cover slips right over the onion skin seal anyway.

After that the race/retainer goes on on the cam snout with the flange against the mylar washer. It will snug the mylar washer up against the shoulder on the cam snout and the flange will snug up against the rear timing gear cover. After that the cam seal gets pressed on around that race, and then the woodruff key and the cam gear go on. So we had it right the first time, just as you said.


Cheers everyone, thanks SO much for the help. I have both of my cam towers and both balance shafts on the NA sealed correctly now.

Wish we could all sit down one day and have a beer, this place and the people here are invaluable.
Old 01-16-2016 | 01:36 AM
  #32  
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EXTRA big thanks to Porscheru for the diagram which helped clear things up for me, and to Charlie for making me realize I'm an idiot and I assembled the damn thing incorrectly. Owe both you gents a beer!

Michael, owe you many beers sir!
Old 01-16-2016 | 01:50 AM
  #33  
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Similar problem few days ago. Resealed lower balance shaft cover. Putting front cover on over shaft, it would bind losing all front to back play and rotation as I tightened one of the bolts. Eventually, by gently rotating the shaft back and forth to judge when it started binding, I would tighten one of the 3 bolts until binding then back off and move to another bolt. Sometimes only half a turn would cause bind but rotation would return when backed off and would move to the next bolt. Took a while. Eventually had all three bolts torqued down, pulley on, free rotation with no binding. Hope this helps.
Old 01-16-2016 | 02:42 AM
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Originally Posted by Martin's928
Similar problem few days ago. Resealed lower balance shaft cover. Putting front cover on over shaft, it would bind losing all front to back play and rotation as I tightened one of the bolts. Eventually, by gently rotating the shaft back and forth to judge when it started binding, I would tighten one of the 3 bolts until binding then back off and move to another bolt. Sometimes only half a turn would cause bind but rotation would return when backed off and would move to the next bolt. Took a while. Eventually had all three bolts torqued down, pulley on, free rotation with no binding. Hope this helps.
My issue actually had nothing to do with what you are describing, though I've heard similar accounts from other guys while I was researching my issue. Not sure what causes that problem, but in my case it was improper assembly.

Please note too that I was able to get both shafts spinning freely despite both being assembling incorrectly, so the fact that you were having an issue and now it seems to be OK is not indicative that everything is actually alright. You may want to take the time and rear through this entire thread since it has some very good information in it that may be very pertinent to your situation.

With everything properly assembled, it absolutely should not bind and shouldnt be that finicky with regards to how you torque the bolts up. As I learned today, there is only one correct way to assemble them of course; but as it turns out there are actually multiple different wrong ways so it's quite easy to make a mistake as I assembled my shafts 3 completely different wrong ways before I discovered how they are supposed to go together.
Old 01-16-2016 | 10:13 AM
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Ok! Thanks on that! I'll go back and check my install.

Realize your issues were different (actually, missed that your shaft would still rotate with the pulley off), but on a gut level I feel there's a common thread there. I'll go back and make sure I got it right….



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