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I screwed up!!!!!!!!!

Posted: Sun Jul 04, 2010 9:46 pm
by BIGGUYLITTLESCOOTER
Can you re-thread the output shaft. I didn't get the front pulley on correct, started scooter for less then a second heard the noise and shut it off..............To late the threads are ruined on the output shaft. Please tell me I don't have to replace the crank, please.........

Re: I screwed up!!!!!!!!!

Posted: Sun Jul 04, 2010 9:49 pm
by mr pibbs
errrr...

Re: I screwed up!!!!!!!!!

Posted: Sun Jul 04, 2010 10:53 pm
by martynkim
My crystal ball sees lots of cussing in your future. You might be able to go to a smaller diameter. Worth a shot sounds like you have very few options. :|

Re: I screwed up!!!!!!!!!

Posted: Mon Jul 05, 2010 3:36 am
by ae86guy
get a tap and die kit and tap it to one size smaller should b sweet i stripped the thread in carb main bolts i tapped them out to one size over and its mint

Re: I screwed up!!!!!!!!!

Posted: Mon Jul 05, 2010 7:29 am
by evilone
You said you didn't get the pulley lined up right, hopefully you're not talking about the splines on the crank. Threads will be tricky with a 50/50 chance of making it work.

Re: I screwed up!!!!!!!!!

Posted: Mon Jul 05, 2010 10:19 am
by BIGGUYLITTLESCOOTER
evilone wrote:You said you didn't get the pulley lined up right, hopefully you're not talking about the splines on the crank. Threads will be tricky with a 50/50 chance of making it work.
Splines are okay but threads are f****d.

Re: I screwed up!!!!!!!!!

Posted: Tue Jul 06, 2010 4:22 pm
by elitedio
If it is a ten mm you might be able to rethread to a 3/8" SAE nut. It is just a bit smaller.

Re: I screwed up!!!!!!!!!

Posted: Fri Jul 09, 2010 11:39 pm
by Chaostoy
I know this is old, but simply wished to add to it from experience. I also had issues with putting on the drive belt, and didn't get the drive face on the crank splines all the way, and trashed the threads. I got a 10mm-1.25 die from Ace Hardware, and got the nut of the same size from Autozone, and cut new threads in today. Make sure you start the die totally straight! This die went on perfectly for me, and actually with no force really. I think it is the same cut as factory. Hope this helps.

Re: I screwed up!!!!!!!!!

Posted: Sat Jul 10, 2010 1:20 am
by Bear45-70
Chaostoy wrote:I know this is old, but simply wished to add to it from experience. I also had issues with putting on the drive belt, and didn't get the drive face on the crank splines all the way, and trashed the threads. I got a 10mm-1.25 die from Ace Hardware, and got the nut of the same size from Autozone, and cut new threads in today. Make sure you start the die totally straight! This die went on perfectly for me, and actually with no force really. I think it is the same cut as factory. Hope this helps.
If the threads were 10 mm originally, all you did was clean off the buggered parts, but a bunch of thread material is gone and the threads will be weaker, a lot weaker. They will have less ability to hold the torque and will fail not to far down the road. You need to drop down one size and in this case that is the 3/8 SAE. Dropping to 8 mm makes the shaft to small.

Re: I screwed up!!!!!!!!!

Posted: Sat Jul 10, 2010 9:35 am
by Chaostoy
Good point, but they seemed really strong when I was putting my weight on the ratchet to snug it. I'll keep an eye on it, and if this belt shreds too, then I'll know what's up. Thanks bear. :)

Re: I screwed up!!!!!!!!!

Posted: Sat Jul 10, 2010 1:10 pm
by Bear45-70
Chaostoy wrote:Good point, but they seemed really strong when I was putting my weight on the ratchet to snug it. I'll keep an eye on it, and if this belt shreds too, then I'll know what's up. Thanks bear. :)
Torque Wrench! How many times does this have to be said. You WILL screw up the threads if you don't use a torque wrench. Maybe not the first time but it will happen and then you will have a mess. The other thing is that you ALWAYS start every nut or bolt by hand, never with a wrench. Cross threading is the major problem when working with small nuts and bolts, especially with steel bolt threads into aluminum crankcases threads.

Re: I screwed up!!!!!!!!!

Posted: Sat Jul 10, 2010 3:28 pm
by Chaostoy
Ok man, I'll get one next paycheck, don't eat me bear! :oops:
Thanks for the words of experience though for real.

Re: I screwed up!!!!!!!!!

Posted: Sat Jul 10, 2010 3:45 pm
by martynkim
I just use loctite. I don't own a torque wrench. Seems to hold well. :nervous:

Re: I screwed up!!!!!!!!!

Posted: Sat Jul 10, 2010 4:18 pm
by Bear45-70
martynkim wrote:I just use loctite. I don't own a torque wrench. Seems to hold well. :nervous:
The torques spec is to put a certain amount of pressure on the item being held. Loctite does not do anything but hold the bolt or nut in place. The pressure is especially important when holding a flywheel to a taper. The key is to align the crank and the flywheel. the pressure holds the two together. The there are splines, you need to hold them together and in place or the splines will wear and fail.

Get one of these;

http://www.harborfreight.com/1-4-quarte ... -2696.html

and one of these and you will be covered.

http://www.harborfreight.com/3-8-eighth ... h-807.html

Re: I screwed up!!!!!!!!!

Posted: Sat Jul 10, 2010 4:53 pm
by zuphilius
Bear45-70 wrote:
martynkim wrote:I just use loctite. I don't own a torque wrench. Seems to hold well. :nervous:
The torques spec is to put a certain amount of pressure on the item being held. Loctite does not do anything but hold the bolt or nut in place. The pressure is especially important when holding a flywheel to a taper. The key is to align the crank and the flywheel. the pressure holds the two together. The there are splines, you need to hold them together and in place or the splines will wear and fail.

Get one of these;

http://www.harborfreight.com/1-4-quarte ... -2696.html

and one of these and you will be covered.

http://www.harborfreight.com/3-8-eighth ... h-807.html
And remember, don't use the top or bottom 10% of the torque value on the wrench, you won't get an accurate torque.

Sorry, my aviation mechanic training kicked in.

Thanks for the link Bear, I might have to replace my crappy 3/8" Craftsman wrench. I have a Snap-on 1/4" 0-150 inlb that couldn't be calibrated for work on aircraft, got that free, they were tossing it away.