Author Topic: Crank not rotating  (Read 1978 times)

Offline alexdecker

  • SOHC Member
  • Posts: 204
    • View Profile
Crank not rotating
« on: May 06, 2022, 04:51:15 PM »
Just connected to the halves of the bottom end. My crank seems to be stuck though. Checked the gears before installing and they were fine.

Is it supposed to be able to rotate free at this point?

Offline Bryanj

  • Grogu
  • *
  • Posts: 8932
    • View Profile
Re: Crank not rotating
« Reply #1 on: May 06, 2022, 05:09:10 PM »
Something is put togerher wrong, should turn easy

Offline alexdecker

  • SOHC Member
  • Posts: 204
    • View Profile
Re: Crank not rotating
« Reply #2 on: May 06, 2022, 05:24:58 PM »
It happens when I torque the 10 main bolts down. 17 foot pound is my spec. Why is this??


Offline alexdecker

  • SOHC Member
  • Posts: 204
    • View Profile
Re: Crank not rotating
« Reply #3 on: May 06, 2022, 05:35:06 PM »
Just went down to 14 foot pound. Still seizes when I tighten.

Offline Oddjob

  • Grogu
  • *
  • Posts: 5475
    • View Profile
Re: Crank not rotating
« Reply #4 on: May 06, 2022, 05:46:18 PM »
Wrong shell in wrong location?

Check nothing under the shell making it stand prouder.
Don't play stupid with me, I'm better at it

Offline McCabe-Thiele (Ted)

  • SOHC Master
  • Posts: 2323
  • 07505030740
    • View Profile
Re: Crank not rotating
« Reply #5 on: May 06, 2022, 05:48:12 PM »
My thoughts.
1.Is it in neutral.
2.Is the cam chain free.
3.Did you Plastigauge the mains.
4.Are the conrods free.
Honda CB400 four super sport

Offline alexdecker

  • SOHC Member
  • Posts: 204
    • View Profile
Re: Crank not rotating
« Reply #6 on: May 06, 2022, 05:57:00 PM »
Everything is free. I didn’t plastic gauge, as I marked the location of each bearing and put them back in the same place.


Offline murdock

  • SOHC Member
  • Posts: 195
    • View Profile
Re: Crank not rotating
« Reply #7 on: May 06, 2022, 06:19:27 PM »
How big was the hammer you used to remove the rotor? ......
I'm scared of you. ;D
 

Offline Bryanj

  • Grogu
  • *
  • Posts: 8932
    • View Profile
Re: Crank not rotating
« Reply #8 on: May 06, 2022, 06:21:05 PM »
You did put the shells into the cases with cases and back of shells dry didnt you,mixing up shells would not normally lock it up, i have built with all tightest shells before now with no problem.
Primary shaft needs to be fitted and cam chain free but should turn by hand.
You havent tried to miss match cases?

Offline Johnny4428

  • SOHC Pro
  • Posts: 797
    • View Profile
Re: Crank not rotating
« Reply #9 on: May 06, 2022, 07:20:27 PM »
Crank seal located correctly?
1952 Cymoto on Triumph bicycle.
1961 Matchless G3
1978 Honda CB550K3.
1999 ST1100 Pan European 50th Anniversary.
1975,1980,1984,1986 Honda C90’s
1973 Honda CB750K3

Offline Oddjob

  • Grogu
  • *
  • Posts: 5475
    • View Profile
Re: Crank not rotating
« Reply #10 on: May 06, 2022, 07:23:37 PM »
A black in a yellow location might lock it Bryan but I was more thinking of something behind the shell making it bind onto the crank.
Don't play stupid with me, I'm better at it

Offline McCabe-Thiele (Ted)

  • SOHC Master
  • Posts: 2323
  • 07505030740
    • View Profile
Re: Crank not rotating
« Reply #11 on: May 06, 2022, 07:33:34 PM »
I assume the upper half case was upside down when you started assembly. Did the Crank rock freely when sat in the Crank mains with assembly lube applied? I am assuming it not significantly different to a 400/4. I
Can the Crank be fitted in the wrong way round.
Honda CB400 four super sport

Offline alexdecker

  • SOHC Member
  • Posts: 204
    • View Profile
Re: Crank not rotating
« Reply #12 on: May 06, 2022, 07:40:03 PM »
How big was the hammer you used to remove the rotor? ......
I'm scared of you. ;D

Oh god, I hope I didn’t do what you are referring to!

Offline alexdecker

  • SOHC Member
  • Posts: 204
    • View Profile
Re: Crank not rotating
« Reply #13 on: May 06, 2022, 09:12:05 PM »
I assume the upper half case was upside down when you started assembly. Did the Crank rock freely when sat in the Crank mains with assembly lube applied? I am assuming it not significantly different to a 400/4. I
Can the Crank be fitted in the wrong way round.

I did exactly that. Pretty sure I mounted it the right way. And yes, it moved freely.

Offline alexdecker

  • SOHC Member
  • Posts: 204
    • View Profile
Re: Crank not rotating
« Reply #14 on: May 06, 2022, 09:16:04 PM »
You did put the shells into the cases with cases and back of shells dry didnt you,mixing up shells would not normally lock it up, i have built with all tightest shells before now with no problem.
Primary shaft needs to be fitted and cam chain free but should turn by hand.
You havent tried to miss match cases?

I only lubricated the crank contact side of the shells. I fear that the crank might have gotten bent when I put the hammer to the rotor puller to get the rotor off.

Still - I didn’t have the crank in a vice when I did that, so it could move freely, and the rotor puller and rotor contact point seems too small to be able to bent the crank like that. But it’s the only possible thing I can think of happened. Everything else is in its right place. When I torque it down with my drill, it still rotated freely. But with the torque wrench it seizes up 😕

 

SimplePortal 2.3.5 © 2008-2012, SimplePortal