Author Topic: It won't go in - primary shaft that is!  (Read 412 times)

Offline billdn

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It won't go in - primary shaft that is!
« on: May 14, 2022, 05:36:12 PM »
Rebuild takes place slowly and have just bonded crankcase together and all torqued up nicely.
However when fitting the primary shift via oil pump side as advised it won't go in .I've fitted a new primary chain and it's as if it's too tight but only by a gnats ! Misalignment is so small but enough to only get shaft through first bearing.
Any ideas?
Iffy primary chain, albeit DS ?
Horrible feeling cases need to come apart for closer look, anyone had similar when fitting new primary chain. Although rotates crank fine if using nut on alternator end .

Offline McCabe-Thiele (Ted)

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Re: It won't go in - primary shaft that is!
« Reply #1 on: May 14, 2022, 05:55:44 PM »
I had a similar issue on my 400 - it was the primary chain at the Crank end not sitting fully on the teeth After a lot of rocking the Crank to and frow by a few degrees it suddenly fitted into place. Walk away go back it should drop into place. On my previous Crank case halves it went in easily first time but the last time it was fiddly.
The case was upside down whilst doing this.
« Last Edit: May 14, 2022, 06:34:41 PM by McCabe-Thiele (Ted) »
Honda CB400 four super sport

Offline Oddjob

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Re: It won't go in - primary shaft that is!
« Reply #2 on: May 14, 2022, 06:45:24 PM »
A new primary chain and new damper rubbers will always mean a tight fit when reassembling. Sometimes you need to lever against the shaft through the sump opening, be careful where you lever though. It only needs a small amount of movement for it to suddenly drop into place. I found removing the oil pump so you can see the end of the shaft as it comes toward the bearing gives you an idea of which direction you need to move the shaft in order for it to line up.
Don't play stupid with me, I'm better at it

Offline billdn

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Re: It won't go in - primary shaft that is!
« Reply #3 on: May 16, 2022, 09:06:54 AM »
 Here's guys, bit of wiggling and jiggling and all moving freely.

Offline Oddjob

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Re: It won't go in - primary shaft that is!
« Reply #4 on: May 16, 2022, 12:38:23 PM »
Are you drunk Bill?
Don't play stupid with me, I'm better at it

Offline billdn

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Re: It won't go in - primary shaft that is!
« Reply #5 on: May 16, 2022, 02:56:15 PM »
To hell with predicted text, meant Cheers  :-\

Offline Laverdaroo

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Re: It won't go in - primary shaft that is!
« Reply #6 on: May 16, 2022, 04:27:45 PM »
Mornings are the invention of the devil!
1977 CB550F (new money pit!!)
2002 VFR800 VTEC
1977 CB400F (current money pit!)
1998 Ducati 748\853 conversion
1980 ish CB750KZ in a billion bits (need to get rid!!)

 

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