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In the depths of the crankcase

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In the depths of the crankcase

Posted by John Pullen-Appleby at March 14. 2017

Hello All,

I split the crankcases this evening-- or rather I tapped bits of wood and crank shaft ends with various soft mallets and scratched my head until I had found the last screw--there are lots of them and some are in--to me used to Triumphs, in funny places.

 

Compred to Triumph cams--the Navigator's seem huge and appear unmarked.

 

The crankcases were full of black tar like compounds fit to attract frakers.  There was a paper joint in between the faces and it does not seem that Mr Chisle has been there.

 

The pistons and bores looked very clean--the pistons are shiny.  One head stud  was loose--half undone and seemingly glued on with some superglue like stuff.  I took it out and run a 5/16 BSW tap down the hole and it went back and seems fine now  (once free of debris the thread was OK  was was going om there i don't know.

 

I'll post some pictures--especially as I am baffled by an aspect of the gear box.

 

Cheers

JPA

Re: In the depths of the crankcase

Posted by John Pullen-Appleby at March 15. 2017

Hello again,

I have got received a manual in the post--probably one of the ones on Ulrich's links but I am glad I bought a hard copy as I am reading it in a class (I teach in a college) while the students do a test.  I have just seen that the nut that holds on the front sprocket is a LH thread.  I wondered when tying it tentatively this morning.

 

I have also noticed that the pivot pin for the selector forks screws into then back of the gearbox.  I have not seen that on Triumph and BSA boxes  (or left hand sprocket nuts for that matter).

 

What I cannot fathom is how to take the main-shaft out of the inner cover.  I think the instruction--remove the retaining ring has something to do with it--there is the older type clutch actuation lever over the top and I am assuming that a nut lays underneath.

 

Any advice gratefully received

 

JPA

Re: In the depths of the crankcase

Posted by Ulrich Hoffmann at March 15. 2017

John,

you´re right underneath that clutch actuator and lockring is the nut for the mainshaft. Been there, done that but can´t remember if it is a RH thread or a LH. Leave the chain sprocket on an block it with a piece of chain in a vice.

So, how many students did cheat in that test while you were reading Norton literature?

Re: In the depths of the crankcase

Posted by John Pullen-Appleby at March 16. 2017

Previously Ulrich Hoffmann wrote:

John,

you´re right underneath that clutch actuator and lockring is the nut for the mainshaft. Been there, done that but can´t remember if it is a RH thread or a LH. Leave the chain sprocket on an block it with a piece of chain in a vice.

So, how many students did cheat in that test while you were reading Norton literature?


Hello Ulli,

Ah it was a history sources paper assessing skills not knowledge--very difficult to cheat in.  I will post off the form to the DVLA this afternoon--let's see what the heart of British Bureaucracy can throw up.

 

How does the lock ring come off-?-It looks a bit knocked about  and looks as if it holds a cap that covers the nut on.  I cannot see the nut yet.

 

Cheers

JPA

Re: In the depths of the crankcase

Posted by Ulrich Hoffmann at March 16. 2017

Thanks John, had to print it out an after filling in the data I scanned it in again and sent it to you. Do they list all the british owners or just the first one? At some point of her life the Commando made her way over the channel to Germany.

The correct method of removing the lockring is to use a special tool which goes into the recesses of the ring so it can be turned, the not so correct method is to use a screwdriver and hammer to knock and turn it off  ( my way...)

Re: In the depths of the crankcase

Posted by John Pullen-Appleby at March 16. 2017

Previously Ulrich Hoffmann wrote:

Thanks John, had to print it out an after filling in the data I scanned it in again and sent it to you. Do they list all the british owners or just the first one? At some point of her life the Commando made her way over the channel to Germany.

The correct method of removing the lockring is to use a special tool which goes into the recesses of the ring so it can be turned, the not so correct method is to use a screwdriver and hammer to knock and turn it off  ( my way...)

Hello Ulli,

I shall ask

 

JPA

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