Author Topic: Gearbox issues ongoing - A7 Plunger  (Read 928 times)

Offline namloop

  • Moving Up
  • **
  • Join Date: Apr 2012
  • Posts: 37
  • Karma: 0
Gearbox issues ongoing - A7 Plunger
« on: 25.10. 2012 10:22 »
I haven?t made much progress in my gearbox reassembly, so I decided to go back to the beginning.
I have inserted the cam plate and plunger and marked off the neutral notch, then setting the plate into position winding the cam plunger in to hold it in place.
I have placed the inner cover over the studs with the selector in the horizontal position, which I didn?t disturb in the overhaul, onto the main casing.
I have not replaced the 2 shafts or cogs at this stage
The selector does not engage and basically flicks over the surface of the camplate notches.
If I remove the cam plate plunger it will move the camplate but it jams as it spins it nearly 180 degrees.
What I cannot fathom is how the unit is not going back together and there is this physical distance between the selector and the edge of the cam plate when I know the gearbox was selecting perfectly before I opened it up.
There must be something very simple I am overlooking.
Thanks for any ideas in advance.

Stephen - Gold Coast Australia.

Online Brian

  • Wise & Enlightened
  • *
  • Join Date: May 2007
  • Posts: 1806
  • Karma: 43
  • Mt Gambier, South Australia.
Re: Gearbox issues ongoing - A7 Plunger
« Reply #1 on: 25.10. 2012 10:43 »
Seems a bit odd since it was working ok before. Put the gears in the neutral position when you reassemble the box.

Put the cam plate in and screw the detent plunger in until about one or two threads are showing from the locknut. Hold the selector fork about level as you slide the inner cover on. Now if at this stage it doesnt engage with the cam plate something is not right.

One thing to check is the "claw" on the end of the selecter arm. That claw is spring loaded, it should take a bit of pressure to move it up or down. Its not unheard of for the spring behind the claw to break or become too weak.

Offline duTch

  • Ricketty Rocketty Golden Flashback
  • Wise & Enlightened
  • *
  • Join Date: Oct 2011
  • Posts: 4528
  • Karma: 41
Re: Gearbox issues ongoing - A7 Plunger
« Reply #2 on: 25.10. 2012 11:43 »

 Steph, I'm a bit confused as to which is engaging/not, the camplate only needs to rotate about 180˚ or a bit less?
 As Brian says check the pawl springs?
 
I'm assuming the camplate is installed so the pawls on the back side are facing out? don't under stand this bit
Quote
there is this physical distance between the selector and the edge of the cam plate
...?

Sorry, but they're fairly fool-proof?
 What part of the Goldy you on? I'm just up in Brizzo, can come and look at it if you get stuck?

 Gatton swap meet is on this saturday too if you need stuff?
Started building in about 1977/8 a on average '52 A10 -built from bits 'n pieces never resto intended -maybe 'personalised'
Have a '74 850T Moto Guzzi since '92-best thing I ever bought doesn't need a kickstart 'cos it bump starts sooooooooo(mostly) easy
Australia

Offline namloop

  • Moving Up
  • **
  • Join Date: Apr 2012
  • Posts: 37
  • Karma: 0
Re: Gearbox issues ongoing - A7 Plunger
« Reply #3 on: 26.10. 2012 06:39 »
Brian/Dutch
Thanks for you advice so far
Dutch - near Burleigh Heads - can't make this weekend

The camplate has the tracks on the correct side so I assume it is installed correctly.
I have checked the claw and the spring is firm holding itself in the level position.
There is no apparent damage to any part.
When assembled there are (3) segments on the cam I can see on the top surface of the plate.
The selector forks are engaged in the tracks and all gears change.

One thing I have noticed is the bearing in the ineer case which I have replaced required me to press the shaft through the centre but it sits against the bearing and spins freely.

Again the issue is if I am now to put the inner cover on with the claw lever installed it will only just scarpe the camplate surface and not engage into the segment.

I agree it is foolproof - somewhat!

Many thanks
Stephen

Offline duTch

  • Ricketty Rocketty Golden Flashback
  • Wise & Enlightened
  • *
  • Join Date: Oct 2011
  • Posts: 4528
  • Karma: 41
Re: Gearbox issues ongoing - A7 Plunger
« Reply #4 on: 26.10. 2012 09:33 »

 When I look at the bottom picture,(obviously upside down), it occurred to me that with no gears or shafts in there, the pawls will engage in one direction till they run out of things to engage with, but if you go back the other way, it should engage till the camplate gets to the other extremity.....= groundhog day?
Started building in about 1977/8 a on average '52 A10 -built from bits 'n pieces never resto intended -maybe 'personalised'
Have a '74 850T Moto Guzzi since '92-best thing I ever bought doesn't need a kickstart 'cos it bump starts sooooooooo(mostly) easy
Australia