G39AS and G33 assembly

Brian Thompson

Well Known and Active Forum User
Non-VOC Member
Hello Everyone,
I have a meshing problem with the above mentioned gearbox parts. Now in the parts defence I haven't installed the gear set.These gears ( G39as and G33) are new. I have pressed the G33 into the new 5 speed gear selector plate. With G54 screwed in and I push up on the Selector plate the mesh is very notchy when turned. Am I being too judgemental with out assembling the whole gearbox?
I haven't glued the engine cases together at this stage in anticipation of there being something wrong. The first time is always the hardest.
If I put the old G33 and plate against the new G39as it turns nicely.
Please your thoughts would be most welcome? I have ordered the "Know Thy Beast" book , but getting in early I thought I'd see what I can get done.
Also something to ponder. When the new gears are assembled the detent position lines up on first and 5th perfectly. But when I put the old G33 in there ( against the new G39as) it doesn't rotate enough to line up the detent notch. I hope that makes sense. Something to watch if mismatching old and new parts. If the stop dowel was removed this wouldn't be an issue.
Cheers
brt650
 

Brian Thompson

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Non-VOC Member
Well I have jumped ahead tonight. I have installed the 5 speed gear clusters. I'll take the G2 to work tomorrow and heat it in the hot bath and install the new bearings. And detent holder.
Cheers
brt650
 

Bill Thomas

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VOC Member
Hello brt650, Look up 5 speed boxes on this forum, Only a short while ago there was a bit about if you have to alter the amount the plate moves, One said you don't have to then some body said you do if it was a Terry Prince one, Good Luck Bill.
 

clevtrev

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VOC Member
Until you have assembled the box completely, you`ll have no idea where the camplate will finish up, as regards to the mesh, as it sits on top of the selector forks.
 

Monkeypants

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Paul Richardson's book has a section on assembly of the gearbox. " Know Thy Beast" has much useful information , but from my reading , it is not aimed directly at the mechanic doing the assembly work. His book gives good detail about the construction of the components and some common problems to watch for, but is not like a Mechanic's Shop manual. Richardsons book is closer to a shop manual.
You might want to get both.
on edit- just looked thru the "Instruction Sheets, Series BC&D", it has a much more comprehensive section on gearbox assembly than Richardson. I would add this publication to your shopping list as well. I think the Spares Co. has both items at relativley low cost.
Glen
 
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Brian Thompson

Well Known and Active Forum User
Non-VOC Member
Thank you for your replies.
I have assembled the G2 today and will try to assemble it tonight.
Is it OK to continue with this topic? Or do I keep this assembly process to myself?
I don't want to annoy or waste peoples time when they have probably done this work before.
Cheers
brt650
 

Bill Thomas

Well Known and Active Forum User
VOC Member
Hello Brt, That is what the Forum is for, Please don't be put off, I think some people have not replied because it was only a few months ago a lot of it was talked about, Good Luck, Bill.
 

Brian Thompson

Well Known and Active Forum User
Non-VOC Member
Well I have successfully assembled the gearbox and it operates quite freely. And now I have stripped the gearbox apart and packed away.
I'll split the cases now and get new engine studs/nuts and goo for re-assembly.
By then, Know Thy Beast should be here.
 

Bill Thomas

Well Known and Active Forum User
VOC Member
Hello Brt, I think there are at least 2 types of 5 speed boxes, And I don't think there will be anything in Know Thy Beast about any of them, It was too long ago. Cheers Bill.
 

vibrac

Well Known and Active Forum User
VOC Member
Ther was an early issue about a spacer on one of the shafts I think a search of this forum for "surtees 5 speed" or "Quaife" would dig it up
other than that it seems to have been a good product cerainly ours did 3 of 4 seasons racing and Ben did not use a clutch going up "under pressure"
(we had Newby belt drive/clutch and I made a moddified special G61 but otherwise all bits off the shelf)
 
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