Burman Box Oil/Grease Leak

Martyn Goodwin

Martyn Goodwin

Well Known and Active Forum User
Non-VOC Member
What are the suggested cures for making the gear change shaft, where it passes through the outer case of a Burman Gearbox, oil tight?

Here is the mess of ejected semi-fluid grease I currently have, after 1 2 hour 60 mph run! It was clean at the start.

Martyn
DSCI0081b.jpg
 
R

redbloke1956

Well Known and Active Forum User
Non-VOC Member
Hi Martyn, admittedley I haven"t ridden the Comet very much due to "issues" but while overhauling the gearbox I noticed that the gearchange shaft had a little endplay so I fitted an O ring between the case and the "spring box" (I think that is what it is called) This initially makes changing a little stiffer but loosens up with use.
Kevin
 
Martyn Goodwin

Martyn Goodwin

Well Known and Active Forum User
Non-VOC Member
Just checked my box and there does not seem to be any endplay on the gearchange shaft - but that does not mean there is no slop between the spring box and the gearbox case itself. Blowed if I know how to measure that one!

I am just toying with the idea of machining a recess on the inside face of the Control Lever Bushing PR50-C054 (thats the bit the gear lever shaft passes through) and installing a oil seal, like the sort of thing that seals the dynamo shaft on a Comet - that seal is E224. I know the E224 will not fit, but I suspect any decent bearing shop may be able to come up with one that will.

But as I say - I'm just going through the thought processes at present.

Martyn
 
vibrac

vibrac

Well Known and Active Forum User
VOC Member
Mr Kemp did an article on uprating a Burman box in MPH about 20 years ago seals and all. If somebody could find that it would stop a lot of wheels being re-invented. But then that seems to apply to many of these threads, after all a lot of clever blokes (many now pushing up daisies) have spent over 70 years 'improving' the Vincent. never in the history of forums were the words "nothing new under the sun" more appropriate.
A compulsory reading of 40 years on and it sequel may be a good idea for some contributors. (not Martyn I hasten to add:eek:)
 
greg brillus

greg brillus

Well Known and Active Forum User
VOC Member
Hey there Martyn, I think you will find you have 2 areas to seal off. The larger hollow shaft that the Gearlever mounts to and also the shaft through the middle, that the gear indicator mounts to. I think the easiest way is to machine grooves or recesses and fit "O" rings as per what Kevin suggested. Be mindfull that too much tension on the shafts verses "o" ring may cause the gearshift function to become too stiff. The "O" rings don't need a high interferance to seal alright, given there is no pressure......Greg.
 
Martyn Goodwin

Martyn Goodwin

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Non-VOC Member
I wonder if anyone can tell me exactly which MPH numbers I need to go searching for.

I have looked in "40 years on"; "Another 10 years" and also in the "MPH Index, 1989" but have not been able to identify anything relevant.

Martyn
 
vibrac

vibrac

Well Known and Active Forum User
VOC Member
It was just in an MPH my guess would be the 70's which was when Ron was at his most prolific.or perhaps while he was hon technical officer
It would be a good project to scan/hold all the MPH in an computer file for members only or perhaps a more volunteer possible task, just the indexes for all the MPH's
 
Martyn Goodwin

Martyn Goodwin

Well Known and Active Forum User
Non-VOC Member
I have a MPH index, produced in 1989 by Nick Hunter - it is/was a VOC publication; it seems to cover MPH's from Jan 1949 (#1) up till July 88 (#474), but as the title suggests, its an index only.

Martyn
 
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