G: Gearbox (Single - Burman) Comet Gearbox

G

Graham Smith

Guest
Evening all - on my Comet, I have the following gearbox…

It has the code I BAP M 26 V cast underneath.

IMG_3181.JPG


Ages ago I bought the following gearbox at an autojumble, and that has the code

I BAP M 26 VAF cast underneath.

Does anyone know the difference?

IMG_3185.JPG
 

Attachments

  • IMG_3180.JPG
    IMG_3180.JPG
    142.7 KB · Views: 28
  • IMG_3186.JPG
    IMG_3186.JPG
    198.5 KB · Views: 28

chankly bore

Well Known and Active Forum User
Non-VOC Member
The both gearbox shells MAY be correct. The prefix G97 is correct for the Meteor/Comet, assuming it hasn't been monkeyed with. I don't know what the G40 prefix was used on, but main things that seem to differ are mainshaft lengths, clutch centre bosses and, critically, the widths and locations of the top and bottom mounting lugs. To establish a datum, measure both of these from the face of the output bearing register on the G97 box and post them here. I'll confirm them with a known original if you like. A good chance that all the gears will be the same, but I have found a 34 tooth output gear in my travels! I believe "V.A.F." may have something to do with Vickers Aluminium Foundry, can anyone shed light? The best foundryman I ever met did his apprenticeship at Vickers Ruwolt here in Melbourne in the days when we actually made stuff in this country.
 

chankly bore

Well Known and Active Forum User
Non-VOC Member
By the way, Graham, be careful of the 5/16" x 26 t.p.i. adjusting bolts in the bottom lug. They are usually hammered over at the inner ends and need cutting off, slotting, dressing and screwing IN from the outside to remove them. If these threads are already oversized or stuffed the best repair are accurate 7/16" B.S.F. steel inserts Loctited in carrying the right original thread. Sorry if I'm teaching Grandma to suck eggs, but someone may benefit from this trickery.
 

vibrac

Well Known and Active Forum User
VOC Member
I think most of my Burman bottom threads are 3/8" whit I know I did some but some were handed down like that. After all the years the direction of adjusting is still counter intuitive and I always take a moment to remind myself the cross bolt does not move, am I alone in that?
 
Top