Spitfire 1500 gearbox exchange.

[DougieM]

Hi. I have been stripping things down to replace the clutch but when draining the gear oil I found  two teeth plus loads of shrapnel on the magnetic plug. Is there anywhere anyone recommends for sourcing a recon gearbox? Also, is there an easy way of identifying whether it is an early or late single rail gearbox?

[Colin Lindsay]

The serial number will help identify it - I think they all read FR as a prefix but the size of the following number should let you know how far along the scale it is. 

Your closest bet for second-hand may be Chic Doig, but for recon of your own box I'd recommend Mike Papworth.

[Pete Lewis]

http://www.team.net/www/triumph/trprefix.html#Spitfirerefix tables 

from your location chic must be somewhere closer than down here 

dont think single rail had much in the way of early/late design changes 

https://www.canleyclassics.com/?catalogue=triumph-spitfire-mkiv/1500&diagram=triumph-spitfire-mkiv/1500-mainshaft-and-gears

for an off the shelf  T D Fichetts  supply much of the trade ( phone them ) £425

Rimmers  £638   

talk to Chic doig 01592 722999

Pete

[Clive]

The only differences were scroll or oil seal. I think. And I don't understand why they had scrolls at that stage....

 

Missing teeth will mean a surcharge will be made. Ouch.

[DougieM]

Thanks for the replies. Got the bell housing etc out and the serial number suggests it’s an early gearbox. Whilst I consider my options for a gearbox. There seems to be a fair bit of oil seeping along the selector which isn’t part of the recon gearbox. In the drawings I see an ‘o’ ring part 116 below, can anyone tell me if this sits inside the top cover where the selector passes through. It’s not clear on the drawing but it would serve no purpose just sitting on the shaft.

[johny]

Is your unit with OD or not as the gear change mechanism is quite different between the two. The exploded diagram above is with OD and picture 1 is without...

[Colin Lindsay]

The O ring, part 116, sits inside the alloy housing where the shaft comes through. If you really want to replace it, pick the old one out with a needle or the like once you've removed the shaft, then oil the new one and have fun getting it into place. They do fit but are inclined to be fiddly. 3-rail boxes have two so double the fun.

[Pete Lewis]

 

once you manage to unscrew the square  headed dowel bolt which on 3 rail and 1 rail can be silly tight 

i suggest you grind a small chamfer on the leading edge or the new 0 ring gets chopped by inserting the shaft

add aload of grease to help

Pete

[DougieM]

Thanks very much guys, it does have OD, I’ll fit a new o ring, Im sure that’ll solve the problem, sounds like fun. ☹️. Replaced the clutch today, I’m not sure if it’s the original clutch plate but it was worn down to rivets which had scored the driven plate. Happy days!