gearbox seperation

[dellerie]

i'm currently trying to seperate the rear of the gearbox from the bellhousing piece. i want the tailshaft from this 803 box, for mating to another gearbox with better gearing.

i've undone the 9 bolts around the tailshaft and remove the front cover inside the bellhousing but i cannot seperate them. i have tried everyway of doing it but am hitting a brick wall. i've resorted to cutting through the 3 shafts that i can see inbetween, but that still won't work. i have tried clamping the motion shaft in the vice and undoing the nut where the bearings are. all that happen's is that it turns in the vice.

before i get the angle grinder out and cut the box up, is there something else to try?

i need the tailshaft for another box, so the rest of the box is scrap as far as i'm concearned........ but the internals look in fine order and someone may need them in the future........

can any advise?

[RobThomas]

Speedo angle drive removed?

[dellerie]

Speedo angle drive removed?

thats something i've not tried!

[dellerie]

speedo drive was removed. i still cannot seperate the 2 halves. i shall get some pics..........

[dellerie]

ok then, i can't go any further.






any idea's on how i seperate this box.

[bmcecosse]

I can't make out from that picture - are the selector fork clamping screws removed - or sheared off?

[dellerie]

I can't make out from that picture - are the selector fork clamping screws removed - or sheared off?

i removed them.

[bmcecosse]

And so - can the selector rods not slide out now? Have you removed the interlocking plungers ??

[dellerie]

would that be through the bell housing end?

[bmcecosse]

No - unscrew plugs in the side of the casing - it's many years since I did one of these........ but it's all in the Manual I'm sure.

[dellerie]

you were right BMC, i slid out the rods and the gearbox came apart. my aim is this....



this is for my A30. i want to use a 1098/1275 gearbox, but with the Series 2 minor tailshaft. it keeps the car looking standard, but allows me to fit a larger engine without killing the old 803 box.

[liammonty]

beware! The series 2 Minor tailpiece is longer than the A30 one, as I discovered when I was converting a 948 'box to fit my series 2. I'd inadvertantly used a donor A30 box tailpiece, not realising they are different lengths... I wasn't happy when I discovered the propshaft didn't reach the gearbox!!!

[dellerie]

beware! The series 2 Minor tailpiece is longer than the A30 one, as I discovered when I was converting a 948 'box to fit my series 2. I'd inadvertantly used a donor A30 box tailpiece, not realising they are different lengths... I wasn't happy when I discovered the propshaft didn't reach the gearbox!!!

no, i definatly want the MM tailshaft and then i can use an A35 prop. i know it's longer.

[liammonty]

Just trying to save you some time had you not known about it

[bmcecosse]

That tail piece will fit the box you show in the picture (a smooth case 948 box) but it won't fit a ribbed case 1098/1275 box without some considerable machining (or bodging)!

[dellerie]

That tail piece will fit the box you show in the picture (a smooth case 948 box) but it won't fit a ribbed case 1098/1275 box without some considerable machining (or bodging)!

i understand that. but there is apparently a man on the south coast that can fit 1098/1275 internals into that smooth box, then i use the MM tailshaft. it would make a stronger box, but look as though it's standard.

i believe you can't use the ribbed box due to the reverse gear?

[bmcecosse]

No - it's to do with the fit of the tailshaft I believe - although a lad who used to be on here a lot (but moved on a Triumph Herald !!) did the job using hand grinder/file etc - so it can be done. If you have the 1098 box - try offering up the tailshaft and see what stops it going on!

[dellerie]

at present, i don't have a ribbed box to check, but do remember reading on a forum that the spline could be too long for the MM tailshaft.

on 2nd thoughts, would the standard 948 box be too weak for the 1275?

[liammonty]

I think the conversion offered by the gearbox specialist uses the ribbed 1098 box and the 803 tailpiece- it doesn't involve changing the internals. There is machining required when doing this (I can't remember of what, and when I did mine none was required as I mated a smooth 948 box to the 803 tailpiece). You'd be best searching for posts by 'Callyspoy' who BMCecosse referred to- he's the one that did all these conversions to his SII.

It would be fruitless to use the smooth case if you're after extra strength from the box though, as the whole point of the addition of the ribs to the later box was to strengthen it. I think the internals (with the exception of the synchromesh) are otherwise very similar strengthwise, having had both types of box in bits.

I'm sure the 948 box will be OK with the 1275 driven sensibly, but it won't be as strong as a later ribbed one. Depends how hard you want to drive it!

[win]

Hi
I did the same thing to my series 11, that is fitted a ribbed box and still retained the long gear stick.
Remove the extentions from both boxes, compaire the posistion, and shape, of the gear selectors.
This will show you how much work is involved.

Regards Win