Classic cars forum & vehicle restoration.

[alec.elliot]

Hi there

I am just starting to change the original gearbox on my Morris 8 Series 1 to the four speed unit fitted to the Series E. Before doing this I thought to myself that I would take the gearbox apart and give it a good cleaning/ check for wear, etc.

So far, I have removed the cover and rear housing assembly along with all of the selectors.

My first question is how do you get the input shaft assembly out? I have removed the snap ring in the bell housing on the input shaft bearing and it has come out in the direction of the engine about 1/4" so far but does not seem to want to come out any more.

Does it come out through the bell housing or am I missing something.

All the best

[ukdave2002]

Hi Alec

You need to drop the laygear by removing the layshaft. There is a retaining screw that hold the layshaft in, undo this and then tap the layshaft out, this allows the laygear to drop and provide clearance to dismantle the box.

The layshaft will almost certainly be worn, but can be simply fabricated from some 5/8" steel shafting, the layshaft bearings are off the shelf oilite jobies, all the other bearings are available off the shelf:

Input shaft drive gear, Morris part number ;X15625 :
LJ1NR Imperial Open Snap Ring Type Open Deep Groove Ball Bearing 1x2-1/4x5/8 inch Also known asRLS8NR


Main shaft front, Morris Part number; X15625:
LJ1NR Imperial Open Snap Ring Type Open Deep Groove Ball Bearing 1x2-1/4x5/8 inch Also known asRLS8NR


Main shaft rear, Morris part number; QA11033:
6205, Metal Shielded Deep Groove Ball Bearing 25x52x15mm consider replacing with 62052RS for better oil sealing.

Layshaft bush (x2) Morris part number X15523:
AI1012-20 Oil Filled Bronze Plain Bush 5/8x3/4x1-1/4 inch

Clutch pivot shaft (x2) Morris part number X19325:
AI1012-16 Oil Filled Bronze Plain Bush 5/8x3/4x1 inch

Input shaft spigot bush, Morris part number X15075:
AI0810-16 Oil Filled Bronze Plain Bush 1/2x5/8x1 inch

Reverse gear bush, Morris part number X17342. Originally a single bush, now difficult to source so substitute 2 shorter bushes:
AI1012-16 Oil Filled Bronze Plain Bush 5/8x3/4x1 inch

The speedo worm drive is different, you can either modify the speedo or machine the 3 speed worm to fit the 4 speed box.

Cheers

Dave

[Roger-hatchy]

Hi Alec

I presume it's the four speed your rebuilding.

I have some scans from a period workshop manual of the gearbox and propshaft section,

I can email them to you if you wish.

I have the same gearbox just arrived PM yesterday, I'll be doing a strip and rebuild with new bearings and seals, just got to try and get a top cover and gearstick, or make one.

Roger

[goneps]

Alec,

Possibly you've already found it, but there's an extensive thread on the four-speed conversion here:

http://www.oldclassiccar.co.uk/forum/phpbb/phpBB2/viewtopic.php?t=15230&highlight=

An important aspect you'll need to consider while the gearbox is dismantled is that of speedometer gearing, which is covered in the same thread.

Richard

[alec.elliot]

Hello Gents

Thanks for all of the info. Very useful.

Gearbox apart and well on its way to being back together. Then the fun starts!

All the best.

[ukdave2002]

Hi Alec

Not sure if you have a parts diagram? couple of things to note;

1) there should be a felt seal in the tail of the box, of the 6 box's I have rebuilt it was missing in all but one, it can be made up out of some 1/4" felt.

2) Some box's require shims on the speedo drive gear, as the gear is driven by a friction interface and if there is not enough friction it may slip resulting in an incorrect speedo reading or a flickering needle, worth checking alls working before the laygear is repositioned.

If you use a sealed bearing on the front and rear it will reduce the chance of oil leaks, you can prise the inner facing seals off if worried about bearing over heating but I don't think it's really necessary .

Dave