1098/948 clutch swap?

[Hotroddickie]

Im running a 54 Minor as a daily, it is running a mildly tuned 1098 with a ribbed case box.
Clutch started to slip recently so i have just taken the old one out, to find that it is fitted with a 948 clutch (probably why my 60 odd horse 1098 is causing it to slip)

To run a 1098 clutch i know i need to either re-drill the 948 flywheel or find and fit a 1098 flywheel, but do i need to change the back plate, clutch fork and anything else?
Will the starter from the 948 flywheel work with a 1098 flywheel?

Many thanks
Richard

[philthehill]

It will all work better if you change the engine back-plate and flywheel.
The 948cc starter motor will work with the 1098cc back-plate and flywheel.
You may already have the 1098cc clutch release arm (Pt No: 22G166) fitted if you are running a 1098cc gearbox.
The 948cc carbon thrust is secured by a couple of spring clips (Pt No: 7H3048) and the 1098cc carbon thrust is secured by a couple of flat plate clips Pt No: 13H783).

[Hotroddickie]

Great thanks Phil
Looks like i have the 1098 fork.
What is the difference between a 1098 and 948 back plate?

Anyone got a 1098 flywheel and backplate spare? I can pick up within 30 miles of Reading or send a courier to collect.
Doesnt seem to be any on ebay.
Annoying thing is i had them some years ago after putting a 1098 in an A30 but they must have been sold or thrown away!
Richard

[philthehill]

The 1098cc engine back-plate is about twice as thick as the 948cc engine back-plate.
It all helps to enable the 1098cc clutch assy to fit into the bell housing.
Very few 1098cc flywheels appear on 'e' bay these days as just a flywheel - they are mostly attached to an engine.
Here is a 1098cc engine with flywheel and engine back-plate. May be worth a punt and at not a bad price either.

http://www.ebay.co.uk/itm/AUSTIN-A40-MO ... 487c0618fe

[SUE482]

Sorry to intrude but can I ask Phil if he know how thick the back plates are? so that I can see which I have as I have a 1098 engine and an old 803 gearbox at present and am going through the process of fitting a ribbed gearbox with the 803 tail.
Thanks, Ian

[bmcecosse]

The early backplate is steel sheet maybe 1/8" thick - bent over at the edges. The later backplate is actually some kind of cast steel - and is about 5/16" thick - no bending over at the edges... It moves the gearbox back just enough to allow the bigger clutch assembly to clear the bellhousing - even then - the housing has a slot cut out of it just to be sure!!

[philthehill]

Correct at 5/16".