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MG Midget and Sprite Technical - Magneto 948

I've got a Vedette engine to collect next week. It is a 948 A-series with a magneto, a large timing case with the extra gears in it and a cast alloy sump.

Has anyone any experience of these and does anyone know if the 948 sump will fit directly to the 1098? I have some late (10CC) 1098s which I would like to build up with the Vedette parts to go in a 1930s Morris.

r thomas

Rob

AFAIK the 948 sump will fit a 10CG but not a 10CC.

You will need either the 10CC sump, or possibly a 1275 will fit.
Dave O'Neill 2

Nice... make a great end table with a glass top
Prop and the Blackhole Midget

Thanks, Dave.

Do you know where the difference is between the 2 sump shapes? The alloy sump has thick walls so it might be possible to grind it out in places.

The early and late 1098 sumps ARE different so what you said makes sense.

r thomas

The 10CC has bigger main bearings, so the caps are bigger.
Dave O'Neill 2

So, it is just the 2 ends where the rubber/cork sits? Ought to be possible to machine it out a bit. An interesting project, anyway. I'll add some pics when I can.
Ought to help stiffen the bottom end of the engine, if it works!
r thomas

Well, the engine is here. It has been bored +20 with new pistons, has a reground crank, new camshaft and has a simplex chain drive to the cam but the second crank cog goes off to run the magneto which is out by the oil filter. There is a waterpump which is cast bronze and drives off of the camshaft cog via a bolt-on adaptor.

I can sort out most bits on it but wondered if the 'collective' would suggest what I should do about a flywheel and a cylinder head. 948 or 1098?
The other (slightly silly) option is to use the magneto drive to run a supercharger, add a standard Lucas distributor (the hole is still in the block), an electric waterpump and Hall-effect ignition which I still have from a previous engine

It is destined to go into a pre-war car so it needs to look unlike an A-series.
r thomas

That's an interesting engine Rob. Is it to go in your Austin 7?
And, since no-one else dares admit their lack of knowledge, what's a Vedette?

This is what I came up with on Google, but it doesn't seem to tally with the photo you uploaded!

http://tinyurl.com/lusvbq7

There is, also, a reference to a Canadian flying boat, the Vickers Vedette, which might relate to your other interests.

Guy W

Guy

Opening post says 1930s Morris.

I will admit my lack of knowledge, but when I googled it, I came up with boat engines, although your search results look more interesting!
Dave O'Neill 2

Guy,

They were engines marinised for use in boats/yachts.

Goggle Morris Vedette marine engines.

Basically they took the commercially available small Morris petrol engines and added pumps/magnetto's etc to suit marine use.

R.
richard boobier

Ah, so it does. I must read more carefully before posting my question. I would still have had to google Vedette though.

Morris 8 then. I thought Rob might be planning it for his lovely Austin 7. Having owned several 7s, many years ago I found Rob's photos of his 7 reconstruction extremely attractive. Though in a different sort of way to the Vedette ones I found.
Guy W

A bit too hefty for the A7 chassis but I have a '32 Morris Minor (not the later Morris 1000 type Minor) and the original engine is +80 and worn out so it isn't worth saving.
The Vedette series of engines, as Richard says, were any BMC engine with conversion parts to make them useable in small boats such as the Thames Slipper launches. No starter, just a hand crank via gears from an overhead shaft. Either magneto from the rear face of the timing cover or a 25D4 run from a hole in the fwd/aft gearbox assembly. The camshaft sprocket drives a waterpump and another hole runs a mechanical revcounter.
This one was rebuilt but never fitted so it was a good cheap option although I've never owned a small bore engine before, only 1275s and late 1098s. I have a feeling that a 12G295 head will leave it with a very low comp ratio which would suit the supercharging option. I have some of those alloy 1275 heads here that would perhaps be overkill with regards to port size.

r thomas

Rob
Did yours have the OHC engine or the side valve one?
If it is the OHC one I might be interested in the vertical drive gears and head casting etc.
I never mind a spare for my D type
Onno K

Ah, it is a sidevalve one that I'm taking out. Sorry. (Photo enclosed)


Does anyone know if the 948 flywheel will take a 1275 clutch?


You'd think that someone would write a book on this sort of stuff? :O)

r thomas

Rob,

In my experience the bolt pattern of the 948 clutch and the 1275 diaphragm spring clutch is the same but the 948 clutch uses 2 locating dowels and the 1275 3 so you can use one of the 948 dowels and have to have 2 new ones fitted so a bit of machining. I have a 948 flywheel on my 1420 engine with 1098 big mains crank, lightened according to the special tuning data.
David Billington

The bolt pattern isn't the same, but it can be re-drilled.

Three of the holes will line up, but the other three won't. I don't think either of the dowels will match.

The 948 bolts are equally spaced, whereas the 1275s are grouped in three pairs, if that makes sense.

IIRC the friction plate is a slightly different diameter - 6.25" versus 6.5" - but as near as makes no difference.

It's what I used in the A35.
Dave O'Neill 2

Dave,

Thanks for the correction, my memory is obviously going it was a few years ago that I did the machining. Just checked in the shed and I can see a few extra holes in the flywheel face where the clutch cover wasn't covering the face. Maybe it was the 7.5" diaphragm cover that went on the 1098 flywheel with a couple of new dowel pins.
David Billington

If anyone comes across one of these Vedette A-series engines for sale, could they let me know. I'm missing the V-belt assembly that goes through the rear of the timing cover. Doesn't matter if it a 948cc or a 1098cc.

Thanks

r thomas

Thanks, Dave and David. 948 flywheel and 9-spring clutch kit on order.

I've still got to find a few other bits like the massive front pulley, although it might be possible to make one up from scratch.

r thomas

This thread was discussed between 25/10/2014 and 10/11/2014

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