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MG Midget and Sprite Technical - More Marina Crank/Flywheel help needed

I too am in the midst of gathering parts for a 1380. I have

An unmolested Ital (A+) engine. Removed from an Ital in the early 1990s (by myself and father) and never touched.

A Marina engine (via Ebay) of uncertain origins. Its already bored to 1380 and appears in generally good nick but I havent stripped it all yet. It came with flywheel but no clutch. It was intended for a Minor conversion but I'm not sure what transmission....it *may* have been a type 9.

It is the second (the 1380) I am currently struggling with. I've followed the various Marina flywheel/crank threads and am only more confused by what I find on mine!


This is the flywheel that came on the 1380...
http://www.eatworms.org.uk/album/midget1380/clutch.jpg

It has neither the right dowels for a std 1275 Midget clutch (small rusty one top left) or an Ital (enourmous great thing top right). the machined element is 7.5". It has 2 dowels opposite each other and 6 holes right on the edge. Can anyone advise what clutch this may be for ?

Also whats the piece in the middle ? This is a shot of the reverse.
http://www.eatworms.org.uk/album/midget1380/flywheel.jpg

For completeness...a shot of the end of the crank.
http://www.eatworms.org.uk/album/midget1380/Crank.jpg

Thanks






Dean Smith ('73 RWA)

Hey dean,

go back a couple weeks,,probably arcived by now, but Nick durham was working on this excat samething before he died...from what I have read and remember he was vary close to solving the riddle, and most likely even had done so. unfortantly, I think he took the answerer with him when he checked out....id say you might be able to peice his thinking back togather by re-reading and talking to some of the others he was knocking ideas around with at the time...


good luck

prop
Prop

First thoughts, it's been machined to fit a large clutch - possibly Ford Sierra? But i don't know what they look like. Midget flywheel as it's got 2 dowel holes? Lightened at the back?

The insert in the flywheel could be a homebrew spigot bearing?

And the crank looks to be standard Marina. Only one dowel - what is the yellow circle opposite the dowel? Is it overspray or something?

Whats the diameter of the spigot (measure accurately) 78mm ish = Midget, 80mm ish = Marina.

Matt
Tarquin

Dean,

It may be a 1098 flywheel modified to fit the 1275 by redrilling. That would explain the 7.25"/7.5" clutch cover fitment and the 2 dowels, which would suit a 1098 coil spring clutch cover but not a diaphragm spring cover which would have 3 dowels holes. The large clutch you show would appear to not have any dowel holes to suit the placement of the 2 dowels present in the flywheel so is not good. I have seen a large cover like that but can't remember what vehicle, I note the dowel holes in the large cover are offset and not central between the pairs of bolt holes.
David Billington

The flywheel looks to have a standard MMC spigot bearing holder for a type 9 conversion.

Not sure about the flywheel - if you measure the diameter of the spigot it might eliminate a 1098 flywheel modified for whatever. Oh, I see Tarquin has already asked them so I'm on the right track.
Daniel Thirteen-Twelve

Agree with Daniel

the flywheel is proudly wearing the MMC spigot bearing adapter

I did mention this in the other flywheel thread but everybody seemed to be expecing the type 9 to fit into A spigot bearing inside the crankshaft, which can't happen given the input shaft length of the "normal" type 9

I dont know whether the longer shaft version (is that the F100 or V6 box?) would fit the crank if given a modified crank spigot, I haven't seen one.

might save some shortening or other modification if it did...

The flywheel on the right in the picture seems to have two dowels quite near to a pair of opposing screw holes and has suitable drillings and a wide enough contact area

Although it seems likely to be close to the starter ring teeth when fitted it should make fitting a driven plate wide enough to take lots of power I'd guess, Dean what is the diameter of the pressure plate you have there? I'll run it across my parts book so we can hope to find out

Might be Ford plate for a Sierra p'raps

Ooh I do like these conundrums
Bill

From details in the thread entitled "flywheel compatability / modification (1275)" by Phil started 24/08/2008 I think this is a 1098 flywheel modified to fit the 1275 crank as the back (engine side) of the flywheel has no locating recess to fit over the crank. The 1098 flywheel locates on a spigot on the end of the 1098 crank.

See image of 1098 flywheel provided recently to Phil.



David Billington

And front, it has not been redrilled as it came off a 1098.


David Billington

Ahh - Thank you All.

The Spigot on the crank is 79.5mm by micrometer.

Given that the seller was a Minor nut (he had "several"). And they were 1098 (at most) as std - the 1098 flywheel makes perfect sense.

So its a 1098 Flywheel with a MMC Type 9 Spigot Bearer Adaptor. Whats the disadvantage of the 1098 clutch cover - is it simply less capable of handling torque and power than the 1275 ?

My conclusion therefore...

If I'm sticking with my ribcase I should get a 1275 flywheel and get it machined to fit the spigot. (maybe lightened a bit at the same time....)

If I went type 9 this would be a perfect starting point ? Is there a direct replacement clutch cover to mate a type 9 to a 1098 or would the flywheel still need work (new dowels?)

(And yes the Ital Clutch/Flywheel is truly massive in comparison)
Dean Smith ('73 RWA)

In fact....just like this one

http://morrisminorspares.co.uk/shop/popup_image.php?pID=1413
Dean Smith ('73 RWA)

Bill

"I did mention this in the other flywheel thread but everybody seemed to be expecing the type 9 to fit into A spigot bearing inside the crankshaft, which can't happen given the input shaft length of the "normal" type 9"

Well my type 9 does just that. A roller bearing is a push fit into the crank into which the input shaft slides. And my box is from a bog standard Sierra.

Maybe best to take your flywheel to a motor factors and trial fit a Sierra clutch cover. then you can use standard Ford parts which lowers the cost, as the MMOC driven plate has to be specifically made for the project and cost me around £50.

Matt
Tarquin

I've said all along that this type 9 business gets interestinger and interestinger

both of my type 9s have been mounted to the flywheel adapter rather than into the crank end

I'd rather have had a "standard" fitting TBH but MMC said that I would need the flywheeler and so far they've been right*

I know there is a long input version out there, so persoomably thats what you have unless MMC were just guessing luckily, 'cos they never saw my type 9 at their shop

* when I fitted the second type 9 (the one that doesnt have a knackered first gear cluster) I discovered that the MMC spigot was fairy loose-ish in the flywheel as I glued the thing into the flywheel with "Stud'n'bearing fit" from Loctite

Seems OK now, after having the box in and out a couple of times during the CSC fitting excercise


one day someone will be writing up the definitive type9'ers book

but I doubt if we've seen all the combinations yet...
Bill

Well as the box is out at the moment, I'll do the honourable thing and measure it for you.

When I ordered the kit I can't remember them asking if I wanted the crank one or the flywheel one.

I might even put a concentric clutch in while it's out.... I have full instructions from Mr Guy.
Tarquin

I scrapped a late 1098 (10 CG engine) with type 9 that had been (ahem) converted by a notable english company. The spigot bush was a moderately loose fit (by about 3 mm!!!!) and was held in by nothing more than the locktabs from the flywheel bolts being stretched by the use of a BFH. The engine was also the beneficiary of an input of extra iron in the diet via a carb filter bolt in the rear carb throat. The owner wondered why it went so badly.


Still sitting on a shelf in the gerage.


Getting the customer to do the development work is not good practice.
rob multi-sheds thomas

This book (see picture) contains more information on the Type 9 conversion than the current edition, including additional information on the spigot carrier. Also fresh clutch data including co-ax for the type 9.

I think it would be cheaper to get a new spigot carrier for a 1275 flywheel than have a 1275 flywheel machined for the 1098 spigot carrier. Maybe the MMC will be interested in buying back your 1098 with spigot carrier flywheel?

You probably have the smallest and cheapest part of a type 9 conversion so I wouldn't let it influence your short term plans!
Daniel Thirteen-Twelve

Too right Rob!


Matt

a comparison shot that might just be of help

as you see the input shaft is entirely inside the bell housing abd although it might just fit into the crank spigot location, it'ld be only by a short amount

no doubt the MMC bush in the flywheel gives more stability.


Awaiting the measurement comparisons (looks like about a quarter of an inch short of the casting edge to me)


Bill

This thread was discussed between 08/09/2008 and 09/09/2008

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