Morris Minor Owners Club

a weight lifter to try and press the pedal before I started dismantling and he couldnt budge it

Are you saying it doesn't move at all? I thought it was just stiff.

You extended the wrong lever - and made matters worse...... Do as many have suggested and extend the correct lever.. It will work.

Does anyone know if,as I have been informed that a standard 1098 clutch will fit?I can't see how given the position of the thread holes in the flywheel if the 1098 clutch is 3/4" larger diameter.While its seperated I would prefer to fit the standard clutch.Yes it was stiff not totally solid but impossible to operate without bracing yourself(no seat in remember)and it engaged by slamming back on.

Let's get back to basics. A 1275 Midget engine has the 6.5" diaphragm clutch that you have as standard, as it does the 6-bolt flywheel. What you have is an absolutely standard 1275 Midget setup, apart from changing the release arm for the mechanical Minor one, which would make no difference to the clutch operation - there are lots of them fitted to Minors.

As said in an earlier posting, you can't 'simply' fit a 1098 clutch to a 1275 engine/flywheel, and why would you want to fit a non-standard clutch that is not rated to take the power of the the 1275 engine. I would think with a standard engine it might be OK, but BMC fitted a diaphragm clutch because they are smaller and lighter to operate for a given torque capacity.

Do you have the engine and gearbox out, or just the gearbox? If they are both out I would reinstall the clutch and the gearbox and try a length of tube on the release arm. It should operate the clutch without undue effort.

Without being connected to the gearbox, does the clutch pedal move really easily throughout its whole movement?

When it was in the car, how did you adjust the pedal to clutch mechanism? What free play did you set it to?

I have just noticed that you were trying to operate the clutch with no seat in the car, which would make it more awkward, so I went into the garage, stood outside the driver's door, and stretched across with my left foot and operated the clutch with minimal effort.

Just found this on this forum.Don't know if its relevant to me?



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Clutch Release Bearing and Fork

Postby tds » Fri Jul 23, 2004 2:51 am
Hi Everybody,
About to attempt a hydraulic clutch conversion with a midget ribbed gearbox to my 948cc convertible (1961). I have a 1098 flywheel and clutch in my parts bin. My question...is the release bearing and fork arm from the midget the same as the Moggie? I have the midget fork arm but no release bearing.

tds
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Postby Kevin » Fri Jul 23, 2004 9:32 am
1st things first what size engine did the MG gearbox come from, also the Midget clutch is nomally a size smaller than the Morris one, in the case of the 1275cc engine I think its 6 1/2" compared to 7 1/4" also the flywheels are different sizes, also I am not sure what else needs changing when fitted to a 948cc engine and which flywheel / clutch combination to use.
Cheers

Kevin
Lovejoy 1968 Smoke Grey Traveller
http://morris-minor-conversions.co.uk
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Not sure on Midget engine

Postby tds » Fri Jul 23, 2004 6:00 pm
Kevin,
thanks for the questions...all good. I picked up the box at british car parts swap meet here in Oregon. The seller had no idea of the Midget/Sprite vehicle but...the box is almost identical in the guts to my Morris smooth case box. So i assumed it is the early spridget. the input shaft to the box matches the Morris 1098 clutch disc just fine. So I think I'm OK there.
Of course from a spridget it has hydraulic clutch and that means the relase fork pokes out the RHS of the box, NOT lhs for my mechanical clutch. hence I plan the upgrade to hydraulic clutch. But the release arm fork is my unknown.
Seems to make sense to go big clutch from 1098 the correct flywheel mated to my 948cc??

tds
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Joined: Wed Jul 14, 2004 9:14 pm

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Postby gcb » Sat Jul 24, 2004 1:36 am
A simple answer for you - the fork arms are different, the midget has more "curve" to contact the flatter midget clutch which is a diphragm type, unlike the moggie one which is spring. With your engine you will have to fit the moggie clutch so you will need a moggie arm. I have one if you are desperate, but not sure about getting it to you!

gcb
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Postby tds » Sat Jul 24, 2004 6:00 pm
Many thanks gcb
I do have Moggie LHD release forks from a smooth case box. But never owned a ribbed box. Do you know if they are the same?
Many thanks for the offer I'am visting family in Brum during Mid-August. i suppose I have to check if the pivot on the front cover of my midget box is Ok for a moggie arm.

Trevor

tds
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Morris vs Midget Clutch arm + the rest

Postby tds » Sun Jul 25, 2004 1:52 am
Well, checked dims on midget arm and front cover with the morris smooth case and their all different. MOWOG made subtle differences which I never spotted. I noted:
1. The curve on the fork arm is more for the morris than midget
2. The pivot point is further out from 1st motion shaft on midget
3. Front cover differences, 3 of 5 studs in different places and pivot is higher from face of box.
So
If my midget box , 22G121, fits only the midget front cover, 22G18, I have to use the midget fork arm,GA15?, and thus release bearing for a hydraulic clutch conversion.

Can anyone tell me if the release bearing postion means I MUST use a midget diaphram clutch on the flywheel? Then what flywheel does the midget clutch fit? My 948 flywheel or 1098 flywheel.
Thanks in advance.
Trevor

Don't know if its relevant to me?

Not really, does more to confuse than anything else. It's more to do with the differences between the 948 and 1098 clutches and gearboxes - the front cover is different on 948 (all smoothcase, Morris, MG etc.) and 1098 (all ribcase, Morris, MG etc.), and not interchangeable without drilling/tapping new holes in the gearbox itself. The 1275 front cover is the same as the 1098 - all ribcase.

Stick with what you have, a 1275 Midget engine, a ribcase gearbox (?Midget, but could be Morris and does not affect the clutch operation) and a standard 1275 clutch and find out why it does not appear to want to work properly.

Does the clutch start to operate 'normally' and get much stiffer, or start out stiff from the beginning? If the former, it might be that the release bearing is fouling the primary shaft (the splined one) as the pedal is pushed down?

Thanks for your patience its appreciated,bodyworks my thing.Its stiff right from the start and stiff is an understatement its totally impossible(and dangerous I just managed to stop before it went through the closed garage door).

Well I now know the reason for the problem.What do I have to do to put it right.Just spent some time messing around with it.I slid the friction plate on the shaft and operated the fork.The fork arm was hitting the gearbox casting as the thrust reached the friction plate!So virtually no actual clutch movement.Please look at the pic of the 1098 fork(left)against the midget fork.The midget one which cant be used with the mechanical mechanism is at least 1/4" further forward(operating end).[frame][/frame]

Make a simple yoke to fit over the Spridget arm - and take the rod for the mech operation. Even if it was just to one side of the arm - I reckon it will be ok........ Just a loose bolt locked in the arm (able to pivot as required) - with a nut securely welded to the head would do the job.

And measuring from the bush to the bottom end the mg ones 1/3" shorter too so less leverage which possibly partly explains why the standard mog mechanism isnt up to it.Can you try and explain a little better the bolt idea,also need something to hook the end of the spring to.I'm a bit thick don't forget.

I don't understand how you have tested the operation by sliding the driven plate down the spline. Can you post a picture?

Saying that there are many examples of what you have working very satisfactorily in Minors does not help, but I really can't see that the solution lies in making up bits and pieces cobbled together to provide an answer.

Can you take a picture of the gearbox back in place, without the gaitor around the release arm and no linkage connected and the release arm pulled back until the carbon thrust touches the clutch? That way we will be able to see if there is enough room behind the lever, in the gearbox slot, for it to work without coming into contact with the casting.

well don't know if i'm looking at the photos wrongly but,with the right hand arm(Midget yes) surely the angle of the arm would mean that once the release bearing was touching the pressure plate there would be more clearance between the lower arm and the box case because the arm is actually going to be pointing forwards,more than the minor arm,and therefore would be less likely to hit the back of the caseing if thats what you mean it is doing. Bit confused .The distance and angle between the pivot point ,top of the arm and the contact point of the release bearing and pressure plate would be exactly the same as on the left hand arm. the only difference would be that the morris arm would be vertually straight whereas the right hand arm would be pointing forwards. The only way it would be different would be if the release bearing or pressure plate were different , making the distance between the top of the arm and pressure plate a lot less than on the minor,is that where the problem lie,perhaps,is the pressure plate thinner in the midget box which would move the lower arm nearer to the box caseing. That has to be it ,its the only way the arm would not be pointing further forwards.

Kennatt yes thats the point.The mog arm is hitting the case before it has been able to move the thrust forward enough to push on the pressure plate.The mg arm won't have the same problem because its bent differently.The problem with the mg arm is that it was designed for hydraulic operation.Instead of the hole at the bottom for the threaded rod it is forked to take a short rod bolted through the fork.The end of the rod went into the midgets slave cylinder.I either have to adapt the mg fork to accept the threaded rod somehow or go hydraulic.To Islip I just slid the friction disc on the shaft and held it down while pulling on the arm.The arm hit the casing before it moved the disc.

aha ,I was thinking you had used the miget arm and that was where the problem was,tis a bit early.and I see what roy was talking about.There must be an easy solution because this conversion is common,and the same problem will have been overcome.wonder if the yoke on the brake rod to master cylinder could be adapted,weld it to the end of the operating rod there must be loads of them knocking about,probably new ones as well.tom roy lists one £8.50

Pic to illustrate[frame][/frame]

crossed post see previous suggestion.

Think I will try opening up the gap in the yoke and welding a large nut in.File the inner edge of the nut to accept the rounded adjuster nut.

Cut off the legs of the mg fork,tigged a 19mm nut in countersunk for the ball of the adjuster nut,tigged a small nut to that for the spring,here goes![frame][/frame]

Make sure the weld is REALLY good - but it should work.

I don't know how to make anything but really good welds.
Clutch fitted.Action is as light as my traveller using the existing holes.