clutch shudder

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Peter Field
Posts: 3
Joined: Fri Dec 01, 2006 8:18 am

clutch shudder

Post by Peter Field »

Hi can anyone explain why my 1931 SV minor clutch shudders as it is released. Once in motion there are no problems although on 2 occasions I could not get it to disengage before selecting low gear. After reading the forum on clutch adjustment I wonder if I have not got the adjustment done correctly. It has gradually been getting worse over the last few years . Any suggestions would be greatly appreciated Peter Field
martinng
Posts: 147
Joined: Thu Oct 10, 2013 5:31 pm

Re: clutch shudder

Post by martinng »

I had the same problem when I bought my car. I discovered it was a question of clutch adjustment with the levers not disengaging / engaging evenly.
Take off the clutch inspection cover and check / set up the clutch with the 3/32" gap between each lever and the withdrawal race. With luck that will fix it.
All this work requires care so that items are not dropped into the clutch. Attach the 3/32" feeler gauge and adjusting tools to the gear lever with string so that if they are dropped they can be recovered.
On my clutch I also found that the withdrawal pins had worn with an indent on the tip where the adjusters rested on them so it made the measurementof the 10thou clearance impossible. I replaced the adjusters and pins, but this required the removal of of gear box and clutch.
Of course you might find further items of wear (withdrawal race, clutch splines etc), but its worth starting with the simple things first.
viewtopic.php?f=6&t=1521&p=10629&hilit=clutch#p10629
My initiation into clutch adjustment is included in this thread, but perhapss you have seen that aleady.
Incidentally, the keeper springs are there to prevent the withdrawal arms touching the withdrawal race when centifugal force forces them outward towards the race when driving along.
Peter Field
Posts: 3
Joined: Fri Dec 01, 2006 8:18 am

Re: clutch shudder

Post by Peter Field »

Thanks for that. My under standing now is that there two separate adjustments No1 Adjust the levers 3/32 away from the withdrawal race.
No2 With the 3/32 gauge removed check there is 10-15 thou between the levers and the withdrawal pins and adjust by bending the keeper springs.
If I remember correctly I adjusted no 2 with 3/32 gauge still in place. Trust this is the correct procedure I look for a response
peterb
Posts: 73
Joined: Mon Mar 24, 2008 9:30 am

Re: clutch shudder

Post by peterb »

Martin's experience (and that of others) is worth reading.
This Morris Service Sheet suggests the gauge is removed BEFORE measuring the pressure pins.
It is the 1932 version which is fundamentally unchanged from the 1929 sheet.

MORRIS MOTORS LTD.
Service Information No. SV/7

MODEL : MORRIS MINOR S.V.
NO. OF SHEETS 1
SHEET NO.1                                                                                                          
Date of Issue : March 1932
 
Clutch Lubrication and Adjustments
LUBRICATION
A few drops of engine oil should be introduced to the working parts of the clutch, as follows, after removing the clutch inspection cover .
(a) To the clutch thrust race.
(b) To both bearings of the clutch withdrawal fork.
(c) One drop of oil on each of the withdrawal lever bearing pin felt washers. (There are six of these.)
N.B.-The Morris Minor clutch runs dry, and for this reason lubrication of the above details must be sparing. Oil finding its way on to the friction linings will cause clutch slip.

ADJUSTMENTS
(a) Make sure that the clutch pedal has at least 1 in. clearance to the underside of the board.
(b) Adjust the withdrawal levers by means of the adjusting screws so that the toes of the withdrawal levers are each exactly 3/32 in. from the face of the clutch thrust bearing, making quite sure that there is clearance between the toggle lever and the spring keep. (To do this it is necessary to prepare a suitable gauge for insertion between the withdrawal lever toes and toes and the face of the withdrawal race. Any piece of clean metal strip a bare 3/32 in. thick will do).
(c) With the gauge removed there should bc a clearance of from .010 in. to .015 in. between the adjusting screws and the pressure pins on the three withdrawal levers. If this amount of clearance is not present the keeps should be sprung out with a screwdriver until this clearance is obtained.
N.B.-With any type of clutch a certain amount of " settling down " is inevitable in the course of the first few hundred miles' running. In the case of the Morris Minor this means that as the friction surfaces bed down to one another the pressure plate will take up a position nearer to the flywheel cover-plate, and in doing so the clearance provided originally between the pressure pins and the withdrawal lever adjusting screws, and thus between the withdrawal levers and their keeps, will tend to be absorbed.
It is important that there should bc adequate but not excessive clearance between the levers and their keeps as set out in paragraph (c) above. Lack of clearance at this point prevents the pressure plate from being fully released and causes clutch slip.
The clutch cover-plate is not intended to make an airtight joint. One edge is turned up to ensure ventilation of the clutch compartment.
Ian Grace
Site Admin
Posts: 5035
Joined: Sun Nov 19, 2006 12:55 am
Location: USA

Re: clutch shudder

Post by Ian Grace »

A reminder to all that all of the Morris Motors OHC and SV Service Sheets are available and downloadable from the Members' Area of the website.

if you need the username and password to access the Members' Area, just e-mail me. Also, if anyone has any sheets that are NOT listed, please let me know!
Peter Field
Posts: 3
Joined: Fri Dec 01, 2006 8:18 am

Re: clutch shudder

Post by Peter Field »

Yesterday I worked on my morris minors clutch adjustment and found about 40 thou clearance between adjuster and pins with 3/32 gauge removed
I adjusted the 3/32 clearance and then found about 20 thou between pins.
A sharp hit with a hammer and punch on the spring keeps brought that clearance down to 13thou
On a test drive last evening there was very little shudder on releasing the clutch in 1st gear. After several stops and starts there is none.
Thanks all for your input into my cars problem
Ian Grace
Site Admin
Posts: 5035
Joined: Sun Nov 19, 2006 12:55 am
Location: USA

Re: clutch shudder

Post by Ian Grace »

Great news, Peter. Well done!

Ian
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