33 replies to this topic

[baldric]

please can some one give me the measurments of the master cylander to pedal push rod centre of the drillings to end of the rod I have a nasty suspicion I not getting enough throw I think some one has used a 1100 push rod and I think they are slightly shorter than the mini ones by about a 1/4" inch the pedal box has been rebuilt and I want to get these master cylander rods correct before fitting back in the vehicle and also the length of the slave cylander rod reason for these measurments impossible to get into gear without a grind of gears system has been bled a couple of times
thanks

[Racing Gold]

Personally I would get a new cylinder. If you are taking it out and it has obviously been out for rebuild before then it is a waste of your timefor the cost.. I only use AP parts including for slave, not a job you want to keep repeating. Not only that, you will get a true feel to your clutch and eliminate that as a cause of your problems

[Ethel]

As the master pushrod is part of the cylinder you could cross reference some part numbers to see if the Mini & 1100's are the same. I guess it's a single line cylinder for a pre '76 car?

The slave rod shouldn't be critical, as the slave also takes up clutch wear. set the return stop clearance and see how much rod that leaves to go inside the slave.

[baldric]

thanks gents ok the full story is I haven't been around minies since the sixties mostly Cambridge a40 a40 farinas a30 and flat populars/ford and 1100 at my age I have forgotten a lot about vehicles

my daughter has bought a going mini clubman which has been some what restored to the stage of being a waste of time ,,, to my thinking someone has thrown a box of bits at it not caring what went where total mess ,,, the machine is going to be fully restored in the near future to a reasonable bit of kit , the spit has been built also a 36inch folder built and a 16 inch through folder half built the point is I don't buy what I can fabricate being retired I like to be careful with the cash,

all I want at the moment is to get the heap going so she can have a bit of fun with it ,

some article who is unknown to myself has made up a slave cylinder pushrod to clutch lever bit of bolt welded to original pushrod which is in total length about 4" 1/4" long which I believe the original is 1" inch shorter ,,, as I have a better than average workshop and reasonable amount gear to support the machines I make most parts that are required , fitter turner comes to mind ,

the vehicle was going has some rust but roadworthy I just require some measurements before I switch the lathe on and mill running ,,, this being the mini site , this would be the first place I would try there has to be a few experts here

thanks very muchly for replying to my request vehicle is a clubman as you say single line and something in that line is not giving me enough throw ,

thanks gents I will awate until I accrue a few more answers if possible
baldric

[Ethel]

I assume it's Pre Verto if it's a Clubby (suppose I already had, by jibbering on about return stops), I'll try to measure mine tomorrow. Like I said it shouldn't be particularly critical, lengthening it is a common botch to try and work round wear elsewhere in the release mechanism.

[baldric]

thanks ethel I agree with the critical length originally there was no return spring one has been fitted by me and a new clutch levere . I thought I had cracked it the ball on the end of the clutch lever had broken off fitted a new one ,,, I have a niggling thought it might be inside the bell hope not the pedal box has been rebuilt there was more ware in that what I care to mention broken welds and elongated holes with all the slack in the pedal box cluster that could given me 1/2" at the end of the clutch lever clevis pin end I am working my way through the system methodically to eliminate all known factors knowing this vehicle there is too many rogue parts in it done by bodgers this is why I haft to have a datum point to start from ,,, in this vehicle I don't know what is gospel

I thank you very much going to measure that is really appreciated
baldric in western australia

[tiger99]

What I can tell you is that the operating stroke of the slave cylinder, from pedal up to fully down, should be 0.55 inch.

 

As for the push rod length, I would think that Minis and 1100s must be the same, as the clutch is the same. But there have been a number of cases on this forum where people needed to lengthen the push rod, and in some cases, after lots of new parts, the cause was never found. I assume it to be due to a combination of wear and badly manufactured new parts. Prime suspect would be the thrust bearing, if too thin the lever would be further away from the slave cylinder.

[baldric]

tiger 99 thrust baring that's a good thought ,,, it had entered my mind when I saw the lashup of the slave cylinder push rod my first thoughts and have done taken all the slack out of the pedal box and all associated levers and believe me there was certainly was some slack especially the pedal bolt it had worn the holes oval very close to a 1/16 oval that was on the brake side where the large spot welded washer is on the pedal box cluster that washer is only there to support (((the washer has been removed and a new one turned up and spoted on)))) the pedal cluster bolt the reason the hole wore to an oval , and I assume that some one some time had replaced the 4 bronz bushes and did not ream the bushes to a reasonable clearance fit on the pedal cluster bolt , in other words the brake pedal bushes had seized on to the pedal cluster bolt the whole bolt was revolving with the pedal when the brake was operated where as the clutch pedal was free in movement on the bolt , the hole in the side of the pedal box where quite worn from the pedal cluster bolt but not quite so oval but quite enlarged and also the cluster bolt had worn down where it had been partly revolving that is on the left hand side on the thin wall of the box I have also turned up a new washer and spotted it on to hold the thru bolt in position , the new cluster bolt which has been turned up to slightly larger than original the pedal bushes have been reamed to fit the new cluster bolt , the only other modification I have done to the thru bolt is drilled down the centre of the bolt and half crossed drilled the bolt in 2 positions to line up with the centre of the bronz pedal bushes and fitted a grease nipple to the left hand side of the thru bolt that will stop the silly thing seizing again , I wont say its a bad engineering design they did-not expect these vehicles to last this long also the hex head of the thru bolt will be locked in position with a tab the pedal cluster is now as good as new bolt solid in position no side movement of pedal and the pedal spring fully returning the pedal ,,, my apologies for rambling on not only am I getting help I hoping these scribes are helping others , there is a lot of joints in the pedal box and clevis pins , if not addressed properely will have final effect on the clutch lever throw , most people might buy a new box . i am afraid i don't i like to rebuild and get over the problem why the clutch system has given me a problem --- tiger 99 --- your suggestion has been well received about the thrust baring its a good thought and i will tackle that part and the pin in the tare down and refurbish i also suspect the clutch pin lever hole has worn as well thanks for your input appreciated<br />baldric

[baldric]

last  evening I decided to do a lot of googling  ,  it was 2.30 in the morning ,,, with the information that I have gathered . I have come to the conclusion that the problem of the clutch  release  is a big problem  to a lot of people who own minies  why this should be so is open to conjecture  so much so  . I have decided to  delve into the master cylinder and slave cylinder  , which are working reasonably well at the moment  holding pressure  with no retraction of the clutch lever when the pedal is held down , I had not realised that  there is so many threads about this problem on this site ,,, with people who had tried to accrue help , it seems to me its not a problem that is going to go away .  please bare with me  with  my ramblings  as I try to find the cause  , and scribe my findings on this thread ,

Charles     aka   baldric

[baldric]

 MR-56-35_0714_zps23bf8f07.jpg   69.2K   12 downloads                                                              
 
the left hand master cylinder push rod is for a 1100 and the right hand side push rod  is for a mini  I am not sure of the reason for this  ( please don't take it as gospel )  , I did not take the image so cant vouch for the picture   if true  its something to watch for  when buying  second-hand  parts  

Edited by baldric, 22 October 2013 - 02:30 PM.

[baldric]

my apologies for double  image  (first time posting a image)

yesterday  i removed the clutch master cylinder  and slave  and the clutch  diaphragm  plate  the plate was a spare one  purley to see/ measure the set of the diaphragm  spring

[Dan]

  All that should really affect though is the position of the pedal, providing the pedal doesn't strike anything like the inside of the crossmember before the cylinder bottoms out then you are still getting full stroke.

[baldric]

hallo dan

baldric returning  pleased that some one is interested , have done some bench tests to day, the pedal shouldn't strike the inside of the crossmember . I  am getting full stroke on the bench  it all points to one thing at the moment  the stroke of the cylander  is perfectly adaquit  otherwise the vehicle would not been built  like that  ,, the thing is the setup is very close to go no go  , and ware is a big factor ,  I will explain later  with images   , which haft to be taken of the camera   ,   thanks for your interest   i  haft to get to the bottom  of this  its doing my head in at the moment  , mind you  there light at the bottom of the tunnel , if i am on the right track

baldric

[tiger99]

If your master cylinder push rod is too short, the circlip in the master cylinder will be taking a pounding when you release the pedal, which is not good. Don't know if you will get full slave travel or not, before the pedal hits something.

 

Ordinarily the pedal upward travel is limited by a stop in the pedal box assembly, and the pedal should return to sit against that stop, at which point the master cylinder push rod should be slack, but only just.

 

The bulkhead and pedal box are of course different in the 1100, and I have no detailed knowledge of these, never having owned one. But someone missed a trick, they should have dimensioned the metalwork so that the push rod was the same length as the Mini, and avoided the cost of sourcing two different parts where one would suffice. That sort of thing is one of the many reasons that Ford are doing well, while BMC/BL/Rover are gone.

 

(If the rod was too long, the piston would not uncover the reservoir port, and would cause serious but different problems.)

 

But if you can get 0.55" travel at the slave cylinder, in the car, none of that matters for now except that the pedal height may be wrong.

 

I must admit that I am very interested in the final outcome, as we see lots of similar clutch problems nowadays. I think they were fairly rare (except for leaking hydraulics) 30 or more years ago, so something has changed, maybe just an accumulation of wear in many places, although the dimensional accuracy of certain spare parts has been questioned previously.

[baldric]

hallo tiger

what you say is very true the pedal stop and final fitting is unknown to me as yet ( the silly pedal cluster )  not fitted as yet , nor do I know the overall outcome  granted the return spring will make the piston return to the circlip  there for the stop will haft to be fitted ,,, now the free master cylinder  stroke  movement  on the bench connected to the pedal cluster  which  is  1" 1/4" I wont deal in thows  plain English measurments  so every one can understand ,,, I will try to add images  explaning what is going on  ,,, and this does not mean that I am going to solve the problem , just an ordinary  cove who would like to know why this is happening

Edited by baldric, 19 October 2013 - 01:49 PM.