Timed on #1 or #4 cyl?

[Tas131]

Do you mean the return spring on the actuator arm? While I wouldn't say "you don't need one" (as you should really have one) my car's never had one and I also removed it from my previous Sport and never had problems. The 131 clutch pedal has a strong return spring on it

The spring on the pedal returns the pedal to it's stop, it doesn't help with clutch cable return. The actuator arm spring pulls the cable back and the throwout bearing back from the pressure plate diaphragm fingers, reducing wear on the fingers and increasing throwout bearing life. It also allows easy assessment of clutch freeplay, without freeplay the throwout bearing wears out prematurely, it also pushes the crankshaft forward, causing wear to the crank thrust bearing.

[Thotos]

The spring on the pedal returns the pedal to it's stop

There's no pedal stop on the 131. Not on any of mine anyway    But I agree with everything else you've said Mick which is why I said "you should really have one" 

[keith m 131]

I am goint to fit the spring, I am of the opinion that if the car designer put one there then there is a good reason for it, and Mick has just highlighted why it should be there.

Thanks Guys

keith

[Thotos]

I am of the opinion that if the car designer put one there then there is a good reason for it, and Mick has just highlighted why it should be there.

Both you and Mick are correct, of course  which is why I said "you should really have one". What I was trying to say, was that fitting the missing spring would not solve your problem of slipping clutch.  The reason I don't have a spring is because the hook point on the gearbox is broken and I removed it from my previous Sport because it used to rattle and then preferred the lighter clutch action. Eventually I refitted it in my old Sport and replaced the pedal spring for a much lighter one 

[keith m 131]

I know thats what you were saying Theo, I do listen to you and I'd be a fool if I thought that a spring would fix my problem.
i have been trying a couple of things today, didnt get it finished because I had to remove the pedal box and move the servo so will finish it tomoz and hopefully I will get a good result.

Basically I what I have done is to cut and move the pin that that the cable eye fits to. Before I started the distance from the pin to the back plate of the pedal was 80mm, I have made a "L" shape and reduced the 80mm to 45mm. If need be I can raise the pedal for more travel.

This should give me a lot more pedal travel.  See pic below.

There is also more slack in the cable so the thrust bearing should release fully. Thats the theory anyway.

Regards

Keith

[keith m 131]

Hi All,

Theo, Your advice would be appreciated as this sort of thing sounds right up your street.

Got the pedal box back in and hooked up the clutch cable and because I moved the hook for the cable eye the cable is now too long. I have added spacers etc at the bulkhead and at the bell housing to get the pedal to work but I am having to take every bit of slack out of the cable and that is defeating the object.
So I need a shorter cable. I have a brand new one so if I can get an accurate way to determine what length I need then I can have it shortened but I am not too sure about which way to assertain the correct lentgh. I was thinking about doing the following but whats your opinion.

I was going to hook the cable eye to the pedal and set the pedal to the position I want it at, measure the lenght of the inner cable from the outer cable at the bulkhead to the pedal hook.

Set the actuator arm so that the release/thrust bearing is maybe 3-4mm clear of the pressure plate fingers, set the bulkhead adjustor to the centre of it adjustment travel, slide the cable through the actuator arm and measure the required length of the inner cable from outer cable at the bell housing to the required position on the actuator arm allowing for the locknuts etc to screw on and have the cable shortened to this length.

I havnt allowed for any alteration to the outer cable because I am not sure if that needs to be shortened because if I shorten that then it will make it a bit tighter to route the cable from the bulkhead to the mount in the gearbox bell housing. If I reduce the inner cable then do I need to shorten the outer cable.

Am I correct in what I am thinking or is it not as simple as that?

Regards

Keith

 

[Thotos]

Hello Keith,

Your modification with the 'L' extension would not extend the pedal travel unless the pedal travel was restricted by the length of the cable, which I didn't think was the case. Your modification has extended the inner cable by 45mm so it's now too long. It'll make no difference to the pedal travel. In fact cable length is not important at all, you can have a cable a mile long and it could work fine as what's important is the difference between outer and inner cables. Since the outer cable is fixed at both ends, its length makes no difference at all as long as it's long enough to each between the two fixed points. As long as the outer cable reaches the two fixed points, it can have a lot of 'extra' length and in the RHD 131 it's long enough to go round the front of the engine. The inner cable needs to be longer than the outer cable by the amount of the two fixed points for the outer cable and the fixing points for the inner cable. In the 131 there are two ways to adjust this difference as the length of the outer cable is adjusted at the bulkhead end and the length of the inner cable is adjusted at the clutch actuator end. By extending the inner cable by 45mm you've made the inner cable too long and gone outside the adjustment available by the two adjustment points. So any 131 cable will do you as long as it fits, you don't need to change or modify the cable.

I think what you should do is first determine the amount of extra travel you need to get from the pedal. So what I think you should do is:

   1. Remove your 'L' modification and set the clutch up exactly a you had it before.
   2. Mark or measure the position of the actuator arm and mark the position of the cable adjusting nut. 
   3. Loosen the cable adjusting nut until you get some freeplay at the actuator arm. It should be about an inch but as long as you have some freeplay you should be OK with the release bearing clearing the pressure plate fingers.
   4. Measure the difference in position of the actuator arm to that in 2. above and the measurement is the amount of extra 'travel' you need.
   5. Once you know how much extra you need, you should be able to determine the best way to get the extra travel, either by drilling a new cable hole on the actuator arm, if you don't need much extra, or by modifying the pedal, or both!

If you have to modify the pedal, you need to extend the cable mounting point at the pedal upwards, not nearer the bulkhead. So instead of the 'L' you made, you need to make an 'I'  So you need to extend the pedal upwards keeping the cable mounting point the same distance from the bulkhead. But it's likely that you'll have to drill a new hole on the bulkhead for the cable to go through, it all depends by how much you increase the pedal.

I hope all that makes sense..... 

[keith m 131]

Hi Theo,

Yes what you are saying does make sense. I was of the opinion that if I moced the cable fixing point on the pedal towards the bulk head then the cable would travel more, I was aware that it would lengthen the inner cable thus allow the actuator arm to be pulled backwards by the spring and the release bearing would be free of the pressure plate, just didnt think of how I would adjust the excess cable. Hmmm

Unfortunately drilling the bulk head for the cable to go through higher up is difficult in my set up ( difficult not impossible ) so may have to hold fire on that for the mo.

Tomorrow I will put it back the way it was and check the measurement you recommend and see exactly what extra trave I need to achieve. I will come back to you then.

Thanks again.

keith

[keith m 131]

Theo,

To reset the cable hook point on the pedal back to vertical (80mm) from the bulkhead I need to remove the pedal box and with all the wiring etc in the way it is not an easy task, so before I do that I thought I would ask you this question first.

Whilst I have the box removed do you think that I should set the 80mm distance and then cut and weld the pedal shaft to give me some more travel. I was thinking of cutting through part of the pedal shaft from the rear towards the front and opening the cut up so that the gap is at the rear of the shaft say between 5 or 10 mm obviously I dont want the pedal to be too high and reweld it. Probably between the bottom of the pedal box and the return spring (see pic above). I think that this would be alot easier that drilling a new hole higher up the bulkhead..

Do you think I should do this at this point or put it back as you said, the way it was and measiure what travel is required.

Never realised how many cuts you can get working up behind a dash.

Regards

keith

[Thotos]

As I mentioned in a previous post, my 131 does not have a clutch pedal return stop. If I lift up the pedal, it comes up a long way. Its rest position is determined by the return spring on the pedal. When the spring is in its rest (closed) position, the pedal stops but there's nothing physically stopping it from coming up further.  Assuming your pedal box is the same as mine, you don't need to cut and weld the pedal to increase its height and get more travel. So before you start cutting and welding the pedal, try lifting it up and if it can come up higher, then once you fit the actuator arm return spring and adjust the cable properly, the actuator spring will pull the pedal to the required height. If your pedal has a return stop and you don't mind the pedal being higher than the brake pedal, then maybe you can remove the stop and replace the pedal return spring for a shorter one. I wouldn't cut and weld the pedal at this point as it seems too drastic to me.

If you increase the height of the pedal at the point where the cable connect  by a small amount, say 10-15mm you probably won't need to drill a new bulkhead hole. The cable will be at a slight upwards angle but as the connecting point is 80mm away from the bulkhead you'll only have 5-6 degree upward turn on the cable and I don't think that's enough to chafe the cable.  You might even be able to bend the bulkhead at the cable hole to get a 5-6 degree upward angle for the cable and you'll have no chafing at all. So I still think that what you should do first is to determine how much extra travel you need.

[keith m 131]

Theo, a gentleman as always

Yep thats what I will do regarding slightly raising up the cable eye 10-15mm. i didnt realise that it would be such a small amount. i thought it may have been around 25mm or so which is why I was concerned about drilling a new hole higher up. Yes I should be able to slightly reshape the bulkhead to accommodate the new cable angle.

I dont have a pedal stop. When the cable is disconnected, my pedal return spring pulls the pedal to the floor, so that wont hold the pedal in any position other than on the floor so as you say all the pedal height is controlled by the actuator return spring, never realised that the actuator spring had to do so much work. It is working when the clutch is engaged and when its disengaged. Just aswell that the spring I have is quite robust but not too much to make a big difference to the strength of the pedal..

Keith

[Thotos]

Hello Keith,

Thanks for the complement!

raising up the cable eye 10-15mm. i didnt realise that it would be such a small amount. i thought it may have been around 25mm or so

You may need 25mm or more, you won't know until you make the required measurements. If you're lucky to just need 10-15mm then the modification will be relatively simple but you may need 25mm or even a lot more!

I dont have a pedal stop. When the cable is disconnected, my pedal return spring pulls the pedal to the floor

  Isn't that the wrong way? I thought the pedal return spring pulls the pedal up, not down 

[keith m 131]

My pedal is pulled straight to the floor without the cable connected, see pic.

For a way forward I think it best if I set the clutch back to where it was ie cable eye hook to where it was 80mm from bulkhead and at the original height, I will do what ever adjustment is required to be able to operate the clutch but to do that the release bearing will be in contact with the pressure plate fingers as before ( hence the slipping ) and the bulkhead adjustor is fully turned clockwise.

I will do as you say and mark both the position of the actuator arm and the lock nut, I will then undo the lock nut and allow the return spring to pull the actuator arm backwards to allow the release bearing to clear the fingers by approx 15mm ( is that enough? ) then measure the difference.

When I get to that point, and  if you dont mind I will report my findings to you and then hopefully we will be in a better position to determine exactly what needs to be done to get the clutch working correctly.

I learnt a lesson many years ago, " measure twice cut once" so now I am going to ask twice and do once.

Regards

Keith

[Thotos]

My pedal is pulled straight to the floor without the cable connected, see pic.

No picture unfortunately and I can't remember which way the pedal spring pulls    My 131 is not at home so I can't have a look to remind myself. But I think you're going about it the right way, try and find out how much extra travel you need before doing anything.

[keith m 131]

Theo, see the pic of the pedal that I put up 10 posts back.

Keith