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clutch stiffness problem
darren(SA) - 24/9/02 at 02:17 PM

Hi guys,

I've got a 1600 crossflow on a cortina 4 speed gearbox in my locost.

the problem is that the clutch is far too hard to press!

We took the clutch + flywheel off and had it tested but they are both in perfect nick. This leeds us to either the clutch cable or the pedal.

The pedal is the same spec as the original Birkin's, while cluth cable is shorter.However, when disconecting the cable, it moves freely through the bend by hand. It is my understanding that the cortina has a hydrolic clutch, so could this be the problem?

Feedback would be appreciated

thanks
darren


JohnFol - 24/9/02 at 03:17 PM

(I presume you mean pressure plate and not flywheel)
I'd do the following.

1) Disconnect the cable from the release leaver. Can you pull the leaver? If not, then it sounds like the fitting of the gearbox. (ie release bearing not free to move, or splines not central in clitch plate)

2) Re-connect cable to lever and disconnect from the back of the brake pedal. Does leaver move when pulling on the cable? It should move. (remember you do not have the leverage of the pedal so it will be hard, but not impossible)

3) Check the pedal travels without the cable to prove it is not being fouled or blocked.

4) Re-attach cable to pedal. You know the cable works and the pedal moves. If it now stops moving then the bend is causing the problem.

5) Drink lots of Guinness and use a foot pump to build up that leg muscle.


Highcost builder - 24/9/02 at 04:48 PM

the clutch cable route is fine you dont need to go hydraulic ive fitted a cable to my x flow and 4 speed box and then to a x flow and 5 speed t9 and they both worked fine. nice fault let us know what you find.


theconrodkid - 24/9/02 at 05:27 PM

What cortina did it come out of,mk 1+2 were hydraulic,mk 3 on were cablesounds like you are trying to pull when when the lever wants to be pushed ,if you get my drift?


Highcost builder - 24/9/02 at 08:09 PM

good point up there


johnston - 24/9/02 at 09:22 PM

also is it qh clutch as they can be as heavy as f**k especially if it was on the engine and has sat around for a while


davef - 25/9/02 at 10:36 AM

hi darren, i also am using 1600xflow & 4 speed c type gearbox from a mk4 cortina. i experienced the same problem as you, so i started to experiment. at the start the distance from the the pivot point to the cable attachment hole was +- 100mm and was far to stiff so i drilled another hole for the cable closer to the pivot hole, a definate improvment. after further drilling of holes ever closer to the pivot point it ended with the cable mountng hole +- 50mm from the pivot. the result was a nice easy action with very little effort required. it,s all down to that old greek guy who said give me a lever big enough and i will move the world. cheers davef. from durban SA.


darren(SA) - 26/9/02 at 05:58 PM

Sorry It's taken me this long to get back to you guys, the builders next door chopped my telephone line

JohnFol: I took everything, the flywheel, pressure plate & clutch plate-> they said they were OK.The lever is too hard to move by hand,we've checked the bearing,checked the splines all seems OK.

Highcost builder: Nice fault? theres no such thing! hehee just kidding.Not giong hydrolic saves me some time& $$$

theconrodkid: It was a MK4, same as davef's

DaveF: It's good to know someone had the same problem as me! I must measure the distance to pivot point and compare it to yours, I'll measure it tomorrow and perhaps even drill a couple of holes. Won't moving the the hole closer to the pivot point shorten the travel too much?

Thanks for the great response, its much appreciated.

darren


davef - 27/9/02 at 07:58 AM

hi darren, no the travel will be fine, it actually makes very little difference. but the change in pedal pressure is dramatic.
cheers davf.


paulf - 27/9/02 at 05:53 PM

I have also found my clutch pedal to be heavy and considered altering the pedal ratio. How much cable travel is needed at the release arm attachment? i presently have 40mm total travel, but think i only need about 20mm to operate the clutch. Can anyone confirm this?.
Paul.

quote:
hi darren, no the travel will be fine, it actually makes very little difference. but the change in pedal pressure is dramatic.
cheers davf.


bran - 27/9/02 at 09:32 PM

Hi Darren,
If my memory serves me correctly mk 1 and 2 were hydaulic clutch and mk 3 on were cable clutch, the operating difference was the hydaulic pushed and the cable pulled the clutch lever. This means the clutch operating levers are not pivoted at the same point, the hydaulic is between the cylinder and the clutch, the cable type is on the other side of the gearbox, don't know if this helps,
regards Colin


bran - 27/9/02 at 09:41 PM

Hi Paul, regarding cable travel, 40mm travel does seem about right, but I will check the drawing archives on Monday (if they go back that far) and get back to you.
regards Colin


darren(SA) - 29/9/02 at 10:48 PM

Hi DaveF,

I measured the distance from the pivot point to the cable, only to find that it is 50mm Do you think it could be the distance from the pivot point to the bottom of the pedal that is too short(+-210mm)?

thanks
darren


davef - 30/9/02 at 06:13 AM

hi darren, i will measure it all up tonite, but from memory i am sure mine is longer than 210mm. and i know that the pivot point is elevated above the chassis top rail, check you tommorow. davef


darren(SA) - 30/9/02 at 07:56 PM

Thanks Dave!

I'll try measure my pedal again, 210mm was what I remembered.If worst comes to worst, I'm going to take photo's of the whole thing from g/box to pedal and let you guys have a look!

cheers
darren


davef - 1/10/02 at 06:16 AM

hi darren, measured the pedal last night,
the distance from the pivot point down to the center of the pedal is 280mm the distance from the floor to the center of the pedal is 185mm, the distance from the top side of the top rails to the pivot is 130mm the 50mm from pivot to cable hole kicks off at 40degrees towards the front of the car, that 40 degrees is when the pedal is hanging perpendicular to horizontal. hope this helps davef.


darren(SA) - 1/10/02 at 08:07 PM

I also hope that helps!I'll compare the specs and let you know.

thanks alot,

darren


darren(SA) - 12/10/02 at 09:11 AM

Davef!

I measured my pedal up only to find the following differences: My pedal arm is 130mm shorter than yours, which is exactly the distance from your top rails to the pivot point! This must be my problem, 130mm is a lot of leverage! My pivot point is is line with the top rail where it should be 130mm above!

Mine is however very much the same as my friend origin birkin, only his has a escort 5 speed box. So it looks like the setup for the cortina's 4 speed and the escort's 5 speed requires a different leverage system.

Hope this does solve my problem

thanks 4 the help,

darren