Clutch adjustment

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jerryg
Posts: 36
Joined: Wed Dec 12, 2012 8:47 am
Location: Bristol

Clutch adjustment

Post by jerryg » Mon Jan 27, 2014 7:33 pm

Hi to all current users. I have just rejoined the club, having purchased a red late mark 1 and would appreciate some advice. The car was restored 25 years ago and during the restoration was fitted with a McCleod clutch. The restorer was the father of the fella I purchased from and having met him, I would guess the car has not been ranted.
But 21,000 miles down the line the clutch has a very high biting point and a slight judder on take up. The evidence suggests the clutch should not be shot but to make it more comfortable to drive I want to lower the bite point. My thoughts are that the only way to do this is to either shorten the master cylinder or slave cylinder push rods. The pedal has only one pivot hole rather than the two I think the brake pedal has, so no options there.
Am I right, has anyone else done this themselves. Thanking any responders in advance.
Jerry.

bigbob
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Joined: Wed Aug 19, 2009 11:31 am

Post by bigbob » Tue Jan 28, 2014 8:30 pm

Isn't the slave cylinder push rod adjustable. Think you can screw the ball end in or out.

jerryg
Posts: 36
Joined: Wed Dec 12, 2012 8:47 am
Location: Bristol

Post by jerryg » Tue Jan 28, 2014 10:52 pm

Hi,
Yes, you're right the slave pushrod is adjustable, but I can't find any real information on how to set it up, even from the original workshop manual. As it stands now, I have adjusted it so that there is 2-3mm clearance between the ball end and the actuating arm, as there was no clearance previously and I'm just repeating the process for setting clearance on a Triumph TR5 clutch which is hydraulic also and therefore similar.
The question is, can I shorten it further without doing any harm and will it give the effect I want ie. to lower the clutch pedal bite point?

ksherlock
Posts: 91
Joined: Thu Jun 30, 2011 9:25 am

clutch adjustment

Post by ksherlock » Thu Jan 30, 2014 11:36 am

You can adjust the pushrod more without doing any harm. There is at least 1/2 " adjustment possible. Just remember the more clearance between the pushrod nut and the clutch lever the lower the biting point for the clutch.

jerryg
Posts: 36
Joined: Wed Dec 12, 2012 8:47 am
Location: Bristol

Clutch adjustment

Post by jerryg » Thu Jan 30, 2014 8:46 pm

With hopefully some drier weather available for test driving this weekend, I shall try that adjustment out. Thank you.

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redbaron
Posts: 111
Joined: Sun Aug 16, 2009 6:18 pm
Location: Essex

Clutch adjustment

Post by redbaron » Thu Jan 30, 2014 10:51 pm

If the clutch slave cyl push rod is shortened all you achive is reducing your clearance.
The piston in the slave cyl will have to take up the amount you have reduced the push rod by and may end up at the total amount of travel for the given master cyl fluid movement.
You say the clutch has 21,000 miles upon it,and as it is a Mcleod, it could well be about replacement time.
Heavy clutches are a probelm and do tend to make drivers slip them more when taking up drive.
You also say the "Bite point " is high,this is also indicative of a worn clutch plate.
The Tiger clutch hydraulics are not adjustable as such,they are a Hydrostatic type and self adjust for wear.
Any change to push rod from factory settings alters the piston travel,more or less in the slave cyl bore.

jerryg
Posts: 36
Joined: Wed Dec 12, 2012 8:47 am
Location: Bristol

Post by jerryg » Fri Jan 31, 2014 12:05 am

The high biting point on the clutch concerned me on purchasing the car, for as you say, it would normally indicate a worn clutch plate. What tempered that for me, was the fact a McCleod had been fitted and I thought with it being heavy duty, it would have surpassed 21,000 miles comfortably but your reasoning suggests not. I think you'll easily see I'm hoping for an alternative to clutch replacement, a job not to be relished.

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redbaron
Posts: 111
Joined: Sun Aug 16, 2009 6:18 pm
Location: Essex

Clutch adjustment

Post by redbaron » Fri Jan 31, 2014 12:39 am

A heavy duty clutch normally refers to the clutch cover,i.e the springs for the clamping force,if it is the original Long Style,with coil springs they will be very heavy,and will become more heavy to push out for clearance as they are compressed.
A heavy duty diaphragm on the other hand give you some form of help as when you push down and move the clutch fork etc, once the diaphragm spring goes "Over centre" it then becomes a little lighter.
A modern diaphragm cover can give as much clamping pressure as the old Long style without the problems of wrecking the hydraulics of the clutch master and slave seals.
The clutch disc may still be an Organic woven facing or a Kevlar/Organic disc,with the organic to the flywheel side.A bit more heavy duty than standard
They still burn and wear when drivers slip the clutch due to the high first gear and high rear axle ratio.
The later Toploader first gear ratio,is more forgiving in this respect,in allowing you to drive away without too much slip of clutch

Tomaselli
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Joined: Fri Sep 30, 2005 2:03 pm
Location: Cheshire, North West England

Re: Clutch adjustment

Post by Tomaselli » Fri Jan 31, 2014 5:12 pm

redbaron wrote:The later Toploader first gear ratio,is more forgiving in this respect,in allowing you to drive away without too much slip of clutch
Redbaron,

I have the later Toploader and find that the first gear ratio doesn't give me slipping clutches but spinning rear wheels. Is that normal :?: :mrgreen:

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redbaron
Posts: 111
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Location: Essex

Re: Clutch adjustment

Post by redbaron » Fri Jan 31, 2014 9:10 pm

Tomaselli wrote:
redbaron wrote:The later Toploader first gear ratio,is more forgiving in this respect,in allowing you to drive away without too much slip of clutch
Redbaron,

I have the later Toploader and find that the first gear ratio doesn't give me slipping clutches but spinning rear wheels. Is that normal :?: :mrgreen:
Tony,
That is perfectly normal for you,easily rectified by fitting a throttle pedal stop to curb your exuberant use of the loud pedal :D

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