BT7 3000 - Push rod problem on clutch slave cylinder

[fishyboy]

Hi all, this evening a friend installed a new clutch master cylinder and slave cylinder on my 1961 Austin Healey 3000 BT7. On removing the slave he noticed that a small nut had been put on to the end of the slave cylinder push rod by a previous owner (I have owned that car for 25 years so it was some time ago!).

Why we wondered?

We put on the new slave (without the nut) and bled the system. Low and behold without the nut we where unable to engage gear as there was very little movement on the clutch pedal. Realizing that the the nut had been put there for a reason we removed the push rod from the slave and replaced the nut (1/4 " in width) and hey presto we then got more movement on the pedal and could engae all the gears. the push rod appeared to be a standard size.

Does anybody know whats going on? We assume that the real problem lies inside the gear box. What would be a better solution (without going inside the box)? We guess an ajustable rod might work, but have not been able to find one from one of our usual supplies here in the UK.

Any help welcome.

Phil

 

[Brinkerhoff]

Drive it with the extension on the rod until you need a clutch ( soon). The parts are wearing thin and you are running out of leverage.

 

[RA_Healey]

To much slop due to wear has developed over the years and the nut compensates for the distance throw. As has been said, you will eventually need to pay attention to this.

 

[Keoke]

The replacement Clutch Master clynder should have had an adjustable push rod on it ??

 

[fishyboy]

Hi all,

Thanks for all the advice.

It sounds like the only long term solution will be found when the clutch is replaced.

I have mamanged to find a slighty longer push rod (Dennis Welsh?) which might be a better stop gap than the nut!

My new MC's did not come with adjustable push rods.

We l also noticed that neither the brake or clutch MS wheer shimmed. Does anyone think adding the shims would make much difference.

Many thanks

Phil

 

[steveg]

With fixed-length MC pushrods, the shims are necessary to get the full travel of the piston. See this thread from a month ago:
Clutch Master Cylinder Shim

 

[British_Recovery]

I think the shims actually limit the distance the push rod travels in the master cylinder.

 

[Keoke]

I think the shims actually limit the distance the push rod moves the piston in the master cylinder.?


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