<VV> New Clutch Isnt Working

Frank DuVal corvairduval at cox.net
Sat Nov 24 12:14:57 EST 2007


What Lon means it that for the synchronizers to work properly in a 
transmission, everything has to be like it is driving on the road. The 
fluid has to be at the right level and viscosity. The wheels need to be 
in contact with the pavement. When the tires are in the air, you don't 
have the friction element that slows the gears to mesh properly.

Also, the manual transmission is a very weak fluid coupling, due to the 
viscosity of the gear lube, so even with the transmission in neutral, a 
very slight amount of power is transmitted through to the output shaft. 
The tires resting on the ground will never turn with this slight power, 
but up in the air they can.

Frank DuVal

Steve Brennan wrote:

>Lon, 
>Do I understand you to mean I should put the car on the ground and do the
>same test?  I attempted to do the "burn in" with the car on stands, but with
>the emergency brake on.  Is this not sufficient?  In any event, how many
>"burn ins" is a reasonable amount?  I just did about 4, letting things cool
>off for a minute or so between attempts.
>  
>


> Upon doing the installation, I did notice that
>the bushing fit on the shaft nose rather tightly, so I worked it off and on
>several times and "pressure-oiled" it up well, per the books.  That said, I
>did not anticipate this issue, so did not use an emory cloth or take any
>similar action, which I now wish I had done.
>  
>

It is OK for there to be no radial movement between the bushing and 
shaft. There should be rotational and axial movement!

>In any event, is there a way to confirm that my problem is caused by a tight
>bushing before I pull the drive train back out?  
>  
>
No. You cannot tell the difference between tight pilot bushing or tight 
clutch. Operationally they are the same.

>Steve - NEVER NEVER NEVER assume that you have an engagement problem by 
>testing it with the car on blocks. It only takes the slightest amount of 
>tightness to make you think that the clutch will not disengage! IT IS 
>NOT A REASONABLE TEST!
>
>
>
>Steve Brennan wrote:
>
>  
>
>>I just installed a new Kevlar clutch in my 1962 Spyder Coupe.  All seemed
>>    
>>
>to
>  
>
>>go well with the installation of the clutch and putting the drivetrain back
>>in the car, at least until I started the engine and tried  putting the car
>>in gear (while the car was still on stands).  While I can get it into 1st,
>>2nd and 3rd gear, it does not feel smooth, as it was before installing the
>>new clutch.  Worse yet, if I try to put it into 4th gear or reverse, it
>>    
>>
>just
>  
>
>>grinds, as if I was not stepping on the clutch at all. 
>>
>  
>
This is a real clue right here. If it engages 1st and 2nd but grinds 
into 4th, this is opposite of most clutch problems. 4th is the easiest 
gear to engage. Get the car on the ground to get the friction back in 
the system.

You are stepping on the brake and have the wheels not turning when 
engaging reverse? Any wheel movement here will grind.

Frank DuVal


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