Thread: Dual 7" Servo
View Single Post
  #26  
Old 9th November 2011, 08:51
Mike Mike is offline
Senior Member
Enthusiast
 
Join Date: Jan 2007
Posts: 932
Mike is on a distinguished road
Default

Quote:
Originally Posted by GreatOldOne View Post
I assume this is the adaptor plate between the servo and the master cylinder? Looks as if you've cut a rebate for the sealing o-ring into it...
For anyone interested:

I am not sure whether the Dual servo requires a seal to be maintained between the servo and the master cylinder. The Metro unit definitely does, but the Dual probably does not.
I have made this back plate as a trial for testing, and will deliberately leave a leak to confirm whether the seal is necessary or not.



This photo shows the exposed chamber of the Metro, whereas the Dual clearly has a sealed chamber.


Jason, and anyone interested
I know you are attending metal work classes, so you could make a back plate.
Dimensions are:
Plate - I chose 6mm mild steel: 5mm would be OK
Outer diameter: 108mm nominal
Inner diameter : 40mm for my Sierra master cylinder: generally to suit your own master cylinder
Recess diameter : - if required +5mm on diameter
Recess depth : 1.5mm when using 6mm plate
A cut out will be required for the vacuum elbow : drill 30mm diameter offset centre from perimeter approximately 5mm

Holes for servo fixings :2 x 10mm dia. on 87mm PCD
Studs for master cylinder : M8 x 20mm projection for my Sierra master cylinder, but generally to suit your master cylinder
Offset of servo holes to master cylinder studs : for my Sierra master cylinder approximately 75 degrees, generally to suit your own master cylinder

You may require a spacer between the servo output push-rod and the master cylinder : my Sierra one will require approximately +6mm
Reply With Quote