My pilot side Matco master cylinders just started seriously leaking this week after 9 yrs. and about 1000 hrs. My cylinders didn't have part numbers on them so I emailed Matco tech support about which rebuild kit is appropriate and got the following in return:
It should be an MCMC-4F. It has a half lug at the bottom making it either the MCMC-4F(R) or MCMC-4F(L). The rebuild kit is the same for both and it is the MCMCRBD4. You will find it on our website at:
http://www.matcomfg.com/MC4REBUILDKIT-idv-3130-46.html
The cylinder is at:
http://www.matcomfg.com/MASTERCYLINDERHalfLugLeft62-idv-3228-5.html
with the drawing at:
http://www.matcomfg.com/InstallationMC4FRLS-idv-2666-21.html
The standard VANS installation uses a bolt from the pedal to the shaft that is not restrained to the pedal. Since the load is offset from the pedal, there is a bending moment when force is applied to the shaft. Since the bolt is not restrained to the pedal, the bending moment is carried in the shaft and causes it to wear against the end gland. Some have changed to an all thread bolt so the bolt can be secured to the pedal with a nut. Some also reinforce the area of the pedal to better support the bending load. A better solution is to use a bolt that goes across both side of the pedal so the cantilever portion attached to the shaft is very rigidly supported for bending.
Please let me know if more is needed.
George R Happ
MATCO mfg
I ordered 2 rebuild kits for the pilot side cylinders. The right side cylinders have hardly ever been used and don't leak.
My installation was made per Vans plans. Another tech suggested that the service life I got out of these cylinders was pretty good and close to what can be expected.
I haven't had brake dragging issues and am only on my second set of brake pads since new. The current pads still haven't gotten down to the wear indicators.
I can see how the long bolts give better pedal response. But, I'm still unclear on how an all thread bolt attached to the pedal provides a more rigid installation to reduce the bending moments.
I'd appreciate any thoughts or pictures you might add.
Mike
It should be an MCMC-4F. It has a half lug at the bottom making it either the MCMC-4F(R) or MCMC-4F(L). The rebuild kit is the same for both and it is the MCMCRBD4. You will find it on our website at:
http://www.matcomfg.com/MC4REBUILDKIT-idv-3130-46.html
The cylinder is at:
http://www.matcomfg.com/MASTERCYLINDERHalfLugLeft62-idv-3228-5.html
with the drawing at:
http://www.matcomfg.com/InstallationMC4FRLS-idv-2666-21.html
The standard VANS installation uses a bolt from the pedal to the shaft that is not restrained to the pedal. Since the load is offset from the pedal, there is a bending moment when force is applied to the shaft. Since the bolt is not restrained to the pedal, the bending moment is carried in the shaft and causes it to wear against the end gland. Some have changed to an all thread bolt so the bolt can be secured to the pedal with a nut. Some also reinforce the area of the pedal to better support the bending load. A better solution is to use a bolt that goes across both side of the pedal so the cantilever portion attached to the shaft is very rigidly supported for bending.
Please let me know if more is needed.
George R Happ
MATCO mfg
I ordered 2 rebuild kits for the pilot side cylinders. The right side cylinders have hardly ever been used and don't leak.
My installation was made per Vans plans. Another tech suggested that the service life I got out of these cylinders was pretty good and close to what can be expected.
I haven't had brake dragging issues and am only on my second set of brake pads since new. The current pads still haven't gotten down to the wear indicators.
I can see how the long bolts give better pedal response. But, I'm still unclear on how an all thread bolt attached to the pedal provides a more rigid installation to reduce the bending moments.
I'd appreciate any thoughts or pictures you might add.
Mike