Paramount brake cylinder rebuild

[Shadrach]

Is anyone else had problems replacing the seals on paramount brake cylinders with the LASAR o-ring kit? The O-ring for the plunger shaft appears to be  larger than the original. It does not fit in the machined cutout on the cap. It does not squeeze into place, So the circlip that holds the whole thing together cannot be installed. The cotter pins are also oversize and must be deformed the trim to ensure they do not make contact with a cylinder wall.  Will post picture soon.

[PT20J]

I recently rebuilt my Cleveland master cylinders. I ordered the O-rings from Spruce using Parker documentation, but when I was looking at the M20J IPC, I noted that it included an exploded view of the cylinders including Paramount and appears to show the internal O-ring part numbers. You might check your IPC and see if it has similar info and cross check the part numbers with the LASAR kit.

EDIT: Here’s the M20J IPC pages if it helps

[47U]

16 hours ago, Shadrach said:

Is anyone else had problems replacing the seals on paramount brake cylinders with the LASAR o-ring kit?

Building on Skip’s post… some of the older mx manuals had exploded views of hydraulic components.  The below is applicable to ‘67 F serial numbers 660003, 660004, and 670001 - 670539.

 

[Shadrach]

Thanks gents. I think it’s just a case of revisions to the original PN, as well as the fact the Lasar lists the same PN for both cotter keys wherein the manual they are different as are the PNs. Fortunately the internal cotter key need not be removed for o-ring replacement and therefore need not be disturbed.  I won’t be using theirs.

As for the O-rings. I think it’s just a really tight fit That will require a circlip installation tool to sufficiently compress the assembly. 
thanks again for your thoughts.

 

 

 

[Kelpro999]

Definitely don’t forget the external cotter pin near the clevis. It prevents over stroking and damaging the shaft o-ring. I found out once 

[Shadrach]

10 hours ago, Kelpro999 said:

Definitely don’t forget the external cotter pin near the clevis. It prevents over stroking and damaging the shaft o-ring. I found out once 

Fortunately, those were the only pins that were removed so they would be harder but not impossible to miss.