Triumph Repair: 75 spitfire master cylinder repair, flat blade, correct direction


Question
i  want to know how to get the seal on the primary piston in the master cylinder.it has large ends and trying to slip the seal over either end it keep breaking.does it require a spacial tool or maybe wrong parts. the seal seems a little small. parts house says it is correct part  thanks stan

Answer
Hi Stanley,
While it is difficult sometimes to get the seals on the pistons, you should examine the old seals you took off to see that they look alike and are facing the correct direction. It is necessary to lube the seals to get them on and if you can't force them on by hand you must be sure to use a smooth tool with no sharp edges to try to pry them on like using a tire iron to put a tire on a rim. I have seen some mechanics take a very small flat blade screwdriver and sand it so it was rounded even at the tip so it no longer could be used as a screwdriver but was kept as a seal installer tool. Also a worn piston can end up with sharp edges that will cut a seal as you try to install it, so it is sometimes necessary to debur the edges of the piston too.
Howard