I put a new mastercylinder on front brakes. The plunger in the old and new cylinder stays engaged and brake fluid runs out air can. What am I doing wrong? Thanks
Not sure what you mean by "plunger in the old and new cylinder stays engaged". Like always best to include a S/N so someone can get a better idea of the system you have. Did not try to look on SIS but there could be a dozen different versions of a 920.
sorry Its a 62K serial# the plunger is the piston inside the mastercylinder It keeps going to far and hangs up and allows brake fluid into air can. Thanks
You need to bleed the system and have the brakes adjusted properly before you apply air to the can. pressure bleeder or reverse bleeding probably best. The master cylinders maybe are supposed to stop before they travel too far, but if the brake system was working correctly the fluid pressure would prevent overtravel. :my2c
Thankyou I will check rest of system.
62K narrows it down a bit but depending on the system I look at there are changes within the 62K. In brakes it looks like there are three versions 62K0001-02778, 62K02779-09972 and 62K09973-UP. As you mentioned yours has the Wagner-Lockheed masters I would think it was one of the first two. Seems strange that the piston in the master is going too far and letting the fluid leak out the back of the cylinder into the air chamber. Did the brake work good before this problem? I understand that they would be overstroking if there was a fluid leak or when put on new before being bled, but find it hard to imagine that they would be designed in a way that they would stroke so far that the piston would go past the fluid port in the master. Makes me wonder if there are some incorrect parts involved in the assembly. Is it possible someone installed an air chamber with the wrong push rod? Or the wrong piston in the master?