Master Cylinder Brake

[Guest smac1221]

I received my new Master Cylinder today. Are there any special preperation that need to be done before installation? I assume the rubbers are pre-lubed inside, but do I need to pre-fill and do some bleeding to the cylinder itself or just bolt it on and bleed lines as usual?

Thanks,

smac1221

[grey beard]

Yup, you gotta' bench bleed it first - very easy to do. Just hold it in your vise and fill it with the fluid you will be using, then get your largest screw driver and put a rag underneath the cylinder. Stroke the piston with your screwdriver as a push rod - go the whole way in, then put your thumb over the outlet for the return stroke. Continue to do this three or four times, until only fluid comes out and no trapped air, then wipe it off and install it. That's all there is to it.

Some new master cylinders come with a plastic fitting that screws into the outlet hole with a little plastic hose that you put into the brake fluid so all the air can escape. You just pump the piston with your screwdriver until no more bubbles show up in the fluid - not as messy, but either way works just fine.

I recommend to all Pilothouse captains that they consider using a remote master cylinder reservoir - mounts on the fire wall and costs about $30 bukkz. Then when you open the hood, you can LOOK at the fluid level, and you'll never get dirt in your new master cylinder trying to service it in that lousy position behind the steering box - especially if you're a little (gulp) chubby, like me - hard to reach - impossible to see. Got mine from Pegasus.com on the net. JMHO Lots of luck.

PS Actually, I'm a lot of chubby - not just a little! Go figure . . . . . .

[Guest smac1221]

And if you did not bench bleed it, would you continue to get air in the lines?

I honed my old Master Cylinder, replaced the insides with a new kit, changed upper an lower rear cylinders on the brakes, cleaned my front duel cylinders, replace one rear line and have bleed and bleed and bleed the line with about 1 1/2 quarts of brake fluid, only to keep getting bubbles.

I thought that if I replaced the Master Cylinder that might fix the problem.

Before I install the new one, I think I'll bench bleed the old one and try some more bleeding or another quart of brake fluid, which ever comes first.