master cylinder screw

[thebig450es]

Im almost done with my rebuild, i went to take the cover off my front master cylinder to fill it with fluid to bleed my brakes. One of the screws refuse to come loose. Could i just back fill the system?

[CJM]

Yes you could backfill but it wont be easy.

I had the same problem, try going to sears and getting thier grab it screw extractor tools, or drill out the head carefully and then you have enough to get pliers on.

[NacsMXer]

Originally posted by CJM
Yes you could backfill but it wont be easy.

I had the same problem, try going to sears and getting thier grab it screw extractor tools, or drill out the head carefully and then you have enough to get pliers on.

X2, screw extractor or carefully drill it and use an easy out. Could also use a reverse drill bit. It's a tiny screw so it shouldn't be under much force.

And when you do get the screw out, "backbleeding" the system by injecting the brake fluid from the bleeder valve on the caliper is THE BEST way i've found to bleed the brakes.

I installed a new set of YFZ450 dual piston calipers not long ago, as well as a new 450R front master cylinder assembly. I connected my SS lines to everything and started with a completely dry system which typically is hard to start bleeding.

I used a 60cc catheter tip syringe with a small piece of clear PVC hose attached. Then you basically suck some fresh brake fluid into the syringe, hold it perfectly vertical, and squirt some fluid out until all air bubbles are out. Put the syringe/hose over the bleeder valve, open it, and slowly start injecting the brake fluid. As the fluid starts reaching the master cyl, you will hear it bubbling as it is purging all the air bubbles upward. Air naturally wants to travel up, so you are pushing them the way they want to go, not the opposite with traditional bleeding.

After about 2 or 3 visits with the syringe to each caliper, I instantly had a rock hard brake lever. It was the fastest, easiest, and most effective bleed job i've ever done. I have a Mityvac brake bleeder, and the syringe blows it away in how effective it is. The Mityvac is a ton of pumping, cracking the bleeder open, and repeating.

I had to drive an hour to a vet supply warehouse to buy the correct syringe, and I had to buy a 30 count box. I have a ton left if you want to buy one.

[CJM]

Oh, almost forgot to add: When you put it back together make sure you put some anti-seize lubricant on the threads and you will NEVER have this issues again. That or replace them with allen heads.

[NacsMXer]

Originally posted by CJM
Oh, almost forgot to add: When you put it back together make sure you put some anti-seize lubricant on the threads and you will NEVER have this issues again. That or replace them with allen heads.

X2 again, CJM's on top of things :D

Allen heads work very well, and a thin coat of anti seize is a godsend. I use it on pretty much all my hardware that isn't loctited.

[Scro]

As you are turning the screwdriver, tap on the end of the screwdriver with a hammer. It's easier to have someone help while you turn. If the head of the screw isn't completely FUBAR, this will break it loose.