Stuck screws on master cylender help

So for my saturday festivities Iam trying to remove the screws on the top of the master cylender on my xj maxim they are rusted and striped what is the best course of action?

Second I have noticed that two of my headers are leaking around the case. Could that be causing some of my ideal problems

Finaly when I changed the oil (thanks for yalls helP!) I noticed some shavings on the plug. The bike has 55,000 miles on it is that normal, or am I done fore. It shifts fine by the way. thanks for the help.

 

Could you specify or give us a picture of witch screws.
But generaly give it some heat, put the screwdriver in the screw give it a stroke with a hammer and try to get it of.
I have had great experience with an electric air heather (gives up to 500 deg. C).

 

impact screwdriver cost me $20 at the auto parts store

 

been there done that. on the new seca i just bought i soaked those screws with liquid wrench with a squirt a day for 5 days. then find a good screwdriver that fits well. then i lightly tap on the head of the screwdriver while putting turn out pressure. go slow dont strip the screws. with practice you lean how aggressive you can get without brakeing anything. i do this same trick on engine cover scres also. if all else fails order some new screws first. then drill the head off and use vise grips and heat. your going to find more stuck screws than not on these old bikes.

 

These are the srews

 

The hammer trick worked! Man I have never seen brake fluid look like that should I just soak the resivor in brake cleaner. Yuck! I will completly drain all fluid and put new fluid in

 

my master cylinder lookded like a cat puked inside. flushd that and the brake lines out before bleeding the system. amazing what you can do with a good screwdriver and a few light smacks with a hammer. most will come out without stripping if you go slow.

 

Make sure you clean the pressure relief hole in the floor of the master cylinder:


MASTER CYLINDER REBUILD PARTS:

mc41) OEM and aftermarket brake MASTER CYLINDER REBUILD KITS contain all the operational parts you need to correctly rebuild your master cylinder: piston, piston seal, piston spring, piston rubber sealing boot, and retaining circlip. NOTE: the piston seal does not come pre-installed onto the piston, and at first glance, you may wonder "how the heck do you get that small seal opening over that large piston?". Well, lots of lube (brake fluid) and patience and a small, dull pry tool works wonders. Make sure that you install the seal with the flared seal "lip" facing towards the fluid outlet!

Yamaha actually specifies that your master cylinder should be rebuilt every 2 years.

Master cylinder rebuild kits contain the piston, the piston seal, the spring, the plunger end seal, the plunger dust boot and its retaining circlip.


An pictorial overview of the master cylinder rebuild process can be observed at:

http://xjbikes.com/Forums/viewtopic/t=18377.html


NOTE1: be sure you very carefully clean and inspect your used, original master cylinder for any damage and rebuildability. If the pressed-in steel piston bore is badly scarred or pitted-rusted, then it must be honed to a silky-smooth finish before installing new components. If pits or scratches are too deep to be removed, it is best to obtain a replacement master cylinder (new or used) rather than to try to rebuild a damaged original. Remember, your life literally depends on your brakes....not always in day-to-day riding, but when it counts the most, in an emergency situation; and those always happen in the blink of an eye, and without prior warning.....


NOTE2: All original Yamaha front master cylinders have an extremely tiny "blow back" hole (actually a pressure release return passage) in the center of the bottom of the reservoir floor that must be clear and un-blocked in order for your master cylinder to function properly----if this hole is plugged, it will prevent the calipers from fully releasing when the brakes are NOT being applied, causing the brakes to always be slightly engaged. Brake system "dragging" will result, as well as brake rotor over-heating and warpage after a period of time.

This tiny hole is located within an area that is best described as what appears to be the beginning of a drilled hole that was "never completely drilled through" (this will make sense when you actually view the floor of the reservoir). In the very center of such area is this pressure release passage, and it takes about 1-2 un-stranded strands of wire to poke through this hole and remove any debris or gunk. This hole is not the much larger reservoir-to-piston chamber fluid transfer hole, which is huge compared to this pressure-relief passage. The pressure relief passage hole is normally just to the "side" or "behind" the larger (1mm diameter) fluid transfer hole, and "in line" with the centerline of the piston chamber, but "behind" the fluid transfer hole, towards the brake hand lever side of the master cylinder.

When rebuilding your master cylinder, make sure that this tiny relief passage is free and clear! Failure to clean this passage fully is one of the major over-looked "gotch-ya!" situations that arise when rebuilding your master cylinder.


A good picture of this relief port on the conventional (handlebar-mounted) master cylinders can be seen at:

http://www.xjbikes.com/Forums/viewtopic/t=12529.html

 

Nice job! I had the same problem and ended up drilling out the old screws and replacing them with some new ones from the hardware store

 

Nice job! I had the same problem and ended up drilling out the old screws and replacing them with some new ones from the hardware store

 

Drill them right out and don't worry about leaving a fragment.

You can Drill-off the Head
Remove the cover and Diaphragm Gasket.

Grind the Fragment.
Center Punch the Fragment.
Drill the Fragment right out.
Tap the Hole and don't forget to enlarge the Hole on the Cover.
Use a "Single Hole" Paper Punch or a Leather Belt Hole Cutter to cut a new pair of Holes in the Diaphragm Gasket.

Tap New Threads.
Use some Stainless Steel Cap Screws as New Fasteners.