Siezed Front master cylinder filler cap bolts

[Tecate250]

On my 250r the filler cap for the front brakes is missing a bolt and the other one is siezed good in there. If I had a spare cap id cut the old one off and remove the bolt with vise grips. There is alot of fresh brake fluid in there but would like to drain the old stuff out and put in 2 bolts that will come out. :wondering

[jb2wheels]

Do you have a hand held impact driver for screws? They're like $10 if you don't and a lifesaver for this kind of stuff.
http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=37530

Soak in your favorite penetrant then use the impact driver.

[Xhumeka]

Do you have a hand held impact driver for screws? They're like $10 if you don't and a lifesaver for this kind of stuff.
http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=37530

Soak in your favorite penetrant then use the impact driver.

+1

An impact driver is almost a necessity to work on these old machines!! I had a stripped master cylinder filler cap screw as well, so I took a dremel and cut out a nice slit for my impact driver to catch... worked like a charm (except the top cap of the filler now has a small slit in it as well)

[atc350xer]

+1

I had a stripped master cylinder filler cap screw as well, so I took a dremel and cut out a nice slit for my impact driver to catch... worked like a charm (except the top cap of the filler now has a small slit in it as well)

Ditto for me with my 350x, but I found something out... household light switch/receptacle plate screws work nicely when you get those old rusty screws out... that's what's holding mine on

[Tecate250]

Hehehe Yeah I tried the impact driver with no use. Also used a dremel to cut a flat head and still nothing. But I didnt want to beat too hard on the master cylinder incase i broke it.

[Xhumeka]

You can always try an impact wrench (air) - if that won't turn it, then you're probably going to be forced to drill it out :(

Like mentioned above, soak it a few times with PB Blaster before trying again...

[JohnR.]

You are all forgetting about the most effective way to remove a stuck bolt. Heat. Get at it with a propane torch. Just don't get too crazy or you'll mess up the seals on the piston. Personally, I'd spend the $30 or $40 for an LTR450 or YFZ450 one.

John

[atc350xer]

It's a master cylinder screw... you heat that, you'll damage the rubber diaphragm... I used an oversize drill bit to get rid of the screw head... no damage to the cover... then popped the cover and used vise grips on the screw... replaced them with light switch plate screws

[JohnR.]

If you're careful with it you'll probably be OK. Besides, I'd rather buy a new diaphragm than deal with a screw being snapped off inside the MC housing. For me, rather than dick around with a 25 year old master, I'll spend a few bucks on one from a newer machine that gives you a much better feel, has a cap that comes off easily, and has an adjustable lever. Also, rather than use light switch screws, I'd go to the hardware store and find some stainless screws that will fit in the holes.

John

[atc350xer]

yeah... I'm a cheap b*stard :D
now that I'm thinking about it, NAPA carries metric screws

[JohnR.]

LOL! I can be a cheap fuhk too but if its going to save me aggravation I'll always spend the money.