Brakes not releasing?
Check your Master Cylinder "Spooge Holes"
by Ken Talbot, 6/20/00
Many XSives have experienced a problem with brakes not fully releasing or even locking up completely. This can be caused by a clogged fluid return orifice in the master cylinder. When this orifice or "spooge hole" is obstructed, pressure builds in the caliper.
Just in case anybody was wondering where the smaller orifice is that everybody talks about getting all spooged up.... Procede as follows:
Front
Protect the tank with lots of rags
Remove the cover
Use an old baster to remove the fluid
Gently twist and pry off the reservoir
Remove a litle more fluid
Be sure not to squeeze the brake lever
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Note the curl in the end of the wire so it can't be accidently dropped right through while cleaning the orifice.... The wire diameter needs to be .015" or smaller (that hole is small), don't enlarge the hole with a drill or welder tip cleaner!
Rear
11/30/00
There is a second, smaller orifice in the rear MC for relieving the line pressure when you let up on the brake pedal. It's just not as easy to find and clean as its counterpart in the front MC.
Remove the right hand side cover. Remove the MC lid, remove the brake fluid with a baster, pry the plastic reservoir up gently with a small flat bladed screwdriver. Remove more fluid with the baster, then sop up the last bit with a clean rag or piece of paper towel.
Remove the two mounting bolts so you can list the MC high enough to clear the actuating rod. Let the actuating rod fall out of the way to the rear.
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Drop the MC down low enough to remove the plastic reservoir. Pull the MC back through the plastic inner fender and twist it to the side a bit so you can get at it.
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Look inside and you'll see two holes - a big one on the top and a smaller one on the bottom. The spooge hole is actually drilled exactly in the middle of the larger, upper hole, not in the lower hole.
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To see the spooge hole clearly, you need to remove this drain plug from the bottom of the MC so you can look inside with a flashlight.
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With a bit better light, you would see the hole drilled dead centre on the top. I just couldn't get the light right for it to show on this photo, but trust me, it is there.
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You could fish a long wire in through the drain plug bore for cleaning the spooge hole. Or, you could use the same little wire (with a curled end) you used on the fromt MC and poke it into the hole with a pair of needlenose pliers.
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By just poking around with the pliers, you will feel the wire slip into the hole. Slide it back and forth a few times and you're ready to put it all back together. If you've been careful not to press the brake pedal before you got the MC lifted clear of the actuating rod, you can get it all back together and refilled with fresh fluid without introducing any air into the lines.
Of course, if this resolves a problem, chances are that you should be removing the MC for a complete strip down so there is no possibility of more spooge breaking loose and replugging the orifice. Then this turns from a one hour job to something "a little longer".
Like I said, not as easy as the front MC, but it still can be done.
Check your Master Cylinder "Spooge Holes"
by Ken Talbot, 6/20/00
Many XSives have experienced a problem with brakes not fully releasing or even locking up completely. This can be caused by a clogged fluid return orifice in the master cylinder. When this orifice or "spooge hole" is obstructed, pressure builds in the caliper.
Edit: This is a common problem, but what needs to be pointed out here is if you have this problem, your brake fluid has serious contamination. This 'fix' should ONLY be considered as temporary; you can attempt flushing the system to get rid of the contamination, but that is rarely a long-term repair; the only sure way to eliminate this is to completely disassemble the system and fully clean it, refilling with new fluid. Another cause of dragging brakes is internally corroded calipers; corrosion behind the caliper piston seal can 'expand' the seal, preventing the piston from retracting when the brakes are applied. To determine which issue you have, if you have a dragging brake try 'cracking' the bleed screw on the brake caliper; if the brake releases, it's in the master cylinder, if it doesn't it's a caliper problem. In either case, it's HIGHLY RECOMMENDED that you COMPLETELY disassemble the ENTIRE brake system, thoroughly cleaning everything and replacing parts as needed for safe, trouble-free brakes.
Front
Protect the tank with lots of rags
Remove the cover
Use an old baster to remove the fluid
Gently twist and pry off the reservoir
Remove a litle more fluid
Be sure not to squeeze the brake lever
Note the curl in the end of the wire so it can't be accidently dropped right through while cleaning the orifice.... The wire diameter needs to be .015" or smaller (that hole is small), don't enlarge the hole with a drill or welder tip cleaner!
Rear
11/30/00
There is a second, smaller orifice in the rear MC for relieving the line pressure when you let up on the brake pedal. It's just not as easy to find and clean as its counterpart in the front MC.
Remove the right hand side cover. Remove the MC lid, remove the brake fluid with a baster, pry the plastic reservoir up gently with a small flat bladed screwdriver. Remove more fluid with the baster, then sop up the last bit with a clean rag or piece of paper towel.
Remove the two mounting bolts so you can list the MC high enough to clear the actuating rod. Let the actuating rod fall out of the way to the rear.
Drop the MC down low enough to remove the plastic reservoir. Pull the MC back through the plastic inner fender and twist it to the side a bit so you can get at it.
Look inside and you'll see two holes - a big one on the top and a smaller one on the bottom. The spooge hole is actually drilled exactly in the middle of the larger, upper hole, not in the lower hole.
To see the spooge hole clearly, you need to remove this drain plug from the bottom of the MC so you can look inside with a flashlight.
With a bit better light, you would see the hole drilled dead centre on the top. I just couldn't get the light right for it to show on this photo, but trust me, it is there.
You could fish a long wire in through the drain plug bore for cleaning the spooge hole. Or, you could use the same little wire (with a curled end) you used on the fromt MC and poke it into the hole with a pair of needlenose pliers.
By just poking around with the pliers, you will feel the wire slip into the hole. Slide it back and forth a few times and you're ready to put it all back together. If you've been careful not to press the brake pedal before you got the MC lifted clear of the actuating rod, you can get it all back together and refilled with fresh fluid without introducing any air into the lines.
Of course, if this resolves a problem, chances are that you should be removing the MC for a complete strip down so there is no possibility of more spooge breaking loose and replugging the orifice. Then this turns from a one hour job to something "a little longer".
Like I said, not as easy as the front MC, but it still can be done.
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