angelfj1
Yoda
Offline
This was to be brake job weekend for the TR250, but I just hit a snag while replacing the left rear wheel cylinder. This is a brand new part purchased from one of the big three.
Here's the problem - I should have checked in advance before I secured the new wheel cylinder to the back-plate but I didn't. When trying to attach the brake line fitting I encountered more then usual resistance. I have learned the hard way not to force things, especially when screwing steel into aluminum. So, I stopped and removed the wheel cylinder to have a better look. The threads appeared OK, but I put the wheel cylinder in the vise and used and old but clean fitting to chase the threads. Boy, something is wrong here, there is way too much resistance. After very carefully using the old fitting as a tap, I removed it and looked into the bore. Oh boy, I see aluminum shavings! It appears that the tapping operation was a bit shallow (in my opinion) and if you're not careful, you can end up with small metal shavings in the passages of the cylinder - possibly bloking the flow and resulting in no brakes or maybe a stuck cylinder. I intend to notify the vendor on Monday, but I think I'm OK to proceed. I believe the important thing is that the threads are not intended to seal. They provide mechanical leverage to push the brake line flare against the seat in the cylinder body. Once I got everything cleaned up the line snugged up real good.
Look out for this possible problem and be careful.
Here's the problem - I should have checked in advance before I secured the new wheel cylinder to the back-plate but I didn't. When trying to attach the brake line fitting I encountered more then usual resistance. I have learned the hard way not to force things, especially when screwing steel into aluminum. So, I stopped and removed the wheel cylinder to have a better look. The threads appeared OK, but I put the wheel cylinder in the vise and used and old but clean fitting to chase the threads. Boy, something is wrong here, there is way too much resistance. After very carefully using the old fitting as a tap, I removed it and looked into the bore. Oh boy, I see aluminum shavings! It appears that the tapping operation was a bit shallow (in my opinion) and if you're not careful, you can end up with small metal shavings in the passages of the cylinder - possibly bloking the flow and resulting in no brakes or maybe a stuck cylinder. I intend to notify the vendor on Monday, but I think I'm OK to proceed. I believe the important thing is that the threads are not intended to seal. They provide mechanical leverage to push the brake line flare against the seat in the cylinder body. Once I got everything cleaned up the line snugged up real good.
Look out for this possible problem and be careful.
Hey Guest!
smilie in place of the real @
Pretty Please - add it to our Events forum(s) and add to the calendar! >> 