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87 trailboss 4x4 brakes

3K views 3 replies 2 participants last post by  stave7119 
#1 ·
Hello all,
New to the forum and just inherited an 87 trailboss 250 4x4. I’m having issues with sourcing brake hoses. Two of the 4 are plugged and I think the master cylinder is toast. I’ve scoured the interwebs and Polaris part catalogue and most everything is no longer available. Wondering if anyone has any suggestions for getting the front and rear hoses. Also I saw that the master cylinder seals are still available but once I looked them up they didn’t quite look right. Has anyone ever rebuilt these old masters with new seals?
 
#2 ·
You can check on Ebay or go to powersportsnation.com and see if they have what you need. If all else fails you might be able to make a later model master cylinder work. There are also several companies in the automotive aftermarket that make custom brake hoses.
 
#3 ·
Thank you, I scoured the internet and local dealer to no avail, but I did find some seals for the MC still available. I rebuilt it and tried to bleed it for days! Could not get more than a minute amount of fluid out of it. I decided to try some stuff and I figure out a trick to pre prime the system. I pulled the master cylinder “cylinder” out far enough that the hole in the bottom of the reservoir was open to the brake system but not able to leak out of the master. It flowed like niagra! Then once I felt that was good I pushed it back in and it was hard as a rock. With the help of fluid it moved all the other crud around and I was able to get fluid from all three calipers. Repeated the steps till I was confident that most of the air was gone and I have brakes! I think the rear caliper is seized in the released position but I have front brakes! The other parts will probably hang up eventually but I don’t really care just glad I can semi stop now.
 
#4 ·
Great! I have mostly used a suction gun to pull fluid down to the wheel calipers. That bleeds the master cylinder too. I think you should be able to get a rear caliper when the time comes. Glad you can stop now!
 
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