Kodiak 400, 2007 - Can't bleed rear brakes??

[ESOX]

I had to replace a front calliper so just loosened all three banjo bolts and drained the whole system. Now I am unable to get new fluid to the rear calliper, either by pumping the right side hand brake or with a vacuum on the bleeder bolt. Any ideas on what the problem is?

[davefrombc]

Did you check to  make sure the bleeder  hasn't been  plugged by  dried mud?  You  may  have to remove it to  clean it out. With the bleeder screw out you should see fluid  come to the cylinder.  If not  there is a problem  between the  master  hand operated cylinder and the  brake cylinder.

 

[ESOX]

Thanks for the response Dave. Yes, I removed the bleeder to see if that was the problem. Although the old fluid drained from the banjo when I loosened it, I am not able to get the new fluid to the same banjo.

[davefrombc]

No  idea  on the plumbing on that quad's brake system , but  some of the older cars with  a single  master cylinder feeding both front and rear brakes had  sliding valves to  block the line to  the brakes on front or rear if a line was damaged . The sliding slug  needed to be reset  after repair .  Have you tries "reverse bleeding"  the rear brakes.... Pump  fluid from the bleeder  back to  master cylinder to see if that works ? Otherwise  either the line  is crimped  or blocked somehow between the master cylinder and the brake cylinder.

[ESOX]

Hi Dave - I did try to push fluid from the bleeder back to the master, no luck. I'll check for a crimped line but don't expect to find one as the fluid drained freely. Thanks for your helpful suggestions.

[davefrombc]

Do you develop pressure in the  master cylinder to operate the front  brakes with just nothing going to the rear?  If so , there has to be a blockage somewhere in the  line.  I'd start at the rear cylinder.. Remove the line from the cylinder and see if you  have fluid under pressure from the  hand brake.  If  so, then the trouble is in the  caliper. If no fluid, reconnect it  and go to the splitter where the fluid is divided between  front and rear. If you  have  fluid there , then  go to the next connector and see if  you  have it there.  The blockage will be between the last place you had fluid  and the caliper on the rear.

I  can't find a diagram of the hydraulic circuit  for the brake system  so  I  have to  make  simple guesses and suggestions for things you've probably already tried.

[ESOX]

Yes, the front brakes work.

 

[davefrombc]

When you find out  why you couldn't  bleed the rear brakes please be sure to  post up the solution

[ESOX]

👍

[ESOX]

The Solution - Finally gave up and took the quad in to the dealer. As I had drained the brake fluid completely a large air-lock formed. All that was required was to drain again and start filling from the rear calliper, front left calliper and then front right. Slightly embarrassing but it did provide an opportunity to learn something new, apparently that’s good for us. Thanks again Dave for you help.