[Devildog9999]

Hey All,

Just changed out all 4 calipers, both master cylinders, and all new pads. Using a vacuum bleeder, I bled everything in the correct order and I have a nice firm pedal for the rear, but I can't get any pressure in the front. I did bench bleed both MC's, and retested with the finger method for the front. Over 3 quarts of fluid through the front brakes and they are still sloppy unless I press on the rears a little bit, then they firm right up.

Anything I should look for? I am at a loss. Should be an easy job.

Thanks!

 

[bp405]

Did you use OEM calipers and master??

 

[Devildog9999]

I didn't, but I picked ones that were mid range. Had the same problem before I started swapping parts though. Just not sure what is causing it.

 

[bp405]

The common denominator is the rear caliper the the rear master operates. There is a seal that separates the two independent systems. The seal is either not sealing or has become dislodged.

Have you bleed the rears with the foot pedal.

 

[Devildog9999]

Yeah, rears are all bled and very firm. Fronts will only firm up if I hold the foot pedal down a bit. Once I let go of the fronts, they go back to squishy again.

 

[bp405]

Well when I can't get them to bleed I raise the front of the machine off the ground pretty high. Either by lifting with a standard floor jack until it maxed out which is about 20" or by driving the machine up on car ramps. Then start the bleeding process over.

 

[Devildog9999]

I did have the front jacked up by itself. I wasn't that high though. Any idea why I have to slightly press the rear to get the fronts to get firm?

 

[bp405]

Cause the rear is operated by the foot pedal and the hand brake. That's why there are 2 bleeders and 2 brake lines going to the rear.

 

[Devildog9999]

Mine has a single bleeder on each rear caliper, as well as a single bleeder on the rear master cylinder. Then one bleeder on each front caliper. It almost seems like the front doesn't have enough presure to push the cylinder in on the rear master cylinder. Once I give the rear foot pedal maybe 1/4 travel, the fronts grab and get firm.

 

[bp405]

Ok bud we are out of my wheel house and above my pay grade, we need reinforcements. I was checking out the parts schematic and see what you are saying. BTW what you describe comes up as an ATP model. So your set-up is a little different then what Polaris typically has and is doing. So where I am having an issue is where the front master ties into the rear. Can't make that out from the parts schematic. Also 2004 was an oddball year as Polaris switched up body designs mid-year. So your 2004 500HO maybe a 2004.5 which is really a 2005.

So while we are waiting on one of the members with more knowledge of your machines system. Were you able to bleed the rears via the handle bar brake lever??

 

[Devildog9999]

I totally forgot to say it was the ATP, sorry about that. I bled the rear calipers with the foot pedal. I bled the rear MC with the handlebar lever. Tha part number for mine is 1910637 for the rear MC.

 

[polman500]

Sounds like you still have air trapped in the main line from the front MC to the foot MC.
You say you "bled everything in order"...
Did you bleed the main line # 6 from the handlebar MC to the foot MC FIRST?
IIRC you have to start by bleeding that line first using the hand lever and the bleeder on the foot MC?
Then go to the LR caliper and bleed it using the foot MC only and then do the RR again using ONLY the foot MC.
Then you go to the RF and use the hand lever to bleed it and then do the same with the LF the closest caliper.

 

[Devildog9999]

Yessir, followed it to the letter. Every bleeder was done excessively until all new clear fluid, no air via vacuum pump. I can do it again though if you think that would help. At this point all I want is brakes.

 

[polman500]

Hmmm... Sounds like you've done everything I would.
Maybe the foot MC is bypassing fluid until its pressed a little is all I can think of. Is it a knockoff?
Does the foot MC reservoir fluid level rise when you press the hand lever? If so, that would indicate its bypassing fluid.

 

[Devildog9999]

I will check that in the AM and report back. Never thought to check that.

 

[Devildog9999]

So I went out this morning and checked. No rise in fluid level to the rear MC when using the foor pedal or the handlebar lever. I am open to any other ideas or suggestions.

 

[polman500]

No, I wouldn't expect it to with the foot but thought it might with the hand lever if it was bypassing fluid.
You might try riding it some and shake it up. Hit up some inclines and down some and heat the system up a little to see if anything changes??

 

[Devildog9999]

I won't be able to until this weekend when I head to camp. I'll give it a shot. Should I try to bleed the main line again?

 

[polman500]

I won't be able to until this weekend when I head to camp. I'll give it a shot. Should I try to bleed the main line again?

Couldn't hurt to go over everything again I wouldn't think.

 

[bp405]

I'd do it again but remember to get the front up high. Not to the point the masters won't hold fluid but high enough that you're forcing those air bubbles up and out.