Steering Brake Master Cylinder Sticking

[Avenger Bob]

The left turn brake is dragging on my 2004 Avenger causing the disk on that side to overheat and the vehicle pull to the left and stop. It would appear that the master cylinder for that side has seized although it may be the caliper - I am not absolutely sure which, but since the master cylinder piston seems to be retracted and the little push rod for that side is loose I am guessing it is the master cylinder. The machine is stranded at my cottage and not near a dealer so I would like to know what parts to take up to fix it. Is it worthwhile rebuilding the master cylinder or should I just replace it? Do these things rust or just get dirty? What are the chances it is really the caliper and not the master cylinder? Has anyone had any experience with this problem?

[curtisbyrne]

it may need to be set properly,or the seals could be getting bad in the calliper.you could also just take the calliper off and clean it up they do get dirty and gumed up but while its off its just as well to redue the caliper to save work in the long run.

[Avenger Bob]

it may need to be set properly,or the seals could be getting bad in the calliper.you could also just take the calliper off and clean it up they do get dirty and gumed up but while its off its just as well to redue the caliper to save work in the long run.

Thanks Curtisbyrne, How about the master cylinder? Do they get gummed up or rusty?

[wedge]

The piston in the master will get sized in the housing . Best to spray with gum cutter and then some WD40 or penatrent to losen up !

[curtisbyrne]

correct! clean out the whole brake system of brake fluid and check everything

[Avenger Bob]

Thanks gentlemen. I will look at it tomorrow and report back

[ARGOJIM]

Before you do anything check this.
Remove the firewall and look at the 2 tangs the plungers stick through, if they are not in a straight line across from each other bend them out, hard (handlebar) turns can bend the tangs towards the front of the machine causing drag on the brake system.

[Avenger Bob]

Before you do anything check this.
Remove the firewall and look at the 2 tangs the plungers stick through, if they are not in a straight line across from each other bend them out, hard (handlebar) turns can bend the tangs towards the front of the machine causing drag on the brake system.

Thanks Argo Jim, Will do.

[Rory_mcw]

Do you run it on tracks as per your sig?

I would:
As argo jim says - Remove the firewall, check the Tangs are not bent, if they are bent in check your master cylinder piston adjustment. With that done remove the master cylinder cap/cover of the side that is sticking, operate the brake and you should see fluid moving inside it - continue to do this to make sure the calliper is moving correctly. If the calliper is binding- remove the pads, check that the wear across the pad surface is even - the reason I ask if it is on tracks is with the early avengers (non hdi) and tracks (especially on back ground) is that when turning, the machine is harder to manoeuvre, causing the operator to apply more force to the handle bars. These alloy callipers will splay out at the bottom (you will see this) causing the top of the pad to contact the disk, wearing the pad unevenly - the pad will then try to sit flush on the disk when the brake is applied causing the piston to hang up in the calliper.
Also: if the Tangs are bent, check the 2 bolts that sit on the alloy steering quadrants. The early machines had a Allen bolt to retain the brake cable on the right side, it can be ground down or replaced with a flatter type Allen head (cap) bolt. From memory the brake upgrade kits (with the pulley) may come with button head cap screws/bolts.

I would take with me the following:
1 x brake pad set
Calliper split pins
500ml brake fluid
Basic tooling
Steering rod assemblies

As a back up:
Calliper
Banjo bolts and washers (incase you loose one inside)
Master cylinder

Rory

[Avenger Bob]

Thanks gentlemen. I will look at it tomorrow and report back

I did check the tangs as per ARGOJIM's advice and found that the plunger pins were loose. The pin for left turns had actually come out of the recess on its steering arm and lodged against the arm in such a way that it was not allowing the piston to fully release. I put the pin back into position, adjusted them correctly and the problem is now solved. Adjusting these pins is part of the prescribed maintenance in the owners manual and I can now see why! Thanks for your help!