Hi lads

Managed to get a bit air in my rear guide brake as the previous owner had too much fluid in system.
I ordered the epic bleed kit and tried to bleed last night. The problem I have is I can’t push the dot fluid from the bottom syringe to the top. The clamps weren’t on and followed the instructions. I took the top off the reservoir of and emptied the fluid out but the brake system was still full of fluid. I can only assume the the plunger in the lever is stuck blocking the port ?? If so can I repair ?

Cheers

Check that any contact point adjusters are wound all the way out.

I did that mate. I’ve just had the lever off the bike and pushed the piston back with a hex key but still blocked. I have filled reservoir with disc brake cleaner and gunk come out of the ports. I’ve left some in the reservoir and will see if it’s cleared when I get back fro the park with the bairn. I’m used to shimano and never have a problem apart from the of calliper leaking.

What the hell are you doing with the brake cleaner?! Get that out of there asap.
It’s probably now mixed with the fluid, you’re going to need to do a very thorough flush with a lot of fluid.

After you’ve flushed it, put the lid back on the reservoir, open both nipples and connect the syringes, and see if it will push fluid through from the lever end.
I suspect you haven’t got the bleed ports open properly.

What made you think it was over full? I’m pretty sure that’s not possible.

Is it the one with the bleeding edge at the caliper? If so I found I had to connect the bleeding edge adapter then unscrew the port using a bit of force for the first time and about 2 or 3 turn before the port was actually open enough to get fluid through.
I wouldn’t be putting brake cleaner through it, probably ruin the internals.

@submarined of course you can over fill them – just bleed them with the piston partially out so when you try to push them back in it fills the lever and has no spare space to move into.

To OP, get the brake cleaner flushed out and start the bleed from scratch following a proper instructional video or take it to a shop to get done. When you say crap came out what do you mean

Overfilling is totally possible, and frequently recommended by people who don’t understand why it might be a bad plan.

It’s what happens when people do a bleed with part warn pads or advance the pistons while bleeding. It used to blow the lever seals in Formulas all the time.

You definitely want the brake cleaner out ASAP and the system is going to need a good old venting followed by a lot of sacrificial clean brake fluid now. It’s possible that the ‘gunk’ was actually from internal seals, so once you get the system back to pressure assume nothing and seriously consider testing extensively in a safe environment where sudden brake failure would be OK before using them anywhere that you don’t want to possibly discover you no longer have brakes.

The only thing you should ever be pumping through a brake circuit is the fluid it was designed to use. Brake cleaner is strictly for exterior surfaces as it’s vicious stuff.

I could help with your issue but as I’m not a lad I’ll leave them to help you out

Given that recent Sram brakes have been known to suffer swollen master-cylinder pistons, i’d guess the OP’s probably hit the nail on the head with his diagnosis of a stuck plunger as it’s exhibiting the symptoms. Replacement pistons are available, though whether genuine ones will go the same way,I don’t know.

PS replacement pistons are fine – did both of mine.

Hi lads thanks for reply’s. The lever wasn’t on the bike when I had the cleaner in. I was planning a full thorough flush anyway but was unable to do it.
I don’t think you can not have the sram bleed ports not open enough as you take the grub screw out as it’s not bleeding edge.
The system must have been bled without the bleed block as when I installed new pads there was only 1mm gap between and there was no way it was pushing back. I stripped the lever down and leaned the ports out in the reservoir. However I damaged the gasket on the lever plunger when reinstalling it. So ordering a new plunger
There was defo a blockage in the port and the fluid that was in was dirty.
I’ve bled shimano brakes and brakes on my cars loads of times so understand the concept. I have code RS on my other bike and have never had a problem.

I could help with your issue but as I’m not a lad I’ll leave them to help you out
Sorry should have also said lasses 😀

Can I just ask what the point of the bladder in the reservoir is ?

If there’s no bleeding edge port on the caliper (if you have you use a small
Allen key or torx bolt – I forget which – to crack the port a tiny bit with it before putting the bleeding edge tool in) then you have the original guide r brakes. Those were the ones where the piston in the lever could swell and seize and can be replaced. Normally happens in very hot weather which seems unlikely at this time of year unless you are somewhere outside the U.K.

Hi joe mines defo not bleeding edge.
I’m ordering a piston from fleabay or Amazon. I’ve just popped an elixir lever on till it arrives as I can only find them from Chinese sellers. I Boe the elixir with ease.
I think the piston was only slightly sticking and the main problem was the blocked ports in the reservoir.