109 brake problem

Fitted new rear wheel cylinders and copper pipes from the 3 way splitter to the cylinders yesterday and bled them up for ages and ages but I,m still not getting any pedal.the previous **** that owned it ran the old girl just on the front brakes after he stripped the threads in both rear cylinders and attempted to sort it by putting them back in with PTFE tape
So anyone have any ideas what the problem might be or is it just a case of bleed,bleed,bleed until I get somewhere?
Cheers

Assume you have bled the front wheels as well

if you clamp off the rear flexi and the front two flexis, if no air in that bit you should get a hard pedal, if its still soft suspect the master cylinder seals, MC leaks, pipe leaks. seals prefer to fail in cold weather

if its hard remove a front flexi, if pedal goes spongey then problem that side, if its still hard remove the other front flexi , if it goes soft then problem at front, if still hard remove rear flexi and you have located the area of problem.

keep master cylinder topped up

check bleeding technique

the pressurised bleeding kits that work off the tyre pressure are good or even the one way valve bleed pipes

Cheers Steve.I,ll give that a go in the morning.
My 109 doesn,t have rear flexies mind?

perdix said:

Cheers Steve.I,ll give that a go in the morning.
My 109 doesn,t have rear flexies mind?

Click to expand...

You have a central flexi at the rear (I hope!!!!)

I,ll have to have a look but I can,t remember seeing one

Thought there should be something like that there but gave up looking after smacking my head off the axle and bleeding everywhere :doh::lol:

they are an utter pain to bleed, i have the same problem on mine everytime i need to bleed the brakes its nearly always the front, the easyest way i know of is to remove the backing plates on the front leaving shoes attatched and turn it so the bleed nipples face upward, this is possible with the flexi
by doing this is stops the air lock in the wheel cylinders. once you have done this the brakes are easy to bleed. its nearly always the front on 109 brakes due the twin leading shoe

Another way with the front is to bleed the top cylinder by partially undoing the union that runs between the cylinders. Bit of a pain and you need a helper but works well. Bleed at nipple 1st as normal then pump up brakes hard and undo union and pinch up again at bottom of brake pedal stroke. You need plenty of rag to prevent fluid getting everywhere but a couple of strokes will do the job. I bleed again at the nipple just to be sure

Cheers Blue Beasty ,I will try that tomorrow as my assistant is having a bloody pyjama day and she,s refusing to come out and play
Found the flexi and after clamping it off the brakes are solid so the air is definately at the rear of the Landie.
Onwards and upwards

Are you sure the springs are in the right positions ?
If you give a couple of pumps I take it the pedal is good for a second or so ?
Take off the resivour lid pump the pedal and get somebody to watch the fluid level, if it starts to come up while the pedal is pressed then the springs are to tight and they are squeezing the whole lot shut

pobby said:

Are you sure the springs are in the right positions ?
If you give a couple of pumps I take it the pedal is good for a second or so ?
Take off the resivour lid pump the pedal and get somebody to watch the fluid level, if it starts to come up while the pedal is pressed then the springs are to tight and they are squeezing the whole lot shut

Click to expand...

The springs looked to be ok Pobby but the be honest when I put the new cylinders in I spragged the shoes open and never removed the shoes or springs
I,ll check that as well tomorrow cheers

If the flexi is old or has been stretched they can balloon......doesn't take a lot as the volume of fluid shifted is pretty small

109party said:

they are an utter pain to bleed, i have the same problem on mine everytime i need to bleed the brakes its nearly always the front, the easyest way i know of is to remove the backing plates on the front leaving shoes attatched and turn it so the bleed nipples face upward, this is possible with the flexi
by doing this is stops the air lock in the wheel cylinders. once you have done this the brakes are easy to bleed. its nearly always the front on 109 brakes due the twin leading shoe

Click to expand...

OK.I,ll look at that too.
Found trying to get to the bleed nipples on the front axle a bloody pain in the arse to he honest and maybe didn,t spend as a long as I should have bleeding them.
My old 88" was never as much hassle as this but I,m coming to the conclusion that this old girl is worth it.Reckon she has been stood a while as there is a bloom on some of the bits(glow plug terminals,master cylinder etc)
Got to say that I wasn,t looking forward to coming back to 4 wheels after doing the bike club thing for 4+ years but having a big fook off mechanno kit is growing on me once again.Still wish I,d waited for an 88" mind you

blue beasty said:

If the flexi is old or has been stretched they can balloon......doesn't take a lot as the volume of fluid shifted is pretty small

Click to expand...

Might replace that as well for how much they cost then mate
Bikes are so much and I,ve built them from the frame up

Well I,m still struggling with these frigging brakes

Still got some braking but when the pedal is depressed(or is that me!) there is no gradual application of the brakes.Its like treading on a house brick but the pedal goes about 1/2 way down to the floor?It also does stop but not as well as my old SWB did.
I clamped the rear flexi and that gave me the same effect but the pedal only went 1/4 of the way down .Still the same really solid feel though.I looked again at bleeding the front brakes but one of the nipples is rounded off!
Wondering if it has servo issues to as wether its running or not there seems to be little difference in the feel of the brakes.Want to get it sorted as I,m tempted to move the old girl on in favour of a SWB and theres no way it can be done til this is 100% right.
Its a later servo-assisted dual system so any ideas please chaps?

If you have a servo fitted you need to run the engine whilst bleeding your brakes!

Otherwise it just don't happen!!

:doh:

Cheers Oldseadog.
Looks like a Boxing Day job then

What's wrong with doing it early on tomorrow as it gets light??:bolt:

Cos I,ll be busy opening all my pressies