Rear drum Brake Woe's Page 1 / 2

ginga4lyfe, Feb 24, 8:45am
**Rant** Why is it soooo hard to bleed Triumph 2500tc's rear brakes! also No matter what i do the hand brake wont hold the car, besides the brake cable half breaking it should still have enough tension to hold the car, but noopppeee gagh. im just annoyed coz i spent 2 hours trying to bleed the rear brakes after replacing the Cylinders and yet after i think im done, as soon as i jump back in the car after tidying everything up, the brake pedal has gone soft again!, Im going to replace the brake balancing unit tomorrow and then see how i go, and then hopefully i can get the car high enough so i dont have to struggle as much to get under the thing, So I gotta ask, does anyone have experience with bleeding the 2500tc brake system! what worked best for them. coz Haynes method doesnt seam to be working well.

jmma, Feb 24, 8:54am
Make sure your bleeding nipples are in the top holes of the cylinder, with the handbrake, back off cable and adjust brake shoes first

ginga4lyfe, Feb 24, 9:15am
yeah. that dont work, the brakes are auto adjusting, so is the hand brake, I can only adjust for cable stretch ( which i seam to not be able to get rid of ), and, the nipples can only go in one way, facing downwards, on the bottom of the cylinder, on the bottom of the drum, its how it was designed, and why im having a fit over bleeding problems

ginga4lyfe, Feb 24, 9:24am I took a pic of the drum brake diagram in the haynes manual, its slightly wrong though, because the bleed nipple is on the bottom, not were it shows the nipple supposedly going to

jmma, Feb 24, 9:25am
Are you sure you have cylinders in correctly, bleed nipples should be at top, air gets trapped in top of cylinder, and all auto adjusters on older cars can be adjusted manually.

ginga4lyfe, Feb 24, 9:36am
Yes, 100% sure, they have a locating pin to prevent them goin in any other way and the holes are differant sizes so that the line in can be secured with a c clip, and if i some how managed to get the cylinder in upside down, then i would never be able to get to the nipple anyways and the nipple is on an angle that the lines would never be able to get to the cylinders with out breaking ( metal lines ), yes I know its a messed up system, and its the reason on why im having trouble bleeding it i guess, but I suppose thats what you get outa the 70's from the british that were more interested in the shape of a tea cup than the car they were driving

jmma, Feb 24, 9:40am
Well try bleeding from the brake pipe, you must bleed the air out of the top of the cylinder

im_andrew, Feb 24, 9:41am
Try adjusting the brake shoes out manually first. Auto adjusters are generally shit and dont work very well. When the rears are properly adjusted, try your pedal then.

ginga4lyfe, Feb 24, 9:45am
Ill give it a try, Would you know if the adjustment works directly in relation to the hand brake! the book is a little sketchy on this, infact. im not sure why it carrys the haynes name, its terrible compared to my Morris Marina Haynes manuals ( even the lesser auto data manual is a better example on the marina than the haynes triumph manual! )

jmma, Feb 24, 9:48am
Back off cable and remove drum, ease out both shoes with 2 screw drivers slowly, you will hear a click, do one click at a time and keep putting drum back on, you will feel when its right

ginga4lyfe, Feb 24, 10:10am
Cool, i will do that, I just realised something that may be a contributing factor though, would it effect the brakes if i took one completely appart, and reset the adjusters, and not done the same ( reset the adjusters ) to the other side!would it cause this! coz i would have thought that it would have pulled equally and naturally reset the pads, but then also thinking about htat, maybe it would only be pulling on one side as the pressure bias may be offset to the correctly functioning drum! I dunno. its been a LOONNGGG day ( waking up at 3 am to see if the Parents are going to the airport to help out with civil defence and all )

jmma, Feb 24, 10:16am
Yes, one step at a time, back all adjusters off and do one wheel at a time

im_andrew, Feb 24, 10:18am
Can you take a photo of the shoe assembly and post it! There should be a slot in the back of the backing plate that you can slip a screwdriver through to turn the rachet and adjust it.

Im not familiar with old triumphs, but this is how every other drum brake assembly Iv seen has been.

ginga4lyfe, Feb 24, 10:28am
, I Dunno if the link above is actually visible to you, it does give some idea of what its like, and I know what you mean, but nah, it doesnt have that roller style adjuster, its got this weird plate that has teeth on the top were another spring loaded plate with teeth sits on top and stops it un-adjusting itself, the only way to back it off is by lifting that spring loaded one and forcing the adjusting plate back to its "normal" position, Ill take pics tomorrow for sure, tbh, id be out there right now working on it if the neibors didnt mind the radio blaring, a light shining from the carport, and it was slightly warmer outside . and the mosquitoes didnt like me soo much

ginga4lyfe, Feb 24, 10:34am I grabbed another photo from the book, hopefully this gives you an idea of what its like, the yellow arrow is pointing at it, its on the back of the shoe, displayed as a dotted line

jmma, Feb 24, 10:37am
This is the only way to do that type

richardmayes, Feb 24, 5:54pm
Do you mean the unit in the engine room, where the 2x master cylinder lines and the 2x lines to the wheels all meet! There's no need to replace this, all it is, is an electrical switch that makes the dashboard "Brake" light go if there's an imbalance between one master cylinder and the other.

I think the only problem with your brakes is the person bleeding them (I say this because I'm rubbish at it too!)

kenw1, Feb 24, 6:57pm
Check the floor pan, where the handbrake bolts onto, we found that it was cracked enough to allow flexing of the handbrake and half the tension was going into that, did some reinforcing and the handbrake worked heaps better.Had problems every time with the rear brakes.It really is a case of working very methodically through the whole setup, when they are working properly they are good.Check the adjusters really do adjust, as well.In the end used to tighten them up for the WOF and release them a bit afterwardsw\.

budgel, Feb 24, 8:05pm
Check that any rubber brake lines arent past their use by date and expanding.

ginga4lyfe, Feb 24, 9:24pm
Done, they done seam to expand, only stiffen, but by all means the lines arnt soft otherwise

sr2, Feb 24, 9:54pm
Right, here we go. From memory (and we??

ginga4lyfe, Feb 24, 10:48pm
, so even once the system is purged the brakes feel spongeyish and need pumping to stop the car (faster ) untill you have driven it around and pumped it up!,

anyways, iv dug into it, and i am pretty sure i have adjusted the handbrake properly now, it does take some fideling, but not too hard, but still after bleeding the system again ( 3 times soo far ) the brakes still seam spongey. Im used to the brakes going rock hard, I may have to bleed them overnight as SR2 says , but im not exactly sure on how to do so, I may just go buy a looonnnggg clear hose to put onto the nipple to lead it back to the Reservoir, and just pump it untill i got a constant circulation!

ginga4lyfe, Feb 25, 1:38am
the hand brake works ok now, but the pedal still needs to be pumped up to work properly, iv tried a few methods to bleed the brakes, nothing seams to be working, this is starting to become a joke, its like there is a massive pocket of air that wont budge

toyboy3, Feb 25, 1:45am
clamp all 4brake hoses,if you do not have hose clampsthen use visegrips but do not be hard on clampingor hose will be damagedthen test the brake pedalif okayrelease one hose clamp untill the pedal goes softand there is the problem area

smac, Feb 25, 1:47am
I don't know squat about Triumphs, but to go out on a limb here I'd say the book is right and your cylinders are on the wrong sides so the bleeds are at the bottom.

I DO know about bleeding crap old systems- and I now recommend staying away from 'long slow strokes' (oo err) because you end up causing the master cylinder seal to travel into a nasty half corroded portion of the cylinder bore that it doesn't normally sweep and you now have a leak (ie you will never get that spongy pedal to go). A pressure bleed unit that runs off a car tyre (or even bike pump) was one of the best tools I ever bought. Can be run at very low pressure to avoid any aeration.

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