Technical stuff > Brakes
Beta handbrake not holding vehicle on a slope
Gromit:
Greetings Beta owners from down under. :) Been a while since I communicated with the UK forum which usually means things are going well with my father`s, (now solely mine as he died last year at the ripe old age of 98!), 1979 Beta Coupe 2.0L. Well not quite...
The entire brake system of the car was overhauled professionally in April 2024, (new master cylinder, flexible brake hoses, brake compensation valve, adjuster rod bushes, hand brake cable, reconditioned calipers front and rear plus new pads and re-skimmed rotors).
Caliper overhaul work was sub-contracted out and done by a local Adelaide, (South Australia) based, specialist brake component supplier and repairer, (Power Brakes). They have been in business for 60 years and have a very good reputation throughout Australia for their brake component refurbishment work. They told me they have done quite a few Beta brake caliper overhauls over the years. I supplied the front and rear brake service kits including new front main pistons, (stainless steel ones from Mark W), and rear pistons.
https://www.powerbrakes.com.au/shop/beta/lancia/vehicles%20h-p/page/shop/browse
Upon collection of the reconditioned calipers, I was informed that one rear caliper had a broken thrust clutch which was replaced during reassembly with a second hand one from Power Brakes stock of spare parts.
The hand brake was not holding on anything more than the most gentle of slopes before the refurbishment work, (which I had attributed to a stretched handbrake cable that had run out of adjustment), and even after all the brake work was completed the handbrake was still not holding on a slope!
I took the car back a while ago to the workshop who carried out the brake overhaul work on the car and had the new handbrake cable adjusted in case it had stretched a bit after initial use. It made little difference and the car still does not hold on any slope using the handbrake.
There are no symptoms of the rear brake caliper dragging on the rotor but presumably the handbrake mechanism on one rear caliper is not engaging properly. Which makes me wonder whether the second hand thrust clutch fitted to replace the broken one on one of the rear calipers is itself broken or perhaps the thrust clutch in the other rear caliper is now broken?
I have had a look at the Haynes manual and there are other handbrake adjusting mechanism components in the rear caliper which I suppose might also potentially be problematic: adjuster spring, (is that the same as the "thrust clutch"?), clearance self-adjuster, bearing which supports the clearance self-adjusting rod, thrust washer etc.
I confess I tend to glaze over when looking at sectional view drawings. I think I might be sectional view drawing dyslexic!
I did read somewhere that if the handbrake mechanism is over tensioned the self-adjusting mechanism won`t work. Here is the Google AI response to my query about the handbrake not working after a rear caliper overhaul:
"A Lancia Beta handbrake that fails to hold after a rear caliper refurbishment is a common issue, usually caused by improper adjustment of the self-adjusting mechanism during reassembly or trapped air in the hydraulic system. The handbrake mechanism in the Girling rear calipers requires a specific, manual setup to activate the auto-adjuster."
Here is a troubleshooting guide based on typical Lancia Beta/Girling caliper issues:
1. The "Knack" - Initial Setup (Most Likely Cause)
If the handbrake cables were attached before the pads were properly seated, the self-adjusters will not work.
Procedure: Remove the handbrake cables from the calipers.
Bleed: Bleed the brakes thoroughly.
Pump: With the engine off, pump the brake pedal hard 5–10 times. This forces the piston out and sets the internal auto-adjuster.
Check: Ensure the lever on the caliper rests against its stopper.
Reattach: Reattach the handbrake cables and adjust the tension in the cabin.
2. Check the Caliper Lever
Sticking Lever: The handbrake lever mechanism on the caliper body is prone to seizing, preventing full movement. Ensure the levers on the caliper are not stuck and return fully to the stop when the handbrake is released.
Internal Helix Gear: The internal mechanism relies on a helix gear. If the piston was pushed in without being rotated, or if it was not properly rebuilt, this mechanism may not function.
3. Adjuster Setting (Caliper & Cable)
Caliper Adjustment: The handbrake levers must touch their stops on the calipers when released. If they do not, you must allow the cable to be fully loose, pump the brakes, and let them return to the stop.
Cable Adjustment: Ensure there is no slack in the cables. Adjust the nut inside the car (under the center console/gear lever cover) until the lever pulls up about 4–7 clicks.
4. Check for Cable/Pad Issues
Seized Cables: Even with a rebuilt caliper, the handbrake cables themselves might be seized or stiff, not allowing enough force to be applied.
Wrong Pad Installation: If the pads are installed incorrectly, specifically if the rear pads (which have nubs to catch the caliper piston) are not properly aligned, the handbrake will not function.
Summary Action Plan
Disconnect cables at the rear calipers.
Pump brake pedal (hydraulic) 10 times.
Check if caliper lever returns to its stop.
Reconnect cables, remove all slack in the cockpit.
Test on a steep incline.
If the handbrake still does not hold, the internal helical gear mechanism within the caliper may not have been correctly reassembled during the refurbishment."
Hard to believe the workshop who did the brake work did not get the initial brake system reassembly and adjustment right. The owner has been in business for 30+ years and his mechanics are competent. The same mechanic always works on my car...his two uncles were both Fiat factory trained mechanics in Italy who were recruited to Australia by a local Fiat dealer back in the 1970`s!
I assume that one of the rear calipers has a sticking handbrake engagement/adjustment mechanism and possibly another broken "thrust clutch"? Which made me wonder whether anyone might have some rear caliper handbrake mechanism spare parts in case Power Brakes have nothing suitable on the shelf to repair it again.
The local workshop did suggest trying to engage and release the handbrake a number of times to try to free it, when I mentioned the problem whilst I was there getting work done on a different car, ironically my old Mazda 626 GD also with rear brake caliper problems...a failed handbrake mechanism dragging on the rear rotor no less!
Any thoughts, suggestions or offers of rear caliper handbrake mechanism parts much appreciated!
I had not followed up the problem diligently as the car is a hobby car only used a few times a month, (typically fortnightly), and one can live with a dodgy handbrake, even if hill starts are a bit of a challenge. On the one hand I was fed up with the amount of money spent on the brakes only to find the handbrake holding no better than before, (the calipers were starting to bind which necessitated the overhaul in the first place).
So I thought I would just put up with it rather than take one or both calipers off again and have them, stripped down and inspected again for damaged or broken hand brake mechanism internals. On the other hand it seems crazy to spend all the money on a complete brake system overhaul and not have the handbrake work as it should.
By the way, I have seen new Italian made Fiat rear brake calipers with 34mm and 38mm diameter piston sizes for sale in the UK but not 36mm diameter Beta ones unfortunately! Shame you can`t just buy and fit all new rear calipers!
Cheers,
Andrew
PS Message to moderator: I could not undo italics from "Hard to believe the workshop..."! Italicised text only show up after posting and I could not work out how to edit some of it back to normal unitalicised text.
peteracs:
Hi Andrew
First on the Italics, if you go to modify the post you will see i enclosed with a pair of [] which is the start of the italics section, then to finish it you use the companion /i which is also enclosed by [].
I have modified it for you, but you may wish to change it to suit.
Secondly, yes I have a few parts from rear calipers you are welcome to.
Peter
JASPER_40:
Just for reference,
These are the components of the rear caliper, including the adjuster mechanism within the piston itself.
Just re-built my 2 rear calipers and a couple of spare calipers I had aquired. Happened to have 2 piston / seal kits in my cupboard of accumulated spares to do all 4 (there was nothing much on the TV !!)
Cheers,
Steve
Nigel:
A common problem 40 years ago was the tag on the self-adjust spring
would break. The immediate effect is the failure to self-adjust. The mechanism
then struggles to keep up with pad wear, the handbrake lever starts to rise, and
eventually doesn't hold the car.
There is no method to manually wind the screw, that tag is critical to the operation.
As it's buried deep inside, it's possible it wasn't checked on your rebuild.
And, as you've got new pads, bedding in would have increased the lever action
required to actuate the pads.
I suggest you look at the position of the levers (where the cables join).
They should only be moving around 5/6mm from a fully rest position to when
the pads bite. I suspect that your levers are already far into their travel when the
handbrake lever is fully off. (i.e. the handbrake cables have been adjusted up to attempt
compensating for the lack of self-adjustment)
Not simple to describe, but I hope you get the point.
Nigel
Gromit:
Nigel,
Your description probably identifies precisely what transpired over the years and would explain the mediocre handbrake holding performance of the Beta Coupe PRIOR to the caliper rebuild ie a broken self-adjusting spring in one rear caliper.
I dug out the damaged and replaced original "thrust clutch" which Power Brakes removed and replaced from one of the calipers when they did the caliper rebuild in 2024 and it is exactly as you described: no protruding tag or right angle extension of the spring beyond the end of the clearance self-adjuster. It had snapped off clean at the point where the spring is still wrapped around the cylindrical body of the clearance adjuster barrel.
Just to be clear to everyone, the broken part in question to which Power Brakes refers to as a "thrust clutch" is the combination clearance adjuster with the self-adjuster spring wound around it, part # 3 and 4 in the sectional view drawing of the rear caliper and piston fig 9.3 of the Haynes Lancia Beta service manual, page 149. It is the part immediately to the right of the piston in the very helpful photo provided by Steve (Jasper_40) in the previous post.
So if the clearance self-adjuster with broken self-adjusting spring, (aka "thrust clutch"), WAS replaced on one caliper during rebuild and presumably the other one was found to be OK, did the other caliper self-adjusting spring break after reassembly of the brake system? Would that explain the current problem?
In which case it looks as if I might need at least one more replacement rear caliper "thrust clutch" or combination clearance self adjuster with an intact and undamaged (protruding tag or spring end not broken off), self-adjusting spring.
Peter, do you have any spare rear caliper clearance self adjusters with intact (unbroken) springs in your spares collection you might be willing to part with?
Andrew
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