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Sorted the front bearing noise, it wasn't that at all, I dissasembled the brakes only to find....

The left rotor's inboard pad was worn 0.5mm and the outboard pad was 13mm! The noise was the worn pad warning screechers going off and not the bearings! I replaced the front left CV a year or less ago so something must've gone wrong then during re-assembly.

The right side brake rotor's pads have equally around 13mm as well so that is working fine. The car still brakes in a straight line.

I assumed that the caliper was getting stuck on the guide pins, so I cleaned and lubed it and the right side too.

Took it for a test drive, it braked straight but the brake pedal was way too spongy and was dropping to the floor. Bleed the brakes again. Same problem was still there.

Tested the brake servo all is OK. Hard pressure with engine off and drops when engine is started.

Observing the caliper movement, the left caliper moves around 5mm-10mm when the brake is applied and locks the rotor, right side moves less than a poofteenth almost undetectable by feel but locks the rotor so I assume working OK. Handbrake applied and locks front rotors.

So these are my thoughts with the left side caliper but could be wrong;

1) the piston is retracting too much back into the bore which shows in the caliper having too much movement in travel

2) therefore to make up for the extra distance the feel at the brake pedal is spongy, correct?

3) although there are no external leaks I will need to rebuild the caliper due to an internal seal failing?

Is this the real problem or a guide problem?

Rebuild kits are $22 without the piston, no problem as I've done quite a few calipers from different vehicles but any tricks with the dissasembly? I have never dissasembled a caliper with a built-in handbrake function and believe that there is a trick to it and can be done without special tools?

Another thing, could I have damaged something when I used a brake piston spreader (screw type) to push the caliper in to fit new pads instead of turning it clockwise, *as the book* instructs, with a special tool (1/2" modified socket with matching tangs)? I've always used the spreader without any problems with other cars.

Any tips and ideas would be appreciated and thanks in advance.

I would be checking the rear brakes as the slaves in the drums have a tendancy to leak profusely which would be more of a cause for a spongy pedal than the calipers at the front

and the right front caliper may be siezed this is caused by the handbrake assembly being over extended as the brakes have worn so the brake is now neither on or off

TOONGA

But the rears are not leaking as I just bled them and the rims etc. are dry. The rear right drum came off 2 months ago too when I fitted the rear bearing and it was dry, the front disk inner pad would have already been wearing by then. I'll have a look at it any way tomorrow. Thanks.

The HHV also has a mind if its own and works occasionally, would this contribute to any problem? I know it is not linked to the left caliper but what do I know?

I thought it was likely that if you have dry or worn sliders you will get uneven pad wear. I think I need to do my Brumby front calipers as an overhaul, after 26 years surely can't hurt. Those handbrake jiggers anre a mental stumblng block for me too, but others have coped....

Rebuild your L/H caliper, or if you are not confident then take it to a brake place! The excess movement of 5-10 millimetres is where your spongy brake pedal is coming from.
You may well have busted the screw mechanism inside the piston that makes the handbrake work when you pushed the piston straight in instead of winding it in, like the book says! If you knew this already, why didnt you do it the way the book says to do it? The calipers are different to any other front calipers you will see because the handbrake is on the front wheels, I cant think of another car that has this feature, so unless you know what you are doing take it to a brake place!
Oh, the only thing that pulls a pad back from the rotor is the twisting effect of the square section oring on the piston, and this combined with any wheel bearing play will give the rotor clearance from the pad, usually only enough for the rotor to turn and the pad to drag very lightly, this is why the pedal sinks with all that freeplay!

Also, you can get away with using a pair of flat or duck billed pliers to wind the piston in our out, just put the tangs of the pliers in the notches of the piston and jam a screwdriver in the pliers to supply yourself with a lever to turn the pliers. If you cant fix it, go to the wreckers and grab another caliper and put a seal kit into that.

Busdriver wrote:Also, you can get away with using a pair of flat or duck billed pliers to wind the piston in our out,

After realising that things were not going as smoothly as I hoped, piston was stubborn in moving into the bore, I referred to the book, and all was revealed. I'm hoping that with the use of the spreader, that was spinning the piston clockwise anyway but under pressure, might have saved some damage. But I'll know when I get them apart. A good sign is that the handbrake still works the piston on on-road testing!

Just like my 30 year old Moto Guzzi motorcycle Subarus are indeed just as "quirky". This makes them that little bit special I reckon. Yes I do tend to learn the hard way but at the end I know the vehicle intimately and that's a good thing!

I refuse to give anything to a mechanic, there's no fun in that and you don't learn anything. Perseverance wins at the end of the day and there's the pride in knowing that you've done it yourself even if it took you all day for a 2 hour job. But that's why forums exist right, I mustn't be the only bastard out here who give things a go and needs tips?

Speaking of tips, I did end up using the nose of a pair of stub nose pliers which were much better than the easier reaching long nose, but they were jumping off the edges of the cutouts in the piston. Maintaining even pressure on two points was awkward when you have two wide apart handles to balance. But your tip using a screwdriver across the handles is a good idea. However, I have since found a worn out socket that I will modify for the purpose, it should now be a doddle.

My home made "special" tool collection is buiding up!

Thanks for the feedback.

Special tools are a requirement in everyones toolbox. Good to hear your collection is building up. Sorry, didnt realize you had a old Guzzi as well, now I understand your penchant for doing it yourself a bit better, if you took that into a shop you might never get it back! Kidding! I reread my reply and thought that it may have sounded a bit harsh, sorry, but brakes are something that dont just affect the car that has the faulty ones and as I used to be in that trade I got a bit frustrated at times with some of the things that people used to do to try and fix them. Do attempt to O/haul and all the best with it.

Busdriver wrote:Special tools are a requirement in everyones toolbox. Good to hear your collection is building up. Sorry, didnt realize you had a old Guzzi as well, now I understand your penchant for doing it yourself a bit better, if you took that into a shop you might never get it back! Kidding! I reread my reply and thought that it may have sounded a bit harsh, sorry, but brakes are something that dont just affect the car that has the faulty ones and as I used to be in that trade I got a bit frustrated at times with some of the things that people used to do to try and fix them. Do attempt to O/haul and all the best with it.

Hehe, it's true, non-Guzzi workshops get stumped all the time. Following things by the book sometimes is just not enough. Knowing that poking your tongue out to the left is all that is needed to make things work! Guzzis seem to do that to their owners. That's why lots of people keep 'em forever, they become more than a motorbike. And it seems Subies are doing the same thing to hands-on owners that I've noticed on this forum. People wonder why you would own a 20-30+ year old vehicle...if they ask they don't understand. Sadly some people lack *passion*.

I have responsibility of 3 family cars, I run a database for them, yes a bit annal but it helps me determine if certain things have retired before their due date. This info then determines if other thing could be causing the problem. With this d'base I've worked out that it costs us $33-$45 per year in part's for each car, not including consumables. That's cheap motoring and proof that if you do things yourself you have more money for beer. Not to mention the invaluable things that you've learnt along the way.

However, at times I do need the services of "real" mechanics but usually if there is any machining that needs to be done or pooter related stuff....gear I just don't have or unable to make.

I'll sort these brakes out. I have to son get's his P's tomorrow!

Im all for more funds for beer, good on you for having a go, but please be aware that sometimes there are "real" mechanics on here freely dispensing advice from years of experience..............not all of us are out to rip everyone of, although that can be a bit hard to swallow sometimes.

New seals solved the problem, the old piston seal had a fine raised seam worn around its centre perimeter. Both caliper's slides have been lubed and both working the same, that is bugger all caliper movement when brakes applied. So all is good. But....

I have been unable to attend to the rear brakes as I feel the problem with the spongy brakes (still) might be coming from there as someone suggested. Otherwise the problem would have to stem from the master cylinder?

However, according to elder son who drove it for 2 years says the brakes feel normal...hmmm must explain a few things to these boys me thinks.