Technical Drum Locating Studs...

[mishnish]

Hi all!

Recently my Punto was in for the warranty brake recall... fair doos, 350 quids worth of work I didnt have to pay for! Recently though, I had the brake warning light come on intermittently when driving, so I had a look around and found a leak from the union on the rear drivers side brake cylinder. I set about sorting the problem by getting the right union nut spanner and a bleed kit... so it was off with the wheel, off with the bleed nipple, off with the union, blasted everything with brake cleaner to get rid of any dirt that might have been preventing a good connection, dialed it all back up and bled the system... feels great now and no leaks. All well and good you say?

Not quite... the leaking hydraulic fluid I think must have contaminated the brake shoes on that side as I get a grinding kind of noise coming from that side under braking. While I had the wheel off I tried to remove the drum to have a look see, but I was slightly bamboozled by size of spanner to use on the drum locating studs... In the Haynes manual theres a pic of a dude removing them with a 12mm spanner... lies!!! Mine wasn't 12mm!! or 11, or 13! Either mine are different (imperial or some such), My el cheapo set of sockets are total garbage, or I am in fact a total dork!

Whats my way forward? Can anyone say for sure what size they are and ill go and buy a decent socket? Would a decent adjustable spanner do the trick or is that likely to round it? If I do round it and have to resort to crazy means to get the things out where can I get new ones!!!

Any and all help appreciated from you fiat folk!
Chris

 

[custard]

they are 12mm.probably been rounded.
mole grips my friend,mole grips.

 

[mishnish]

Mole grips aquired... from ASDA no less, at a fair penny... draper value for £3.50 - also picked up a couple of wire brushes at 70p and some gash drivers - 50p ish for chewing up on stuff.. Im sure they will come in useful, and I was only going out for bread! Will let you know how it goes tomorrow... as I say before tho... if I do knacker the locating studs, whats the route to replacement?

 

[dave]

you can leave them off if you like

 

[mishnish]

right enough... the wheel bolts are doing all the work of holding wheel and drum to hub... the studs wouldnt have to be done up tight or could even be left off... that gives me options... they dont come in the rear brake pad fitting kit do they? I have a rear axles worth on order....

 

[mishnish]

Right!

After a ferocious battle, the locating studs lost their grip on the hub... the drum duly came off for my little inspection and I was slightly shocked by the nastiness thus revealed...

What I could gather is that its fairly rusty in there, so I scraped and wire brushed most of it off in anticipation of my new shoes and cylinders arriving soon. I thourougly cleaned the area with brake solvent and wire brushed the glaze off the friction material. I reckon the scraping noise under braking could be due to the leading shoe missing its little spring retainer that keeps it held down... I will test drive it shortly to see if theres any difference.

One thing to note is that I found "Lockheed" on the shoes. Does this mean that my cylinders are Lockheed too as opposed to Bendix?

As a total beginner this little excersize was really me just convincing myself I was up to the job... seems like if you take your time, think about it and use the right tools you can do a hell of a lot. This will probably be hundreds I dont have to spend at a garage!

 

[sps]

Right!

After a ferocious battle, the locating studs lost their grip on the hub... the drum duly came off for my little inspection and I was slightly shocked by the nastiness thus revealed...

What I could gather is that its fairly rusty in there, so I scraped and wire brushed most of it off in anticipation of my new shoes and cylinders arriving soon. I thourougly cleaned the area with brake solvent and wire brushed the glaze off the friction material. I reckon the scraping noise under braking could be due to the leading shoe missing its little spring retainer that keeps it held down... I will test drive it shortly to see if theres any difference.

One thing to note is that I found "Lockheed" on the shoes. Does this mean that my cylinders are Lockheed too as opposed to Bendix?

As a total beginner this little excersize was really me just convincing myself I was up to the job... seems like if you take your time, think about it and use the right tools you can do a hell of a lot. This will probably be hundreds I dont have to spend at a garage!

#
the locating studs are really for locating the wheel when refitting it.

on my car i noticed that a couple were missing,so off i went to the local scrappie and was lucky to get two studs for pound and now all drums .have their locating studs.

 

[mishnish]

Result!

The grinding noise has gone and I noticed a slight improvement in the braking. I can't wait to fit up the new shoes and cylinders and see what its like... I may even push the boat out and get a new set of drums as mine seem to be rather rusty and have a slight lip on the inside edge... I know theres all sorts of dimensions in the haynes as to what inner diameter to replace them at, but in the absence of decent measuring kit is there any rules of thumb to say when the drums should be replaced? I did have a bit of a time getting the drums off due to the little lip thats formed...

 

[Hellcat]

Most drums will not be replaced in the lifetime of the car. If you do get some get them hammerited black before fitting. Then they'll always look smart!

 

[dave]

they are only £10 each from motor factors, may as well just get them

 

[mishnish]

Just an update...

New pads and wheel cylinders fitted and perfoming well While I was in there I wire brushed everything, degreased and rustkoted... I used a flappy sanding wheel to recondition the innards of the drums, and once the rust was all gone there was not much of a lip at all, so decided to recondition and hammerite black the outsides of the drums. All refitted with a very light smear of copper grease on the shoe contact surfaces, All bled, sealed and working again no probs... I have pictures of before and after and of how to set up the shoes, springs and self adjusting mechanism if anyones doing it for the first time and wants a little visual reference. I can also quote what spanner sizes and tools you will need if required! thanks for the help people, I just saved myself untold rediculous amounts of money, which will only go to replacing more stuff ;-)

Just out of curiousness... If was to have replacement pads, drums, cylinders, pads and discs, and bleed with new fluid at a garage, what would it cost me? Just curious to see what ive saved doing it myself.