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Discussion Starter · #1 ·
i've got the fixed the grounds and it mostly works well.

i'm pretty happy, i've never touched brakes before, other than learning about it in a text book and reading some stuff on this site, and i took off and apart the back brakes today without any problems and i think i know why they were seized, the wheel cylinders are full of some crap and the pistons won't go back in. is it possible to just clean this junk out and they'll still work or do i have to order new ones?

since i'm on a pretty tight budget for now (hopefully not for long) i'm trying to save as many expensive parts as possibly, and at the local NAPA store says new ones are $71can each :eek: ... something had to make up for the cheap rotors ($27can each) which i'm happy about

also, one of my drums has a chip out of the edge of it that goes in about a 1/2", or to about the inside edge of the backing plate, is it still safe to use it again after i get it turned or should it be replaced too?
 

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well, sometimes you can clean the crap outta the wheel cylinders, put them back together and make them work, so long as the seals are not shot. the seals are what matters, and you must be able to get the bleeders broke free, or they're worthless anyways, as you'll never get all the air out of the system. if all thats wrong with the drum is a chip, it should be fine until you can get around to replacing it, come to think of it, one on my manta is chipped, for the last 4,000 miles.
 

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New Cups

simplemind7 said:
the wheel cylinders are full of some crap and the pistons won't go back in. is it possible to just clean this junk out and they'll still work or do i have to order new ones?
Just clean the muck out and look at the inner surface to see if there are any deep rust pits in there. If they are not too bad then they can be lightly honed with a brake cylinder hone and new rubber seals ("cups") can be bought very cheaply from any autobrake supply store as most are pretty standard in each size. Opel brakes are usually ATE brand as are BMW and VW so seals of the right size should be easily available.
If the bores need to be honed more than 0.004" oversize then oversized cups are available too. The original pistons can be reused with a bore up to 0.007" oversize, as long as oversized seals are used.
HTH
 

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I thought this topic needed its own thread, so here it is...

One issue that sometimes comes up is the aluminum pistons get badly corroded. Sometimes so badly that they seize into the cylinder bore. And the pistons get almost "crumbly". I have seen kits in the past that come with seals, pistons, the internal spring and the outer rubber cap, but lately all I have found are the simple kits with the rubber parts. But as Jim says, they are a standard size (5/8", not even metric!) and a decent auto supply store might even have the complete kits. Just make sure that the cylinder bores are clean with no visible pits (the cylinder hones are available from Canuck Tire, look at the Speciality Tools section) or you might try taking them down to a brake shop and have them hone them for you.

HTH
 

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I was quoted 47 bucks US for rebuild kits locally. I went there before
I redid my rear brakes on the GT. I got them from Todd at 22 a side when OGTS was out of stock and had no delivery date. This is alot of the reason I've been looking at other options for the wagon. I wouldn't mention an option if it didn't look feasable. I have one cylinder done and the other will be easier. Honest to god I have less in an upgrade than I do in a rebuild kit for one side.
 

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Discussion Starter · #6 ·
actually, i'd like to know what happened with those too, and do you need anything else to make them work properly?
 

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nobody said:
I was quoted 47 bucks US for rebuild kits locally. I went there before
I redid my rear brakes on the GT. I got them from Todd at 22 a side when OGTS was out of stock and had no delivery date. This is alot of the reason I've been looking at other options for the wagon. I wouldn't mention an option if it didn't look feasable. I have one cylinder done and the other will be easier. Honest to god I have less in an upgrade than I do in a rebuild kit for one side.
Dave has a good point. If rebuild kits are that expensive, or if there is any question as to the condition of your old cylinders, a new or reconditioned set may be a better choice. And the advantage of bigger cylinders is nice too.

But if the original pistons are in decent condition, and the cylinder bores clean up without too much over-boring (which, by the by, can be done with a bit of fine (180 grit) carbide sandpaper CAREFULLY), and you can get a set of kits for a reasonable price (they are on eBay quite regularly for under $10), then doing your own rebuild also works.
 

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here you can get new brake cylinders as cheap as 12 euro's. and than i'm talking about 19mm not 15!. they do too in america. there is a topic on big brake cylinders. have a look, i mean they tell where to buy them.
 

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If you've found a source great and have them in hand then post a real pic. I just called them with that # and it shows as a cross and not available in the system. They crossed it to a raybestos finally and the price was 77 each. Parts America or CSK can't supply with that part #. I just tried
 

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That Beck/arnley part number is for a 5/8" stock wheel cylinder, not the 3/4". The only one avaliable was the w-13002 by Autospeciality but they went out of business. Nothing in wagner, Raybestos, or anything it seem besides the ones you can get from OGTS. Looks like "Nobody" has found the best fit by modifiying the LeMans unit to work. I am going to order a set and give it a try myself. Thanks, "Nobody" for working out the kinks. I would like to hear how they work when you get them on the car.
 

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Actually a rebuild kit isn't needed and new cylinders are so cheap. I have one more cylinder to do so taking a few pics is no problem. I Have a parts rear diff to show them installed too.
 

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Discussion Starter · #13 ·
i started trying to clean up my wheel cylinders today, and i got almost all the crap out of th ends where the pistons are, but how can i check if the rubber seal inside of the cylinder is good or not?

i can't see it very well since i couldn't find anything laying around to scrape the concave shape of it, so its still got some junk on it. i tried to push the pistons into it with my hands and they wouldn't move, should they?
 

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Brendon,

Take a big bejesus screwdriver and push those damn pistons, inner spring and cup seals out of the cylinder! The cylinder is a "straight-through"; from the centre, there is a spring, then at each end of the spring there is a 5/8: rubber cup seal, and an aluminum piston with a concave end which the push rods fit into. If you are having problem getting them out, one or both of the pistons are seized into the cylinder. Take a BIG round drift and BIGGER bejusus hammer and drive them out one end.

HTH
 

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Discussion Starter · #15 ·
kwilford said:
Take a big bejesus screwdriver and push those damn pistons
ahaha, best description ever... i'll try it out tomorrow, thanks
 
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