I only got to the 6;25 mark , when he shows you his cleaned pieces , you can see the real shiny surface of the edge of the sleeve ,lying right next to the darker cast "outer edge " of the bored hole.

Just a thing with his cleaning , he never mentioned cleaning out the drilled holes between the bores , or taking out all the fittings and blasting cleaner and compressed air up them to clear out any crud .

 

Noted, thanks.

I guess I'll find out if I pull mine apart.

 

Bleeding brakes using the brake pedal method works just fine. I've never done it any other way in over 40 years and it still works. But its your money to try other methods but the results won't be any better.

 

here you go..here are multiple ideas. If you have a piece of steel or aluminum lying about you can make one today since those garden sprayers are quite common at the local hardware stores:

https://www.corvetteforum.com/forums...y-version.html.

It works so well that I just use it whenever I do brakes on any of my other cars too.

 

I don't know how cheap you want to be. The full kit is $80- (dunno how much shipping will be), and the Motive GM MC attachment is $40-.

You can certainly fab your own pressure tank, but the cap is pretty nice. Throw the chains away, and use a clamp, like this. If you have a thick piece of Lexan, you can make your own, and, with a creatively cut gasket, see what's going on inside the MC.

 

The pressure pump is probably the most economical and quickest solution.

I have an electric pressure/vacuum bleeding machine. It's pressure/fill at the m/c cap and and simultaneous vacuum at the bleeder (the old fluid goes back to a catch container). Personally, I prefer skipping the pressure portion and just use the vacuum motor (pump) for drawing old brake fluid out. It's not under a lot of vacuum, it's slightly slower but more controlled. I think I tested it and it was like 12" or maybe 10" mercury vacuum. It works great that way. I've been using it that way for years. Then you don't have to screw with the pressure cap. A guy could make such a system really easy with a 12 ebay self-priming vacuum pump that can handle fluids. The one little tip is, put a drop of gear lube on the caliper bleeder screw threads. The vacuum will draw the lube in and create a seal (won't suck air) and it goes faster. If you have an A/C vacuum pump you could do the same thing ...except put a catch-can before the pump. Only issue with an AC pump is they produce too much vacuum. but I know guys who've done it. You get a lot of fluid fast ..lol.

Something along the lines of this:

 

Thanks all.

The bleeding factor is one I'll consider, however with a firm pedal both before and after my bleeding exercise and the pulling factor existing before and after the bleeding exercise, I'm not 100% convinced this is the root cause of the pulling. If it began to pull after the bleeding, then yeah, smoking gun, but with it not being impacted before or after bleeding, I'm less inclined to look here first.

I suspect seeking mechanical gremlins at the calliper regarding pad, piston and blockage might be the first place to start?

 

Disconnect a brake line at the caliper and press the brake pedal. Fluid should readily squirt. If not, there is a problem upstream. Reconnect and do the same at another caliper and so on. The squirts should all be of equal force. If they are, remove a suspect caliper and press on each piston for freedom of movement. All 4 pistons should react the same. If not, separate the two halves of the caliper for further inspection of the bores.

 

I agree. It is not the bleeding. It pulls to the right. The newer calipers are on the right. Seems obvious.

 

Yer best bet is to (IMO), not overthink it, remove the caliper, (shove a piece of cone-shaped rubber in the end of the brake hose, or a brass cap, to prevent brake fluid from dripping out while you work on the caliper). Then disassemble your caliper in question. It only takes a few minutes. Like I said before, tap under the dust seal with a dull gasket scraper (putty knife), to remove it w/o damage, then pull out the piston/s. See what you have. What the bores look like inside. For sure, even with SS there will be some scoring(that's normal). Don't let a little scoring dissuade you from re-doing the caliper. You can make a DIY hone out of a piece of undersized PVC (pipe cap) on a bolt (arbor) ...and some foam between a piece of 600#. The foam holds the sandpaper tight to the bore ..a little wd40 to lubricate as you spin the assembly (diy hone) with a drill. This actually works better than a 3-stone hone imo because most hones are like 180 or 220 grit, some up to 400#. I would go 600# myself, or even slightly higher (that's what I do). I take pistons apart on many vehicles I work on ...if there's a brake question. Sometimes you find a lot of crystalized crud in caliper bores, but everything is otherwise more-or-less in good condition and can be put back together with the same parts or new depending on the circumstance.

On your Vette, you can knock any corrosion off the pistons and reuse all the same dust seals and piston seals to reassemble, at least temporarily to test. More than likely you'll find corroded pistons or another issue and you'll just want to go to OReilly's and get a rebuilt caliper (quality rebuilds with ss sleeves). And they have a lifetime warranty. And they store your purchase info on their computer so you don't have to save the receipt forever. The warranty claims I've had were no-questions asked. And no shipping either.

I would also check run-out on your rotors with a dial indicator. You really want .002" or less. Otherwise the rotors will oscillate the pistons and pump air into the calipers ...leading to bad things. My front ones I got down to .0005" run-out which I'm happy with.

Let us know how things turn out.

 

Thanks, will do.

Sadly, in the UK we don't have O'Riley's and most American car parts are subject to poor enhance rate, shipping, import duty, tax, mark up, then UK shipping, making them eye waveringly expensive, otherwise I'd have just bitten the bullet and put a full set of new callipers on from the get go, but over here, that'd be equivalent to over $1,000 USD

I'll strip and investigate.

 

Whoops, I didn't notice you were across the pond. That would be a long boat-ride to OReilly's then, wouldn't it? Then definitely disassemble the caliper and see what you have going on. If you don't have an air or electric impact gun, crack the large caliper bolts before you remove the caliper from the car (just break them 'free' on the car).

These calipers are easy to field-service w/o pro-tools. They're very simple, not voodoo. You can make your own DIY hone or even hone by finger (and sandpaper). The one area to take note is the 0-ring seat. My recommendation would be to cut a piece of 120 grit or 180# wet/dry sandpaper the size of the bore the O-ring sits into ...and it's mating area ~9mm, I'm guessing. Glue that 'dot' of sandpaper onto the end of a wood dowel and stick it in a med-speed drill (uses WD40 as your machinging fluid). Clean the seating areas on both caliper halves so they look nice. The idea being that the o-ring is an common leak point ...so you want to pro-actively produce a 'machined' seat for the o-ring to seal against and avoid leaks if you can. Truth be told, a lot of 'pro' rebuilders do a horse-crap job machining that area and the tiniest corrosion eventually causes an o-ring leak. A good machined seat will help you out. And clean/hone the bores like I suggested in the post above ..or just use your fingers. Clean off the pistons with sandpaper if they are really corroded ...so they move freely in the bores. Ideally you don't want to remove the anodized coating, but we're talking worst-case and temporary use here ...and you can get the car on the road and order new pistons/parts if you need (maybe the whole caliper is toast??).

That should get you going and back on the road for now. And if you need to buy a re-built caliper, you can do so at a more measured pace, or maybe you'll find decent ones at a local swap meet or the internet. Let us know when you get them apart what you find.

 

Right, the update you've all been waiting for!

Got the wheel off and took a pic of the recent rotor and hose...




Assuming pads were done at the same time, as they are full thickness...





Neither pad were a 'rattling good fit', but both were able to move to a degree, one more than the other. One came out with a bit of a wiggle and pull, the other needed a screw driver to lever it out, at which point I noticed the pad material was not fully bonded to the backing pate. Whether this failure was cause by my wiggling and levering or due to poor manufacture that was already an issue is inconclusive. What is conclusive is I now need a new set of front pads...





The pistons did move all the way in and out, albeit one side felt a little more 'sticky' and 'grabby' than the other. What I did observe whilst pressing them in and out was a slight bubbling / hiss noise, accompanied with a weep and bubbling at the edge of the dust shields which I assume is not 'within tolerance'?




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I've no frame of reference for whether these pistons and bores are good, bad, normal or whatever so will await feedback from those more experienced with these callipers than me...






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My own observations so far which I'd appreciate confirmation of (or otherwise) - I have lip seals and some / all of the bores need a hone. The callipers appear to already have been rebuilt with stainless inserts?

Given the above, what next?

I just hope this hasn't been boring for you?

 

great pics..
if me.. i am taking brake fluid and some 2000 grit and cleaning up the bores. and putting in new pistons and O Rings..

and agree as above if those generics are off the rotor high.. replace them ..

 

I would say with all that crap in the pistons and the shape of the pads,,, they were shot. The disc looks like the pads weren't pressing on them. It does look like they can be rebuilt. The pistons look corroded, if they are, replace them also.

 

So it is fair to say we have likely found the cause of the pulling?

Also, they are stainless inserts, right?

I'll see if the passenger side generic is riding high, and if so, replace, although the job will be to find a Delco casting for sensible money.

The cost of this stuff over hear is circa $300-£325 per corner, making Wilwoods not a great deal more....

EDIT: By asking of the generics are off rotor high, are you questioning whether they seat the pad correctly over the full face of rotor?

 

Yes, those are stainless inserts, at least in that caliper. I'd order a set of CSSB Inc. High-heat O-Ring caliper rebuild kits (with pistons), and see if that works for you. Or jump to Wilwoods, which might take longer and cost a LOT more.

Don't forget to buy all new, matching, brake pads.

 

CSSB inc?

Limited by choice in the UK.

This is what we have, at about $120... https://www.corvettekingdom.co.uk/pa...ion-front/8293

 

If I decide to get new callipers and import them myself, where is the best place to get new Delco casting, O ring items?

 

Those might work. I know the CSSB Inc. ones work. Unless they moved, they'll ship from near Miami.

For my other car, I bought mine from Zip when they were on sale. They were specifically original Delco Moraine castings, rebuilt by Lonestar with O-rings. Perhaps you can find a better deal that checks all of the boxes.