Modern Vespa

Unsure if I should give up and get my scooter to a shop...2012 Genuine Stella (Vespa's PX design)

Tried to replaced my brake pads myself and the pistons seized up, making it impossible to fit the brake pads on the rotor.
Solution to that, from what I read, is to bleed the brake line.

However, the bolt that holds the bleeder valve will not turn.
WD40d it, tried a socket wrench. Can't get leverage from the rotor because it no longer fits on the rotor.

Am I SOL? Really trying to save money on a "simple" repair but feel as stuck as the bolt at this point.

Alternatively, if I find a way to remove it from the other end (by the hose) could I just take this piece into a shop rather than tow my entire scooter?
Thanks

Try real penetrating oil. Seafoam deep creep, pb blaster, liquid wrench. Use a good 8mm closed end wrench. Let the oil sit over night. Pull the banjo bolt and screw it to the work bench, so you can get some leverage, or remove the brake pads and bolt it back on to the scooter.

WD40 is glorified water and it will displace water, also good for removing sticker glue.

kroil is the best or areokroil is the spray version.

Thank you both - I'm going to head to the store and get some of the good stuff today and let it sit over night - will update

When fighting something tight like that, don't use an adjustable wrench like you have in the photo. Use a correct size spanner or socket

And a six-point one, NOT a 12-point one! Once it's started to undo, by all means use a 12-point wrench while you do the bleeding, and just nip it up when finished.

If you're taking the caliper completely off, undo the bleeder almost completely and then smear grease all around the thread, then do up ready for re-assembly and bleeding. The grease will seal the threads so air doesn't get past them going the wrong way between pumps of the brake lever.

I can't do "thumbs up" because I'm so new - but thank you all for the tips! letting the bolt marinade in b'laster right now and on the hunt for a 6-point spanner....

Also to make sure: If and when I am finally able to turn this bolt, if I do it correctly brake fluid should start dribbling out, right?

And at that point, the pistons would be moveable, hopefully? thanks

A six-point socket is what you need. Get a cheapo set from HF. Six-point wrenches are extremely rare - and you don't want to use an open-ended one. Not on this recalcitrant bugger.

Yes and yes.

You say the pistons froze up. Do you mean you cannot push them back? One possibility is that there is too much brake fluid in the reservoir. Have you looked in the master cylinder and maybe siphon some fluid out from there?

Of course you still need to get a functioning bleed valve

Well, I liberally sprayed it yesterday with b'laster and let it sit overnight, went out and bought a 6-point socket today and gave it all my patience- it hasn't moved a budge.

I sprayed it again - going to let it sit overnight again

wbdvt - so the pistons are almost completely touching each other now. I think all my manipulating the brake/hose may have had something to do with that (?). It started with just one slightly out and now they have come more and more out since I've been trying to "fix" it lol

Are you saying if I siphon from the top, I might be able to push the pistons back that way? I guess I wouldn't know how to make sure I added additional fluid correctly after I drained it if the valve won't open for me to see.

Is it insane to try to remove it at the hose at the top by the headset/master cylinder?

I don't mean to trivialize your knowledge. You are trying to turn it anti-clockwise, right? It's a common mistake.

Did you try to use a c clamp to push the piston back?

Are you saying if I siphon from the top, I might be able to push the pistons back that way? I guess I wouldn't know how to make sure I added additional fluid correctly after I drained it if the valve won't open for me to see.

You open the master cylinder. 2 screws remove cover plate and rubber bellows. How old is your brake fluid?

caschnd1 good point and no worries- I am here to make sure I'm not making a mistake like that. I have been trying counter-clockwise but then I eventually tried both directions and it doesn't move either direction. Part of the issue is because it's no longer on the rotor the assembly is just kind of dangling from the brake line so I have to hold it in one hand and try the wrench with the other.

Garthhh I haven't tried a c-clamp yet, but at this point there is maybe 2-3mm between the pistons and I don't think I can fit even the lip of a C-clamp in there. It's kind of funny how each time I look at the pistons they are worse. I will def see about that again in the morning and add pics if that helps.

wbdvt Brake fluid itself shouldnt be more than 6mo old - I wasn't planning on doing anything with the fluid until changing my brake pads went awry. I opened up the master yesterday and there was fluid above the "min" line but some did spill. Would refilling the master help? Or is it emptying that helps?
Sorry for the basic questions, dealing with this part of the bike is a new experience for me.

I wanted to have fun trying to replace the pads myself but got more than I bargained for lol....Everything seems so simple on youtube.

I've even swallowed my pride and asked a stronger classmate to give it a go and he couldn't move it either.

Try again in the morning?

Clamp the whole caliper to something solid, like a workbench or tabletop, then try to turn the bolt out. You won't be strong enough to hold it in one hand and turn with the other (nobody would be). You can also try to use a soft wedge of some sort (like a rubber doorstop or wooden shim) and a hammer to force the pads apart enough to slip them back over the disc if you don't have a bench or tabletop to clamp it to.
Try a little heat on the bleeder threads, let it cool, and repeat the cycle a few times. Be careful not to start a fire.
Slip a length of pipe over the end of the wrench to give yourself more leverage.
Rusty brake calipers can be a pain. Take your time.

Surely it would be easier to reattach the caliper back onto it's mounting bracket to attempt the un-seizing? A barrier of some kind could be used to protect the area around the caliper if using direct heat in order to free the bolt.

Also, I note from the photo that the caliper has the Allen-keyed retaining pins. These will also almost certainly be hard to remove, if not impossible. I've had to completely replace two front calipers in my time which had those - even extreme heat (oxy) didn't help.

So when you've got the caliper clamped back on the bike or removed and in a vise, try to undo those. Good dealers undo them at first service, apply anti-seize to the threads and finally leave them only just snugged up, so they can be removed in future. That's for their own future benefit as much as yours.

take the pads out and remount it

I hope it can be done in that order - but I doubt it!

by taking the pads out it will give clearance to the rotor so he can use the bolts to hold it, THEN he can use a better force on the wrenches to break the bleeder free.

I've had good luck with corroded fasteners to nudge it clockwise (tighten) a smidgen to break the corrosion, and then anti-clockwise to remove it.

Also a farmer trick... make your own penetrating fluid with a 50/50 mix of acetone and ATF. Keep it shaken up, it separates quickly and in an air tight container as the acetone evaporates very rapidly.

But my surmise is that the retaining pins will be very difficult if not impossible to remove even IF the caliper is supported.

They will be as in the ones I have worked on I have found blue thread locker on them from the factory. So that combined with the corrosion, etc. I think you would be better off buying a new caliper. Save time and grief.

This shouldn't be seized if the fluid was changed six months ago.

Open the top of the brake fluid reservoir.
Push the pads apart, making sure reservoir doesn't overflow.
Remount calliper.
Haul appropriately on bleeder.

You do realize that loosening the bolt at the banjo will accomplish the same thing, did you try that?

Then once you get the pads pushed back and the caliper remounted so you have leverage try again with the bleed screw.

Okay updates! (with pics attached)

1) I got the bolt to turn! I used my table vise and some spare wood to create leverage and it finally moved! (pic 1) thank you thank you thank you. [[I am also aware that the way my bike is currently resting on its naked wheel is not great]]

2) I bled the brake line without issue

3) One of the pistons is much more stuck than the other. I've been slowly tapping a rubber-coated metal bar in between them to pry them apart. Seemed like the best thing I had at the time.

How it started (pic 2)
Where I am currently (pic 3)
This is what the new pads look like with the space I have created (not enough) (pic 4)

4) I decided to take a break because I don't want to damage anything out of impatience.

Advice for moving the pistons back, or keep doing what I'm doing?
(Should it be this difficult?)

Thanks again for all your thoughts and advice, you guys are awesome.

Put the old pads back in for now - this is to protect the pistons.

Get a large, long screwdriver or a pry-bar and lever those pistons back. Best done in the vice again, so more bleeding in your future.

No, it shouldn't be that difficult. Once you got the bleeder open pads should almost push back by hand. Is that scoring on the piston in pic 2? Might be time for a new caliper.

those pistons look beat to crap.

I would order a new caliper.

Lmao goddamnit - well, at least I beat the bolt!

Whether you buy a new one or repair the existing caliper, get some red rubber grease and apply a tiny amount around the sides of the pistons and put some anti-seize copper grease on the bleed valve threads.

You can disassemble and clean up those pistons, re-grease with something like Touring300 shows. The only problem I see with that plan is more corroded fasteners to remove Certainly less expensive than buying new. I looked up prices... spendy ( I can get a pair of front calipers for my Prius for less than 1/2 of what a Stella caliper costs )

that caliper looks just like a MP3 front one I have laying around.

if your interested in a used one let me know. I will measure the bolt holes and take some pics of it

a new one from SIP is priced at $100