Fixable?

[the_boozer]

take it off clean it up slide pins as well may as well do a brake fluid flush admit it the longway is happening weather or not a seal kit is brought when you get more brake fluid is up to you but sounds like your pulling it apart. a little rubber grease and it will push bake in on the bench while your pushing down on it easy enough . otherwise use the old pad and the gclamp set it up square enough while holding your tongue the right way and it will go back in hope you didn't get any crap in there.

 

[losh1971]

Agree with boozer, its time to fix it properly. Remove the main seal but if you can, leave the dust seal in place. The dust seal is a bastard to get back in properly if it comes out of its groove. Using a seal hook gouge out the groove the piston seal fits into. What happens is they can get rust in the groove and it makes the seal jamb on the piston.
If the piston doesn't push in with your fingers and thumb, if you have greased it or put some fluid on it, there is a reason it is jamming and it will be one of the seals jamming it.

 

[Adrian's Vr]

Agree with boozer, its time to fix it properly. Remove the main seal but if you can, leave the dust seal in place. The dust seal is a bastard to get back in properly if it comes out of its groove. Using a seal hook gouge out the groove the piston seal fits into. What happens is they can get rust in the groove and it makes the seal jamb on the piston.
If the piston doesn't push in with your fingers and thumb, if you have greased it or put some fluid on it, there is a reason it is jamming and it will be one of the seals jamming it.

Yeah so i done this and had to hammer/multi grip it in, this was super tight and its impossible to try to do it with the seal on, we tried putting the seal on afterwards but it came out straight away, the piston doesn't go back in with the brakes, either im doing it stupidly or shes rooted. Got a extended roady date Tommorrow so may need to wake up early and get a wreakers brake

 

[losh1971]

I think this will be your best bet getting a used caliper and bolting it on. If you grease the piston and have cleaned out the grooves and have the seals seated properly they push in with your thumb. They only jamb if the seals are not seated properly or you haven't greased the seals. But like I said the dust seal on the stock VR brakes are an absolute bastard, due to design of the housing. The dust seals get hung up on the top edge of the housing, right where you have a nightmare getting the seal to push in, due to a lack of space.

 

[vs-lover]

The photo you initially put up shows that the piston will not go back as you have the dust seal doubled over and jamming the piston and seal together.

The way I've always done it is to pull the piston right out and then remove the dust seal as well.

From there I will slide the dust seal over the end of the piston and wriggle the seal up the piston about halfway so that the leading edge of the seal is able to be slipped into the retaining groove of the calliper. Then slowly offer the piston into the opening that's hidden by the dust seal until you feel it's up against the fluid seal squarely.

Now squarely push it in using both thumbs, one on each side and push firmly. Once you can feel its moving squarely in about half way then slide what's left of the back end of the dust seal backwards into it's groove.

Finally squeeze the piston fully home and you're good to go. Don't forget to bleed the system.

 

[losh1971]

I rebuilt my calipers and tried the way you said VS lover and I couldn't get it in. I had to fit the dust seal then push the piston in. I found it an absolute mongrel to get the seal to seat right in the corner, where it has the flat. I can normally rebuild a caliper in 10 minutes but the VR ones are the trickiest i have ever found and it comes down to that damn dust boot.
What you find also is that it all looks good but then when you push the piston out with compressed air to test, the boot pops out of its groove, right in that bloody corner.

 

[vs-lover]

It's not the way you do it it's how well you enjoy doing it I always say.

Cheers.

 

[losh1971]

Yes true VS lover, rebuilding my ute calipers was enjoyable, up until the sixth time that bastard dust boot popped out of its groove, lol...

 

[stick3]

i rather work on brakes than what im doing now replacing the utes rear bushes have you got anything to clamp the brake hose so you can take the caliper off

 

[EYY]

The bleeder nipple must be opened as you'll never be able to push it in by hand against the air that's trapped behind the piston that you've had pop out. Once the piston is in full contact all around with the internal seal you've created a sealed system again, thus pushing by hand is impossible. Opening the bleeder will allow the trapped air to escape.

After this situation you will have to bleed the system to remove the air and have fluid take up all the space inside the calliper.

It'll push back in just fine, the fluid will just be returned to the res. If it hasn't broken the seal shouldn't even need to bleed it.

Although, it's a good idea to rebuild the caliper or at least clean the piston properly since it's at this stage. If you're having issues getting it back in, it's either dirty or the piston isn't being pushed in square to the bore. If you've gone past the seal, the piston can catch and damage it too if not careful.