Bongo Fury

Peeps, need some advice please
Took the old girl for its MOT today, and it failed on not enough movement on the nearside front wheel. Basically, the guy said strip it down, clean it out and it should be ok. Its like the Brake is on all the time, and the calliper is very tight on the disc. Anyway, stripped it down and couldn't find much wrong, but can't for the life of me get the pistons to go any further back. Below is a picture, I noticed that the rubber bit has come away a little, is this right?
Do i need a new calliper or perceiver with trying to push them back.
And where would I get one from if needed?


Cheers peeps

I had a new one fitted last week.

A seal kit is about £30 on Ebay or a whole new (remanufactured) caliper is £48 (ex VAT) plus you get a rebate on sending the old one back.

If you can't free it by working it and you're considering striping and cleaning imo it would be better all round to simply replace it.

Supplier and part numbers here
http://www.igmaynard.co.uk/bongo/forum/ ... =3&t=47100

hth

To free the pistons up, you need to take the pads out, then find something to wedge against the brake disc that's about the same width as the metal backing on the brake pad. Then gently step on the brake pedal. The pistons should now be out against your wedge, and at this point you can wipe brake fluid onto them, then lever them back in. Repeat this process a few times. It should free them up enough for MOT purposes, unless they are really far gone.

My personal opinion is that it's best to get rebuilt calipers from a reputable specialist -- someone who does them every day and doesn't rebuild them on the cheap. Front brakes are pretty important...

Hi dext924,

As the mechanic said clean it out,if you put some rubber grease on the pistons then work them back and forward they should ease off.You will need to get a flat lever between the disk and pistons and lever them flush,then press the brake.Keep repeating this until free,its quite a simple operation.

Cheers Mal..

Thanks for the info.
As you can see from the photo, it looks as though a seal has gone, and I am not sure if it will go back in or not. I am afraid I am a bit of a novice when mechanics is the game, and my tool kit is not the most extensive! Will this seal go back in do you think?

I think for the extra few quid, a refurb one might be better than me trying to strip down the thing to replace all the seals, and if you get a few quid back, then thats no so bad I will give it another go in the morning see if I can work it loose a bot and get the seal to pop back in, as its not damaged or anything

So, not quite a clean pass for my first MOT but I suppose it could have ben so much worse.........

nfn wrote:My personal opinion is that it's best to get rebuilt calipers from a reputable specialist -- someone who does them every day and doesn't rebuild them on the cheap. Front brakes are pretty important...

Couldn't agree more, like the one I got

dext924 wrote:Thanks for the info.
As you can see from the photo, it looks as though a seal has gone, and I am not sure if it will go back in or not. I am afraid I am a bit of a novice when mechanics is the game, and my tool kit is not the most extensive! Will this seal go back in do you think?

I think for the extra few quid, a refurb one might be better than me trying to strip down the thing to replace all the seals, and if you get a few quid back, then thats no so bad I will give it another go in the morning see if I can work it loose a bot and get the seal to pop back in, as its not damaged or anything

So, not quite a clean pass for my first MOT but I suppose it could have ben so much worse.........

Hi the seal is OK,what you see is a dust cover as such,if you dont feel comfortable doing these type of jobs I would recommend that you take it to a garage.At the end of the day its your life and others.

Cheers..

Hiya
I'm a newbie / long time lurker here but I've rebuilt a lot of calipers (Nissin and Brembo) in my time.
In the photo the dust seal only is dislodged not the seal. I'd say not the culprit here.
The reason the calipers bind is usually that corrosion occurs under the seals in the rebate in the cylinder itself.
This gets progressively worse, binding the seal tighter and tighter on the piston until it won't move.
The only sure way to loosen it off is to strip the seals out and scrape out all the white oxide you'll find in the cylinder rebate.
Greasing up the piston might get you through an MOT but that corrosion will remain until you do a strip down.
The only other binding place is on those locating dowels under the rubber gaiters, but this is more rare.

2000 4x4 JAL side, mushroomer, by the way

I am happy having a go at it, as I have done this job on by bike before, its just awkward to get to. I am trying to do it so I didn't take the caliper off the hose, to save bleeding the brakes, but I can see this is going to have to be done it think, especially if I need to strip it down. I thought if it was just a case of putting the piston back in, then I would be ok, but its being a bit if a bugger!

Chris, sending you a PM

I wondered what I was going to do on my day off tomorrow.....

Here's a bit more info about my caliper replacement in jack's thread on the same subject.
http://www.igmaynard.co.uk/bongo/forum/ ... =3&t=47150

The caliper comes ready to fit with new pistons, seals and gaters.

I got the garage to fit mine because I don't have anywhere to work.

When I have had to do this on my motorcycle, I have been advised to take the top off (or at least loosen it) of the brake fluid resevoir. If you haven't done this it might explain why it is so difficult to get thrm back in.
ian G

Leaving the bleed nipple loose will be ok as they will be drained anyway. Cap off is for new pads in existing undrained system.
I use a small piece of wood (or old brake pad) across both pistons and one of those cheap pump action G clamps from B&Q to ease them back in.

So, after following advice, (thanks to all) we managed to sort the caliper out. Didn't have to strip it down, just work it free with a bit of brake fluid down the sides and clearing the gunge out. End result, caliper works fine.
So, back to the testing station, to find out it now needs the other side doing. After hitting the roof as to why they never told me in the first place, he explained that the off side never failed in the first place, but the near side has been cleaned properly, it has caused an imbalance in the front brakes, so the off side needs doing as well!!! What made my blood boils was when he said that 'we are not here to give you advice and tell you what to do'! Not allowed to put on the forum as to what I said....
I suppose common sense should have jumped in, but he said the offside was good and just do the nearside.
So, it back under the wheel arch again tomorrow!!!

I shouldn't complain as everyone has said that for a vehicle for 14 yrs old, they expected more wrong, I am just annoyed with the way the garage has dealt with this.

3rd time lucky