Another Marina brake problem

[element]

I had a piston seized against the disc on the front nearside brake... managed to free it off & have been overhauling the caliper. So far I have removed one piston, cleaned it up (with brasso & 1200 w & d paper on the corrosion areas) and have put the piston back in and have replaced the seals with new ones. However when trying to do the same with the other piston (the outermost one) I can't remove it from the caliper housing.
I did the first one by pushing back both pistons with a clamp, holding the outermost one fixed with the clamp & then pushing the brake pedal to get the first piston out as much as possible. Then had to buy a puller from screwfix & modified it with the grindstone to get it to fit in the groove around the top of the piston. With 2 hand holding the jaws of the puller tightly on the piston & another two hands turning the puller to get the piston out. Have tried the same approach but can not for the life of me get this piston out... Thinking about visiting a few garages tomorrow to see if any of them have the equipment for such a job...

How did you remove your pistons? I am sure someone will have done this job before me!

[philcoyle]

Re: Another Marina brake problem

When I did my calipers some time ago I had an old land rover master cylinder that I connected to the caliper with an old flexi pipe, and then by manipulating the master cylinder I first moved one piston almost fully out and pushed it back, and then repeat for the other side until both were free enough.
Having the caliper on the bench made it easy to work on by myself. I could have achieved the same results leaving the caliper on the car and get someone to carefully press the pedal, but help isn't always around when you need it.

[stevejgreen]

Re: Another Marina brake problem

Yep, hydraulic pressure is the way to go, it acts as a penetrating oil too.
The only problem is that it's quite corrosive when it sprays around.
It may well be time to buy a new Caliper, they are common enough being used on several cars not just BL.

[element]

Re: Another Marina brake problem

I awoke this morning with the idea of refitting it to the brake pipe and clamping the one side & using the pedal to push the stuck piston out; but doing so with the caliper not mounted & instead benefiting from the flexy pipe removed from its anchor point so I can position the caliper on a few bricks etc.. this way I can apply even true pressure (as you describe) but not be restricted by the fixed feed pipe that screws into the caliper. Problem is as you say the fluid will spill all over & may even spray. If I'm prepared for that with rags & newspaper in a container I guess I'll be ok... Need to get some more dot 4 this morning first though...

[Tony Stott]

Re: Another Marina brake problem

put the caliper in a large clear(?) plastic bag taped up around the flex, the hopefully all the oil will be contained, I am about to do the same with a pair of girlings, they are both causing binding of the pads on the discs, had a look and yes corrosion on the piston ends - got new pistons, I don't think corrosion in the bores will be a great prob as the seal sits in a groove in the bore and the piston moves thro the seal!

[element]

Re: Another Marina brake problem

Thanks for the plastic bag tip - that's clever!

[element]

Re: Another Marina brake problem

Despite the plan... the piston didn't move at all. Next idea is to wrap a jubilee clip around it nice and tight & tap it with a hammer... I'm not so concerned with damaging the piston because they're pretty cheap to replace. I just need to get it out! Whereas tonight I have spent hours trawling the internet for actual replacement calipers. I found out that there's a code name of 'CA90' that equates to them & found several makes used these.. Found them on 2 sites: cheapbrakecalipers.co.uk but there's something about the site that sends my alarm bells ringing so I'm not buying there - despite their £37 price. The other site I found them on was rapidcarparts.com similar price based in Herts - 2 delivered to me up here in Scotland for £83, not bad. But atm its £8 for a piston vs £83 for 2 new calipers... I figure I'm better off changing both sides at the same time rather than further down the road have to go through it all again... One more try at the piston first methinks.

[andyf]

Re: Another Marina brake problem

I'd go for the new calipers

[philcoyle]

Re: Another Marina brake problem

What about www.bigred.co.uk I have used them before and they do a good job on remanufacturing your old calipers, even down to a choice of colour.
I even saw Mike Brewer use them on the telly.

Aren't the calipers girling type 14, used on just about every early car from fords to bmc, there could be a scrapyard near you just about heaving with suitable candidates for you to repair, a word of caution some have the hydraulic pipe enter the caliper from the rear (Triumph I think) and others from the top. A bit of thought and some pipe bending and bingo.

[andyf]

Re: Another Marina brake problem

I think so, Steve would be able to confirm. I looked with the code he posted a while ago and found some new ones for sale for about the same price as reconditioned ones...

[stevejgreen]

Re: Another Marina brake problem

No problem using BiggRed note the two g's in their name. Type 14 are very common, but check when purchasing as they are handed, and a few Calipers were manufactured with the hydraulic connection in a slightly different position. I changed my hoses to braided and did away with the short, tightly curved copper pipe.
Part numbers are available by following the link in my signature below.

[Tony Stott]

Re: Another Marina brake problem

tried the bag today, works a treat!

[element]

Re: Another Marina brake problem

Got it out Had to modify again the twin leg puller with the grindstone on its legs & then fitted a big jubilee clip across (between the pistons) around each leg of the puller and tighten up as much as possible then a bit of 2mm steel over the top for the pin to push down on.. Worked a treat. Given up on the piston refurb & have ordered a new one...