cobraboy
Well-Known Member
Evening all
Am trying to get to the bottom of a braking issue and wondered if anyone else was having, or has had problems.
Three years ago all the caliper's were removed and re sealed. Periodically the straight line stopping has been, well iffy ! the car will not pull up straight under hard braking.
Lots of time sent on all bushes, links. arms, idler, etc etc.
Now gone 360 and come back to front caliper's.
Have bought another seal kit and on fitting have found it impossible to fit the large piston by hand, it was tight to get out. I part pushed out the pistons on the car before removing the caliper and was surprised at the amount of pedal effort needed to move the pistons.
The small pistons can be pushed into the caliper by hand. Without the seals in the caliper all the pistons will drop into their bores.
So with a measuring stick I have found the large pistons measure 57.2mm and the small ones 40.4mm. I wondered if they were supposed to be 57mm and 40mm and the remanufacturer made them finished size and then when they were plated they ended up too big ?, as I threw my Girling pistons three years ago I guess I'll never know.
I telephoned a supplier today and he kindly measured his stainless steel pistons and the result was the large were 57.08mm.
I cannot do anything with a plated piston, but I can linish a stainless piston, so I think I will purchase two stainless pistons and get them to 57mm and see how they fit.
The other thought with this would be seal sizing, the seals are made by Nelson and the supplier who measured the pistons has said that they have used their kits for many years without issues, so I guess I have to discount the seals being too big. Although I did wonder about the material, it is not rubber, maybe its EPDM and maybe it is not as giving as rubber and the same section size is too big ?
If all this is making your head hurt spare a thought for me ! I need some positive vibes guys and a solution please
Am trying to get to the bottom of a braking issue and wondered if anyone else was having, or has had problems.
Three years ago all the caliper's were removed and re sealed. Periodically the straight line stopping has been, well iffy ! the car will not pull up straight under hard braking.
Lots of time sent on all bushes, links. arms, idler, etc etc.
Now gone 360 and come back to front caliper's.
Have bought another seal kit and on fitting have found it impossible to fit the large piston by hand, it was tight to get out. I part pushed out the pistons on the car before removing the caliper and was surprised at the amount of pedal effort needed to move the pistons.
The small pistons can be pushed into the caliper by hand. Without the seals in the caliper all the pistons will drop into their bores.
So with a measuring stick I have found the large pistons measure 57.2mm and the small ones 40.4mm. I wondered if they were supposed to be 57mm and 40mm and the remanufacturer made them finished size and then when they were plated they ended up too big ?, as I threw my Girling pistons three years ago I guess I'll never know.
I telephoned a supplier today and he kindly measured his stainless steel pistons and the result was the large were 57.08mm.
I cannot do anything with a plated piston, but I can linish a stainless piston, so I think I will purchase two stainless pistons and get them to 57mm and see how they fit.
The other thought with this would be seal sizing, the seals are made by Nelson and the supplier who measured the pistons has said that they have used their kits for many years without issues, so I guess I have to discount the seals being too big. Although I did wonder about the material, it is not rubber, maybe its EPDM and maybe it is not as giving as rubber and the same section size is too big ?
If all this is making your head hurt spare a thought for me ! I need some positive vibes guys and a solution please