SR20 brakes in RT142 pedel goes to the floor??

[pisso001]

Hi all,

I just put all my S13 gear in my rona.. All went sweet and had no troubles until we tried the brakes.. We gave them a good bleed before hand but still no go... It pumps up so there is feel (still spungy and crap) then as soon as you let the brake up again its gone and goes to the floor again... We then bled the brakes again and again tonight still with no luck.. There are no leaks that i can see and everything seems normal.. What is wrong? Need to get it fixed as ive got a day at the track this weekend...

Thanks,

Pisso.

[thechuckster]

I just put all my S13 gear in my rona.. All went sweet and had no troubles until we tried the brakes.. We gave them a good bleed before hand but still no go... It pumps up so there is feel (still spungy and crap) then as soon as you let the brake up again its gone and goes to the floor again

master cylinder no good?

[SillyCarS]

when you say no leaks did you check inside drums?

also if it has leaked on the shoe instead of buying new ones the trick is to soak them in petty and set them on fire

[pisso001]

Master Cylinder is pretty new and seems fine i have rear discs... Any other ideas.. Its quite random..

[Crazyracer]

S13 stuff is discs all around, so it wont be stuck in the drums and should be pretty obvious dripping from the calipers if the seals there are gone.

See if the fluid level in the brake fluid reservoir is going back up slightly when you press the pedal down.

If the seal on the valve that stop fluid returning to the reservoir is stuffed, you may be able to develop enough pressure to bleed the brakes, but when you put some real pressure on the system, the fluid just leaks back up into the reservoir and the pedal feels spongy.

If it happens, your master cylinder will need replacing or re-kitting. If its an alloy casting I'd just replace it. They don't reco all that well.

Other possibility is that the master cylinder you're using is just way too small to go with the S13 brakes.

[pisso001]

Only have S13 gear up front. Stock corona discs on the back atm.. That sounds more like it though.. Ill have a look tomorrow. What should it do? I was also thinking about taking it to a mechanic to get them to pressure bleed it.. Any good ways to check whether the master is stuffed before i do that?

Thanks,

Pisso.

[crowncustom]

Is the master cylinder the right bore diameter for these particular brakes?
Is the proportioning vavle doing its job?
Cheers Brett.

[pisso001]

No idea... I dont know of any upgrades that fit my booster and I think someone is running the corona/pug/hilux conversion on the stock master in a RT142 so it shouldnt it cop it, shouldnt it?

Thanks,

Chris.

[SillyCarS]

it should still diplace fluid anyway not matter what the size, just requires different force for each bore

[pisso001]

So the stock cylinder should work just might be a bit spongy? So that leaving it that maybe the cylinder is faulty? Is it possible to get some sort of air lock that is hard to get out? Although every time we have bled it we get a few bubbles but always end up with nice clean fluid without air...

[SillyCarS]

are you bleeding it with a fine tube so you can see bubbles?

pressure = force / area

so yeah bigger cyl a bit stiffer but your should still be able to break without hitting floor pan

bias? fu*k i cant think of anything else

[pisso001]

Yeah had the fine tube... Hmmm yeah im stumped too.. I think ill just take it to a mechanic get them to check the master and or pressure bleed it..

Thanks for your help all the same..

Thanks,

Pisso..

[crowncustom]

Have you bled the master cyl?
If not, all you need to do is crack each line coming out of cyl,do rear brake circuit first then the front.Make sure you have a rag to hold over the lines as fluid will squirt everywhere or just let it squirt then staight after doing it pour boiling hot water over the affected areas.
Other than this its a kit or new cyl.
Cheers Brett.

[pisso001]

Yeah i thought of doing that.. Sam-131 pointed out in another thread that the calipers might be upside down and sure enough i just went to have a look and they are so i think that might be the main problem.. Will probably bleed the master and the lines really well after i change them around.. Hopefully thats the problem..

Thanks for all the help,

Pisso.

[cooter]

i had a little trouble with this when i put my STOCK brakes back together. when i put it all back together the pedal would go all the way to the floof and then only just start working. turned out to be a combination of a few things.

id put about 2L of fluid through it thinking it was a bleeding prob. turned out it still had a real small amount of air in it.

my front brake caliper slides where ungreased and nearly siezed.

and my pedal wasnt adjusted proper.

i originally thought it was the master but i put a new one on and it didnt change.

hope that might help ya
craig