Fiat f 115 brakes

[fiat 9090]

Hi I'm wondering can anyone throw s bit of light on my brake problem ,I have an f 115 and the left hand brake pedal is going to the floor I have tried everything master cylinders are good I put new seals in and the piston is good but it's still losing fluid any help would be gladly appreciated as I'm pulling my hair out at this stage

 

[agrimax]

I'd think the piston seal in the brake housing in the rear axle needs replacing. The fluid will be going into the axle oil.

 

[balerman]

I'd think the piston seal in the brake housing in the rear axle needs replacing. The fluid will be going into the axle oil.

Yep not really a big job,trumpet housings off,may as well replace the brake discs while in there.

 

[fiat 9090]

Sorry when I said I put seals in I meant seals in the trumpet housing,but I still don't have a brake

 

[balerman]

Sorry when I said I put seals in I meant seals in the trumpet housing,but I still don't have a brake

Trailer brake valve? Not many other places it could be going.

 

[fiat 9090]

Trailer brake valve? Not many other places it could be going.

No it's the left hand side and I blanked the pipe going from master cylinder at the top of the trumpet housing and I have a good pedal but when I reconnected it the pedal went to the floor

 

[pail of ale]

Must have nicked one of the seals if the fluid keeps going away . Is it bled fully?

 

[Half Pipe]

Is it correct oil? Although both sides would be doing the same if it was oil.
Remember our 110 doing similar after a top up with brake fluid!

 

[bazza3034]

I was thinking the same you make have nipped the seal when replacing the piston easily done

 

[fiat 9090]

Must have nicked one of the seals if the fluid keeps going away . Is it bled fully?

I thought the same but when I stripped it again the seals were perfect ,but to be sure I put in another set ,I also made sure the grooves were clean and I gave the piston a rub of light empty paper,it really has me baffled because I have done loads of them before

 

[fiat 9090]

Is it correct oil? Although both sides would be doing the same if it was oil.
Remember our 110 doing similar after a top up with brake fluid!

I changed from lhm to engine oil just for the sole purpose of getting to the root of the problem ,the only difference is the master cylinder takes a few more seconds to reload ,I have it down to the inner seal on the piston as I can see almost no fluid coming out of the outside of the piston ,it seems to be coming out behind as is flows out of the bottom hole of the main housing

 

[fiat 9090]

I was thinking the same you make have nipped the seal when replacing the piston easily done

I checked that