(G) Uno stopping power

hi all
I recently acquired a 2003 1100 uno panel van that I converted to a family car.
My other car is a 93 prelude with discs all-round no abs and stops every time in no time.

Since I bought the uno the brakes were not very good until Monday I discovered that the back silencer on the original exhaust came lose and knocked the brake pipe going to the LRW to pieces. I replaced this pipe and installed a free flow exhaust, bleeding the brakes all round and all of a sudden the brakes improved drasticly. But only for a while, when I hit the brakes there were nothing. After returning home very slowly I discovered that the reservoir were empty. I immediately investigate this thinking that maybe one of the rear cylinders was leaking, but to my surprise no leaks were visible.
So I topped up and bled the whole system again and all ok. After about one week the same happened and I noticed the reservoir runs empty when the car is parked. I had the back cylinders overhauled and still the same.
I then removed the master cylinder and started stripping this. This is a Bosch
Unit with the number 421469 on the side. When stripping this I came to a white plastic washer type ring. I eventually broke this ring to get the parts out.
1.Is this ring of any use???
2.after installing a new kit without this ring I could only get the rear part to bleed thru??
3.After I broke this white plastic part, all the parts went flying: bang: and I am not hundred present sure if I assembled it correctly. I do have the Haynes’s manual but the master cylinders in the book are completely different to my Bosch unit. Please help??? pic if possible on the Bosch unit

Can't help with the master cylinder, but it may be the cause of your fluid loss. When the back seal fails it can cause brake fluid to leak into the servo, which then gets sucked into the inlet manifold. If you noticed white smoke coming out of your exhaust then that's may be what is happening (as long as it's not your head gasket!)

Look on Ebay for master cylinders as they often turn up for not very much. It's probably better to fit a new one than try and re-build an old one anyway.

Good luck!

I recently replaced my master cylinder and bought it new! which was 40 odd £££, could of bought the repair kit, but for that price (and brakes are brakes) esp as is the misses car so take no chances, on removal the servo was half full of brake fluid, as i'd been topping it up for 2 weeks and wondered where oil was going, no drips or leaks, now brakes spot on! Ant!

I've also seen at least one brake servo that was full of brake fluid - well about a litre! - far more than the capacity of the brake system

Another sign of master cylinder trouble is when you bleed the brakes, they work OK, and then need bleeding again later.

-Alex

thanx all, did after all replaced the master cylinder and now stopping is good.

Glad to hear that another Uno has been sorted