SiR Shizzle

Hi Guys,

Just picking your brains.

The car has just had to have brake lines replaced at the centre (where the rear subframe meets the main chassis) as they had perished.

I have picked the car up and done approx 50 miles in it.

When I stamp on the brakes I get good positive braking, but with light or progressive pressure the point at which the brakes 'bite' is much lower.

I previously had something similar on my CRX and it was the MC. Am I safe to assume it's the same situation here? Bad brake bleeding couldn't be the cause could it?

Just as a side note, this all happened as the car was having it's UK MOT test (yearly roadworthy test) and during the brake test it split the lines. I'm thinking that a brake test that caused brake lines to burst would also put pressure on seals on an old MC and cause that to fail too - and also it is currently on 130k miles so it's not unreasonable to think it's due for replacement soon.

Just want some opinions before I buy a new MC or demand a re-bleed.

Many thanks

Dave

tbpom1003

Hi Dave. Basically, you need at least two brake fluid bleeding if you replaced brake line, caliper or anything that should open the system.
There should be still tremendous amount of air left in there. Air just don't get out at one time. It is always stuck somewhere fluid doesn't really flow.
Try bleeding after you spend a tank of gas.

Btw, when you say you stamp on the brakes means you slam the brake? I'm not sure about master cylinder, but check if there is any leakage around your master cylinder. Also, check if your fluid level is constant after few days of driving

Car Analogy

+1. Its air in the lines. Bleed several more times.

Since you replaced a metal pipe in the center of the system, that air will be difficult to get out. I would jack one end at a time to bleed, so that end is a little higher, so air will flow that way more easily. Then gravity bleed again the normal way (car level).

SiR Shizzle

Thanks Guys,

Yes - by 'stamp' I mean 'slam'.

There's no evidence of leakage anywhere as far as I can see, I'm going to call the garage and get their opinion.

Would a 'pressure bleed' help?

shind3

Try this:
http://www.amazon.com/dp/B000MXW2EM/...I1P3GICZSS7MM4

Slowcrash_101

Whenever I remove any part of the brake system I do a manual bleed first, and a gravity bleed second. If I really need to get all the air out I'll use the shop pressure bleeder, but that's only for special occasions.

Utah S2K

Top of this forum blue stickies.

FAQ, Maintenance, DIY
Suspension and Brakes
"Billman's gravity bleed procedure"

Takes more time but should remove the air I believe others are correct in noting.

Utah

SiR Shizzle

Thanks guys