Brake issues

[scotty8370]

looking for assistance / advice

I have Gran Turismo S and recently upgraded my disks/pads and added braded hoses. Filled the reservoir and progressed brake bleed but not getting pressure at rear and driver side, passenger side is showing pressure, checked master cylinder and one exit port not showing pressure, got new master cylinder and this is also showing same issues (no pressure at brake bleed screws etc), so it looks like all the individual parts are ok but can't get the fluid pressure at calliper (other than the front passenger side).

 

[conaero]

Don’t you require SD diagnostics to bleed the brakes on a GT and QP, something in my mind seems to recall this?

 

[Oneball]

What method are you using to bleed?

What is the fitting at the caliper end of the hose?

My two thoughts are you aren’t able to get fluid to pass through the abs unit.

The new hoses unions are incorrect.

 

[Oliver6796]

Not sure if this is at all relevant on road cars but work 1 calipers at a time, unlock bleed,press pedal then lock before releasing pedal. Pressure on pedal then unlock bleed again. Lock again before releasing pedal (two man job. on ON off OFF) also try pressurising the pedal overnight to open up the return to the resivouir so any air locked in can track back up.

 

[Oliver6796]

What method are you using to bleed?

What is the fitting at the caliper end of the hose?

My two thoughts are you aren’t able to get fluid to pass through the abs unit.

The new hoses unions are incorrect.

If unsure on wrong unions I guess pull the line off and see if you get pressure coming out of the union alone

 

[Zep]

When I bled the brakes on my GS, I was advised that if I used a pressure system, like an Eazibleed, or a vacuum bleeding system, like an air powered bleed bottle, this would bypass the ABS unit valve issue. I used the Eazibleed and it worked perfectly. Not sure if this advice applies to the GT / QP, but it would be reasonably cheap to find out.

 

[scotty8370]

Don’t you require SD diagnostics to bleed the brakes on a GT and QP, something in my mind seems to recall this?

thanks don't have a SD unit so not sure?

 

[scotty8370]

What method are you using to bleed?

What is the fitting at the caliper end of the hose?

My two thoughts are you aren’t able to get fluid to pass through the abs unit.

The new hoses unions are incorrect.

Thanks, fitting on calliper is standard nipple the hoses I upgraded to steel beaded hoses so would have had a fully drained fluid system, initially though master cylinder fault but new unit as said was same issue, did consider ABS but the front passenger is getting pressure would ABS not stop flow to all sides?.. but it is looking likely that ABS mat be root cause, but I have no idea how to address thus, do you, thanks....

 

[scotty8370]

When I bled the brakes on my GS, I was advised that if I used a pressure system, like an Eazibleed, or a vacuum bleeding system, like an air powered bleed bottle, this would bypass the ABS unit valve issue. I used the Eazibleed and it worked perfectly. Not sure if this advice applies to the GT / QP, but it would be reasonably cheap to find out.

I've been doing the two man job, one pumping peddle the other bleeding at nipple, never used the vacuum system but called the independent specialist and they also pressurised the reservoir to bleed brakes, might get this and give it a go..what's the ABS valve issue? thanks again

 

[scotty8370]

If unsure on wrong unions I guess pull the line off and see if you get pressure coming out of the union alone

the new hoses etc are all good, supplied by maserati specialist for my model, think it sounds like the ABS valve issue, whatever that is...

 

[scotty8370]

Not sure if this is at all relevant on road cars but work 1 calipers at a time, unlock bleed,press pedal then lock before releasing pedal. Pressure on pedal then unlock bleed again. Lock again before releasing pedal (two man job. on ON off OFF) also try pressurising the pedal overnight to open up the return to the resivouir so any air locked in can track back up.

that pretty much what I carried out, two man job pump peddle, also left the reservoir to gravity feed the system till no air bubbles shown, the repeated bleeding still getting nothing at three wheels, other responses are indicating a possible abs valve causing the issue but not sure what that is or how to get round it or eliminate that as a cause. thanks again

 

[Oneball]

If you are bleedimg it manual I don’t think an issue with badly fitting hoses would cause your problem.

Get an Eazibleed or something equivalent these are usually able to get enough fluid through the abs unit (pumping the pedal can often not get past an air lock in there you just compress the bubble and releasing the bleed nipple on the caliper doesn’t do anything, some older ABS units used to have bleed nipples on the unit itself).

 

[mjheathcote]

As already said above, bleeding the the old fashion manual way with modern cars with ABS does not always work.
Pressurised brake bleeding kit is your best bet, much easier too.

 

[Zep]

I've been doing the two man job, one pumping peddle the other bleeding at nipple, never used the vacuum system but called the independent specialist and they also pressurised the reservoir to bleed brakes, might get this and give it a go..what's the ABS valve issue? thanks again

The issue is the problem you have, you pump the pedal but no fluid goes through. Pressure bleeding is the way forward in my view.

 

[scotty8370]

If you are bleedimg it manual I don’t think an issue with badly fitting hoses would cause your problem.

Get an Eazibleed or something equivalent these are usually able to get enough fluid through the abs unit (pumping the pedal can often not get past an air lock in there you just compress the bubble and releasing the bleed nipple on the caliper doesn’t do anything, some older ABS units used to have bleed nipples on the unit itself).

Thanks heading to halfords for eazibleed and give it a try...

 

[Oneball]

When using one I’d suggest ensuring everything is sealed properly by attaching and pressurising it without any fluid in the Eazibleed first and if it’s ok then fill it up. If the seal on the reservoir lid isn’t good it’ll leak fluid everywhere

Hope that makes sense.

 

[scotty8370]

got an eazibleed unit, pressurised the system, did get some air out of some of the nipples, looked promising. with engine off can feel a brake can say if it was holding wheel from turning as only by myself) but it does spring back, started the engine and had no brakes again, do I have to get the ABS set via computer or so.ething like that?

 

[Ralph_Manders]

I had similar issues when I changed to ss brakelines, and wasn’t even able to get good pressure with a vacuum bleeder and a compressor. But google was my friend and I read an article of Aldous Voice on bleeding ferrari systems. So I got myself a Sealy vs820 pressure bleeder. Fits perfect on the Maserati and it’s a one person job now. No fancy computers needed. You would only need a computer if you need to bleed the smal fluid reservoir inside the ABS unit, which you do not refresh with a normal bleed. Alternative way of getting that oil refreshed is first flush the entire system, than go for a ride and make shure the ABS kicks in a couple of times, thus releasing the old fluid in the system and retaining fresh fluid. Than reflush the system (easy with the pressure bleeder) and presto. I needed about 1.5 liters of brake fuid for that.

 

[Oneball]

got an eazibleed unit, pressurised the system, did get some air out of some of the nipples, looked promising. with engine off can feel a brake can say if it was holding wheel from turning as only by myself) but it does spring back, started the engine and had no brakes again, do I have to get the ABS set via computer or so.ething like that?

Wouldn’t have thought so.

I reckon you’ve still got air in it. I would go around all the new unions and make sure they are tight. Then just do it again. I’d recommend bleeding the furthest from the master cylinder. Press the pedal a few times with the engine running. Do that one again. Then do the other three.

 

[scotty8370]

I had similar issues when I changed to ss brakelines, and wasn’t even able to get good pressure with a vacuum bleeder and a compressor. But google was my friend and I read an article of Aldous Voice on bleeding ferrari systems. So I got myself a Sealy vs820 pressure bleeder. Fits perfect on the Maserati and it’s a one person job now. No fancy computers needed. You would only need a computer if you need to bleed the smal fluid reservoir inside the ABS unit, which you do not refresh with a normal bleed. Alternative way of getting that oil refreshed is first flush the entire system, than go for a ride and make shure the ABS kicks in a couple of times, thus releasing the old fluid in the system and retaining fresh fluid. Than reflush the system (easy with the pressure bleeder) and presto. I needed about 1.5 liters of brake fuid for that.

Thanks, I did get air out the system with easy bleeder but some of the bleed screws I just felt like there was no real flow, just dribbles of fluid from the nipple. What pressure did you pressure the system too and when you cracked your nipples did you get a good flow of fluid or just a dribble? did you bleed with the engine off or on or key in the ignition to power up the ABS, thanks in advance for clarity and support.