Brake pedal hard after bomb replacement?

[merlin's S4]

Need some help. I've replaced my Bomb today with one from Paul at Custom Autocraft. I followed ths guide http://www.20v.org/brakprob.htm but now it's all back together my brake pedal is rock hard with or without the engine running. Power steering seems fine and I've done the lock to lock thing to bleed the system. So what have I done wrong??

[iain1067]

odd i had one off him too and had the same problem as you, never did get round to fixing it, sorry i can't be more help

[bertman]

Is your power steering pump ok,and did you give the hydraulic system a good flush.
No use installing a new bomb with the crappy old oil in the system

[merlin's S4]

Drained the system but didn't flush it. Refilled with 1L of fresh fluid. And yes it was the green stuff! I've never had a problem before with the brake pedal feel, I just couldn't pump it more than a few times with the engine off so thought I'd replace the bomb. Now I can't even drive the thing until I suss the problem. Is simply flushing the system likely to solve this problem?

[bertman]

Do the brakes work with this problem?

[s2_bo]

I did this about 2 months ago with a new bomb from Custom Autocraft because my one was leaving the pedal rock hard when engine off and it always started up with the brake assistance warning light.

After the new bomb was fitted everything was fine but in the last couple of weeks the warning light as been coming back on and the pedal is now rock hard again when engine off.

I think my power steering pump is to blame though as its got about 2mm - 3mm shaft play.

Good luck in sorting it out though Tris.

@ Rob, yes the brakes still work as the pedal softens when the engine is switched on and the PAS pump starts to pump fluid.

[merlin's S4]

Do the brakes work with this problem?

It's not possible to push the pedal down far enough to stop quickly. It's like trying to stop by pulling up the handbrake!! It feels like there's no servo assist which would suggest that the hydraulic system isn't working. Is it possible that something in the bomb could block the fluid from entering the high pressure line to the servo?

[bertman]

Its worth checking the small mesh filters that sit inside the hydraulic line from the pump to the bomb,they sit inside the bolt the secures the banjo connection.
Found that they are worth a clean to remove trapped debris which can restrict the flow of the fluid.
Having the complete opposite to you guys,soft pedal-then hard pedal,this is after changing out the PAS pump and bomb together

[s2_bo]

Ok, that sounds a lot more serious than what normally happens when the bomb packs in.
Tris i suggest you email Paul Fernandes from Custom Auto Craft and see what he has to say, maybe he's heard of this before and knows how to sort it out.

[bertman]

Brake issues the:
Thorn in my side
Pain in my ***
Bane of my life
etc
etc

[S2central.net]

Checked the servo yet ?

Or the hydraulic pressure from the pump - should be approx 140bar - one hunderd and forty - be afraid - needs special guage.

Paul

[merlin's S4]

Checked the servo yet ?

Or the hydraulic pressure from the pump - should be approx 140bar - one hunderd and forty - be afraid - needs special guage.

Paul

Not yet but then neither is straight forward! I would've thought (hoped) that both are ok as there was never any problem before replacing the bomb today.

[newsh]

You havent left the little plastic plug thing in the bomb have you? Sounds like its not pumping up. Other wise bleed procedure again and check the fluid level, if it was working before it must be a bad bomb. Strange though because even a bad one will give you a couple of pumps..

[merlin's S4]

Fingers crossed but it appears as though I've sorted it this evening. I flushed out the fluid and considering I put a fresh litre in yesterday, it was looking pretty murky! I took off the hoses from the reservoir and the pressure hose from the pump to bomb and gave everything a good clean before putting more fresh green goo in the system. After following the self bleeding process with the steering and giving the engine some revs to get the pump spinning quicker the brake pedal released!

I've since been out for a spin and all seems fine (clinging onto wood here!!). I can only assume that either a valve was stuck inside the bomb or there was some dirt trapped somewhere in the system.

On a side note, as Bo suggested I contacted Paul at Custom Autocraft. He replied quickly and was very helpful and even though he wasn't sure about the cause of the fault, he offered to send me a new unit to try. Hopefully I won't be needing this now but a big to the man!! Top bloke!!

[bertman]

Fingers crossed but it appears as though I've sorted it this evening. I flushed out the fluid and considering I put a fresh litre in yesterday, it was looking pretty murky! I took off the hoses from the reservoir and the pressure hose from the pump to bomb and gave everything a good clean before putting more fresh green goo in the system. After following the self bleeding process with the steering and giving the engine some revs to get the pump spinning quicker the brake pedal released!

I've since been out for a spin and all seems fine (clinging onto wood here!!). I can only assume that either a valve was stuck inside the bomb or there was some dirt trapped somewhere in the system.

On a side note, as Bo suggested I contacted Paul at Custom Autocraft. He replied quickly and was very helpful and even though he wasn't sure about the cause of the fault, he offered to send me a new unit to try. Hopefully I won't be needing this now but a big to the man!! Top bloke!!

Glad you got it sorted mate,hope it stays good,wouldn't hurt flushing again,did mine about 5 times before I was reasonably happy the fluid was clear,That way you get rid of most of the crud in the system.It will help prolong the life of the hydraulic system