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Ok, so I have a new '91 Spider. Brake pedal was high and hard. I mean, scary hard - it was almost like I didn't have a brake booster giving me "power brakes". I could stop the car safely (and lock up the wheels if I wanted), but only with what I considered a large amount of pressure. Pedal also had really high engagement.

Brake fluid was dirty, probably several years old. So last night I flushed out the old fluid to see where things stood with the booster - used the Motive Bleeder system from IAP. I know how to flush and bleed brakes. This was pretty easy, so that's not my question. I've had the same result with the bleeder and the two man method. Regardless, I feel my methods are sound.

With fresh fluid and bleed, the brake pedal is now much lower and lighter to the touch, with long pedal travel - just like my other Spiders have always been. I've never liked it this low. Brakes are still there, and I can lock them up at full travel. Pedal is not spongy and pumping them up doesn't make the pedal higher. Pads are not excessively worn, nor are the rotors. Master cylinder is fine and not leaking. I don't think this is an air in the lines issue, and with the bleeder, I don't see how air would've gotten in the lines (also, I used the Alfa method).

SO - I guess my real question is, is there any way that I can find a happy medium between high and hard, and low and easy? What would've explained both symptoms, as all the braking components check out? I feel this is essentially a Spider foible, and was curious if anyone has accurately addressed it, or if it can be addressed. I find it to be a bit of a quirk. Also, I'm not about to throw thousands into a working brake system - it's a matter of should I bother trying to bleed it more, etc.

I don't like a high hard brake pedal, nor do I like a soft, low one. I want that good confident feeling when I press on the brakes. No Spider has ever really given me that, even when a professional has worked on the brakes. I think that perhaps fresh rotors and pads might bring the pedal up, but that seems like a waste.

Would more bleeding help at all? I did all the professional stuff and tricks to get rid of air, and I'm not sure that's even the issue here. My brake pedal feels no different than my Honda Civic. I feel like I should be able to do a bit better than that!

Thoughts?
 

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One thing that I have discovered is that when bleeding the rear brakes if you have the rearend up higher than the front wheels it is very difficult to get the air out of the lines.
If no air got in the lines at any time then it doesn't make since. One other thing to look at is the air valve coming out of the intake. I've never had trouble but it could have been stuck and bleeding opened it up somehow. A hard pedal is usually the booster gone bad. I am replacing the one on my 91 this weekend. I have a hard pedal and I hear a hiss when lifting just slightly. No hose leaks..
 

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Lots of reading material here: brake pedal travel with ideas and theories but not definitive conclusions...

Also, Alfa advises bleeding the brakes in pairs (left side & right side). I don't know if that has to do with keeping the pistons for the dual circuits in synch or if it has to do with a brake failure warning system.

 

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interesting..i run my brakes without a power booster, have no trouble stoping the car, pedal is frim, but not so it might be ' scary ' but then i am running 4 piston calipers on the front of my car, that might be why my pedal feels fine..
 

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low brake pedal

Since the car is new to you, what size is the master cylinder bore? I don't know if you can tell from the outside. If someone replaced the master with a smaller ID you would end up with a longer pedal travel to push the amount of fluid needed for stopping.

I went the opposite way and installed a larger ID master which resulted in a slightly higher firmer pedal.
 

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I made my brakes feel firmer (best they have ever been) when I bleed the master cylinder and tighting up my front wheel bearings. This was after bleeding the brakes several times and not happy with the feel.

All I did was loosen the connections (one at a time) at the master cylinder.

The other thing that was causing a problem (long brake peddle) was loose/worn front wheel bearings that was causing "pad knock back" which causes dead play between the pad and the rotor.

The loose bearings were causing the rotors to knock back the pads into the calipers thus causing a longer travel of the brake peddle.

If you brake right after braking no problem but if it's a bit before you brake again then the loose bearings had a chance cause the rotor to push the pads back and the long peddle is back...............just my opinion

IMO you have some air in the system too.

I do the right rear first then left rear, front right and finally the left front. I also pull the pads out and push the caliper pistons back into the calipers before bleeding to get the old fluid out from behind the pistons.
 

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Changing pads and discs will have no impact on pedal feel (ie travel or soft/hard). This is a consequence of the hydraulic system.

It does sound like you have some air still. 105 brakes in good nick are very sensitive, with a light pedal, some travel (but not a lot) and a lot of power (will put you through the windsheild). If you haven't got this, there is still some work to do.
 

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My '76 Spider brake pedal is considerably more firm than my '91 Spider. Someone posted a while back with the same problem on a later model Spider, and said the solution was to bleed using "Speed Bleeders". I bought a set last year, but have not yet done the bleed process (this may be covered in the discussion link posted by ghnl).
 

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Discussion Starter #9
Thanks for the replies everyone. It looks like I even responded in that old thread about having the same issue in a Spider I used to own. That thread pretty much summed up my experiences. I will give it another shot, but as for now, the pedal feels like it always had in my Spiders. Again, it's not spongy and pumping them up doesn't increase the pressure or raise the pedal. It's just a longer, softer travel. Not sure why it was so incredibly hard and high before I bled them.

Anyway - thanks for the tips. I did do the proper sequence and the pro bleeder always had 10 psi shooting fluid into a catch container. No back pressure ever. Even banged on the calipers to loosen some bubbles.

Will try it one more time just to be sure I got it right. I feel like I'm having deja vu inside of deja vu inside this thread. I've definitely been here before. But I guess brake work is definitely one place where it's good to second guess yourself.
 

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I get the high and very firm pedal occasionally when I have just started up. Its a bit disconcerting as I have to really press hard to get any brake action. Then it clears and the brakes go back to normal. The advice I have had from this forum is that it is probably the one way valve, that allows air to be sucked in and create the vacuum for the servo, that is sticking.
It certainly seems like this - until it frees itself there is no servo assistance so the brakes are just like old style, unassisted ones. Then the valve frees up, the servo kicks in, the pedal is drawn down lower and the brakes become normal, exactly as you describe yours.
I suspect that in changing the fluids etc. you have unstuck this valve.
 

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The Motive Bleeder or pressure bleeder (attaches to the reservoir and provides pressurized fluid) is a great tool, but in some cases, you just can't beat the old foot bleed method. The main difference is you can only safely get 10 - 30 psi with a pressure bleeder, but foot bleeding can easily get you 500 psi or over 1000 psi with the engine running. The higher pressure entrains any trapped air in the fluid allowing it to be flushed downstream. I think the ideal setup is to use a pressure bleeder while pumping the pedal. This will entrain the air and keep it moving. You'll need to have a really good connection at the calipers or things can get very messy:p
 

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ocduff,

Do check your front wheel bearings for tightness if they are loose it will give you "pad knock back" which does give you a longer brake peddle travel. Made a big difference for me.
 
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