01-23-2007, 02:51 PM
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Brake Pedal Hardened Stiff: Brake Failure
I have a 1987 Alfa Romeo Milano Verde. One day, I was driving, and when I proceeded to brake, the brake pedal was completely stiff and would not budge, and I could not brake at all so I couldn't stop. What could have caused this?
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01-23-2007, 03:12 PM
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I searched around the forum, and looks like common thing is the ABS pump and accumulator. Sound about right?
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01-23-2007, 03:53 PM
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Location: Benicia, CA
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Yes, the most common cause of a "hard" pedal is insufficient system hydraulic pressure. The root causes can be a bad ABS Pump; blown ABS Pump fuse, a bad ABS accumulator, low hydraulic fluid level.
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01-23-2007, 03:59 PM
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As a few others have found, with some of those causes you can still brake the car even if the pedal is amazingly stiff.
In fact only time i have caused skid marks from braking is when my old ABS pump failed!
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'88 Alfa Romeo Milano Verde - 24V, '87 Platinum 3.0 (for sale), 94 LS parting out
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01-24-2007, 06:26 AM
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Location: Columbia SC
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Mine occasionaly does this but then starts working again. It only does it in hot weather so I am ok for a few more months. I suspect that it is the pump, or the relay, or the pressure switch. If it gets worse I will start swapping out parts, one at a time, starting with the easiest.
Ed Prytherch, Columbia SC
74 GTV
79 Spider
88 Milano Verde
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01-24-2007, 12:26 PM
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 Quote:
Originally Posted by alfaparticle
Mine occasionaly does this but then starts working again. It only does it in hot weather so I am ok for a few more months. I suspect that it is the pump, or the relay, or the pressure switch. If it gets worse I will start swapping out parts, one at a time, starting with the easiest.
Ed Prytherch, Columbia SC
74 GTV
79 Spider
88 Milano Verde
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Its good though, the pump is a 15 minute job, its just messy!
My pump did that to me once and its scary to all of a sudden have to press 20x harder to achieve the same braking ability, at least you can still stop!!
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'88 Alfa Romeo Milano Verde - 24V, '87 Platinum 3.0 (for sale), 94 LS parting out
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01-25-2007, 10:26 PM
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First determine if the ABS pump is working. If it is not, check the fusible link by the coil. Start with the basics before you start replacing parts. The factory shop manual has a good troubleshooting section for the ABS. I had the same problem years back, it was the fusible link. Good luck.
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ANDREWG
[url]www.garciaalfaracing.com[/url]
73 GTV - new restoration project
82 GTV6 ITS #86
85 Spider Graduate
88 Milano Verde - needs a motor, hum...
91 164S Recaro
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01-28-2007, 08:04 PM
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I had the same problem and it was due to a worn out ABS pump. I took apart the pump and the motor was frozen. You can stop the car about 20 times after the pump fails, but you cannot stop the car after 21 times. I purchased a new pump and then bought two used pumps. You can buy a pump from Alfa Part Exchange located in Hayward, CA.
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01-28-2007, 08:21 PM
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So I tried to see it the pump turned on when I depressurized the whole system. I depressurized it, and turned it to the on position. The pump intialized and clicked to repressurize the system. So I guess it's not the fusable link. Where is that ABS link/fuse? Pump/accumulator problem? What does the accumulator do?
This Milano only has 73k miles on it btw. |
01-28-2007, 08:36 PM
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This failure mode is not uncommon. I consider it to be yet another reason to get rid of the ABS system on these cars.
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01-28-2007, 11:10 PM
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Quote:
Originally Posted by Greg Gordon
This failure mode is not uncommon. I consider it to be yet another reason to get rid of the ABS system on these cars.
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Now, there is much more information available and if a SPICA injection pump fails it doesn't automatically call for a carb conversion. Of course, some people CHOOSE to convert to carbs, but it's not the only good option.
The same is true of the ABS system. It's fairly easy to diagnose, and there are inexpensive GM cross-referenced parts for everything except the Master Cylinder.
I actually prefer the feel of the ABS system in the Milano; I have 1 Milano with ABS and 1 without and have driven them back to back over the same roads. And, as Nizam has shown us, it can be a definite advantage on the track.
So - there are options, I don't think ABS removal should necessarily be the default choice.
Joe
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01-29-2007, 09:50 AM
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Quote:
Originally Posted by oliverr871
So I tried to see it the pump turned on when I depressurized the whole system. I depressurized it, and turned it to the on position. The pump intialized and clicked to repressurize the system. So I guess it's not the fusable link. Where is that ABS link/fuse? Pump/accumulator problem? What does the accumulator do?
This Milano only has 73k miles on it btw. |
The next step is to test the accumulator. (The accumulator allows the hydraulic system to build up pressure, so the brake can be applied a number of times before the pump kicks back on.) One test method is (with the engine running, car in neutral, parking brake on, ABS pump not running) fully engage and release the brake pedal repeatedly and count the times it takes before the ABS pump kicks in. The typical number is 7-9 times. If its less, the accumulator could be bad, causing the pump to over-cycle, possibly overheat and seize. Another indicator of a bad accumulator is the bleed down time after the system pressurizes. If the ABS pump kicks in after the car sits idle for say an hour, the accumulator could be bad. A tight hydraulic system with a good accumulator can hold pressure overnite.
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01-29-2007, 10:48 AM
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Joe: In my case this is not a knee jerk reaction but is a well thought out personal choice. I consider the increased risk of a total brake failure to far outweigh the benifits of the system.
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01-29-2007, 01:39 PM
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Quote:
Originally Posted by Greg Gordon
Joe: In my case this is not a knee jerk reaction but is a well thought out personal choice. I consider the increased risk of a total brake failure to far outweigh the benifits of the system.
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I realize that you have thoroughly considered the situation but many people have not, and are under the impression that you need to remove at the first sign of trouble.
Joe
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01-29-2007, 02:55 PM
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total brake failure? it just gets hard like the old cars before power. feels just like my 68 Toyoda . But I think if the parts are renewed when needed it is fine. If the pads had never be changed ever. how woud things look. The ABS parts are the same they need to be changed from time to time.
And puting on a used one is like puting used break pads..
I have to ask JoeCab what is the GM# for the front tone senders.
I know there is a GM# for the pump and Accumulator. but I have not seen the # for the senders.
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1987 black Milano Verde
1972 White spider 2000 Veloce
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