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Ours sometimes does that when it is very cod outside. I found that starting the car and then turning it off again woke up the ARC when I restarted the car. Once driving down the road, all was ok from then on. When it is warmer out, ~40+F or more, then it works ok from the first turn of the key. Reliable enough.
 

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Discussion Starter #22
Archaeologist, I might be interested. I want to check a couple of things before I commit. Do you know of any way to test other than swap out? Is your from a Verde, or does it even matter?
Thanks.
 

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Discussion Starter #23
Del, I just tried restarting and that doesn't help. The car is in a heated (sort of) kept at about 40 degrees. When I work on it try to get it above 50.
The first time I drove it to test brakes the entire ARC lit up, along with some waning lights on the main dash, when I tried to brake hard enough to activate ABS - actually just locked up the brakes. Hasn't worked since, although the dash lights do still work. It's got me stumped, I'm guessing I fried something important in the ARC.
Thanks.
 

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Nuts. Oh well. Hope a used ARC will fix yours. These ARCs are just too sensitive to any deviations/faults, even minor ones.

Mine did the same thing but restarting the car did make it work again. I think the car has to be started and revved a little to get the juice flowing, ie, the alt starting to put out, flipping the charging circuit so that the red light would go off.
 

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All ARCs are the same except for the orange graphics on the Verde. You can swap the faces with some careful prying.
 

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Archaeologist, I might be interested. I want to check a couple of things before I commit. Do you know of any way to test other than swap out? Is your from a Verde, or does it even matter?
Thanks.
At least one of them I have is from a Platinum with ABS. I will see if I can plug it in a d see what happens. We pulled it when we converted to "racecar".

I do believe you need it for the abs to function properly. But I don't think it should affect basic brake functionality.

I also have a spare accumulator and pump, but it sounds like you're working on that.

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Discussion Starter #27 (Edited)
I machined a new adapter to use with the Mitsubishi accumulator. Here are some pictures. It doesn't seem to have solved the problem, in fact now when I turn the key the pump runs all the time. I'm assuming that means the pump is weak so I'm looking to replace it. Fingers crossed.
 

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More speculation and arm chair commentary

Firstly, good job on the adapter. Did you machine it yourself? The accumulator, with its added height due to the adapter, seems to have fit under the hood without issue. Is it a close fit?

2) I wasn't convinced of the accumulator failure diagnosis (initial problem) and less so of a problem with the pump. I've reread the entire thread and to me, the symptoms did not point to either of these components but more likely a master cylinder failure. I say this without a high degree of certainty though. You initially reported that the pump would come on for a couple of seconds on start up and not again until the pedal was depressed several time (number not stated). Your initial complaint was, with increasing pedal force, poor braking, then a kick-back, and then full braking resulting in lock up. Mark_toro also reported a kick-back symptom albeit with less severe symptoms. These master cylinders are quite complex with multiple passages, several piston/cylinders, valves, and many seals. I'm going to theorize that these symptoms(between you and Mark) are related and caused by a bad/leaking seal inside the MC that causes the kick-back(from a properly pressurized and working pump/accumulator) through an undesirable hydraulic path. Else, where would the force come from to kick-back the mechanical force applied by your leg?

3)So why the step backward with the new accumulator? Dunno. Is there air on the hydraulic side of the diaphragm of the accumulator ? How did you go about bleeding the system when the accumulator was replaced?
 

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Nice job on the adapter. Bummer that the pump runs all the time. Have you confirmed that there is brake fluid at the pump inlet? Checked the pressure switch? I never had to bleed the system after an accumulator swap.

What are the threads on the Mitsu accumulator? Knowing that information will allow me to copy your adapter w/o buying a new accumulator, making for a much faster swap in the future.

Thanks
Mark
 

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Discussion Starter #30
Firstly, good job on the adapter. Did you machine it yourself? The accumulator, with its added height due to the adapter, seems to have fit under the hood without issue. Is it a close fit?

2) I wasn't convinced of the accumulator failure diagnosis (initial problem) and less so of a problem with the pump. I've reread the entire thread and to me, the symptoms did not point to either of these components but more likely a master cylinder failure. I say this without a high degree of certainty though. You initially reported that the pump would come on for a couple of seconds on start up and not again until the pedal was depressed several time (number not stated). Your initial complaint was, with increasing pedal force, poor braking, then a kick-back, and then full braking resulting in lock up. Mark_toro also reported a kick-back symptom albeit with less severe symptoms. These master cylinders are quite complex with multiple passages, several piston/cylinders, valves, and many seals. I'm going to theorize that these symptoms(between you and Mark) are related and caused by a bad/leaking seal inside the MC that causes the kick-back(from a properly pressurized and working pump/accumulator) through an undesirable hydraulic path. Else, where would the force come from to kick-back the mechanical force applied by your leg?

3)So why the step backward with the new accumulator? Dunno. Is there air on the hydraulic side of the diaphragm of the accumulator ? How did you go about bleeding the system when the accumulator was replaced?
I did machine the adapter myself, kind of proud of it. It does fit under the hood but is a close fit. I haven't tried to measure clearance after installation, but before I made the adapter I was able to verify about an inch of clearance with the stock accumulator and my adapter adds about 3/4". I will probably try to move the pump/accumulator assembly mounting down a bit.

I'm hoping it's not the MC, I haven't seen a new or rebuilt one, or even a rebuild kit for sale. I'm thinking that since the brakes were steady but ineffective with ABS disabled that the MC is OK, but I'm not sure what effect the inoperative ABS system might have.

With the problem I had with the new accumulator I believed that there could be a problem with my adapter so I reinstalled the old accumulator and it's doing the same, continued running after turning the key. I suspect, as you suggest, that bleeding the brakes may resolve the problem. At least I hope so. I haven't been able to bleed the brakes yet because, per the workshop manual, it requires 2 people. I expect to get that done today and will report back.
 

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Discussion Starter #31
Nice job on the adapter. Bummer that the pump runs all the time. Have you confirmed that there is brake fluid at the pump inlet? Checked the pressure switch? I never had to bleed the system after an accumulator swap.

What are the threads on the Mitsu accumulator? Knowing that information will allow me to copy your adapter w/o buying a new accumulator, making for a much faster swap in the future.

Thanks
Mark
Mark,
The threads on the Mitsubishi accumulator are 16mm x 1, on the Milano accumulator are 14 x 1.5. The tap and die can both be fairly expensive but I found both on eBay and Amazon for about $10 apiece in HSS. I wouldn't want to use them in a professional shop but they worked fine for one use.

I had to make a change after taking the pictures as I forgot to machine a bevel at the top of the female threads for the o-ring.
You have to machine a groove for the o-ring on the male threads also.

I used 1-1/4" 303 stainless rod - easier to cut than 304 or other stainless - from Metal Supermarkets. I'm not sure it needs to be that big around but I don't have the skills to determine the requirements for 185 BAR so opted for overkill.

Another thing I didn't do because I can't see a purpose is to drill a hole in the adapter threads to match the one in the original accumulator. There is not a matching channel or opening inside of the pump threads, so I assume that it had some purpose in another application.
 

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If you did not drill the hole in the adapter make **** sure that you unscrew the accumulator first. The little hole is a pressure relief safety. Think like the lid on a 2 liter bottle of pop. Allows the Fshhhh... and keeps the lid from shooting off. Imagine that with 100s of Bar! Accumulator rocket!

Of course 25 pumps until the pedal goes hard discharges the pressure, but wouldn't want to make the mistake of unscrewing the adapter under pressure w/o the hole.

Thanks for the thread specifications!

Mark
 

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This why I am in process of swapping out my ABS for conventional brakes. My Verde had been apart for some time and I don't want to deal with it all. The accumulator was weak when I took it apart..

Dom


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Discussion Starter #34
Thanks for the info on the hole in the accumulator threads. The Mitsubishi accumulator doesn't have that hole either so I will probably have to add to it and the adapter. Or maybe just make a permanent sticker to attach to the accumulator and/or adapter.

I bled the brakes and I'm now getting fairly normal behavior from the brakes, although they still seem kind of soft. I may drive it a bit and then bleed the brakes again. At least the car is driveable now. I'm still in search of a replacement pump just in case. Or even better a non-ABS conversion.

If I make any further progress I'll post it here.

Still have a nonfunctioning ARC. Will probably start a new thread for that problem.

Thanks to all for all of you help!
 

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Discussion Starter #35
This why I am in process of swapping out my ABS for conventional brakes. My Verde had been apart for some time and I don't want to deal with it all. The accumulator was weak when I took it apart..

Dom


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Dom,
Is there a thread anywhere on the BB with details for making the swap? What pieces are needed and where did you get them?

Thanks.
 

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I machined a new adapter to use with the Mitsubishi accumulator. Here are some pictures. It doesn't seem to have solved the problem, in fact now when I turn the key the pump runs all the time. I'm assuming that means the pump is weak so I'm looking to replace it. Fingers crossed.
What are the two thread sizes on the adapter? Too bad the accumulator didn't fix it
 

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I am not sure of where the thread is honestly. I know that there is one and I will need to find it once I dig into the ARC end of things to disable the red alert.

Off the top of my head: You need a new pedal box to mount the conventional master cylinder, brake booster, master cylinder and reservoir, the proportioning valve and new lines to the front wheels. Someone will let us know if I missed something.

I know APE has a conversion kit but I found all the parts from members/classifieds here. I took my time and accumulated (pun intended) the different pieces slowly.

Another tip I got from Zamani was to use a 164 master cylinder since it is a little larger for more braking power. The 164 MC i got has a remote reservoir so I have to work through that. Also I plan on getting an adjustable brake proportioning from Summit since I don't have the inline stock one.

DOM!

Dom,
Is there a thread anywhere on the BB with details for making the swap? What pieces are needed and where did you get them?

Thanks.
 

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Discussion Starter #38
What are the two thread sizes on the adapter? Too bad the accumulator didn't fix it
All the information I have,including material used, is in post 31 above. There are pictures in post 27.
The accumulator was a big improvement, to the point that I can drive the car. Now that the system is functioning basically as it is supposed to I'm going to focus on the pump. Then I think I just need to go through everything brake related and fine tune, including another brake bleed in a week or so.
 

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All the information I have,including material used, is in post 31 above. There are pictures in post 27.
The accumulator was a big improvement, to the point that I can drive the car. Now that the system is functioning basically as it is supposed to I'm going to focus on the pump. Then I think I just need to go through everything brake related and fine tune, including another brake bleed in a week or so.
From what I remember the brakes don't feel great when they work properly.

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I actually prefer the feel of the ABS brake system in the Milano over the softer pedal in the GTV6. Both systems are up to snuff. Residual pressure valves have been recommended to firm up the GTV6, but haven't taken that step.

Glad your brakes are functional - so far (3 years / 70Kmiles) mine have been reasonably reliable once I got them working.
 
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