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Tried again this afternoon. I ran a full quart of DOT 3 fluid through the car, taking more than a cup from each wheel with no bubbles to speak of. The pedal still falls to the floor when engine is running to provide vacuum to power brakes.

This leads me to only one conclusion: with roughly 120k miles, this car needs a new brake master cylinder. I will look for a genuine ATE unit Monday morning. Daughter will be bummed that car is off the road for another week.

This all started because the brakes were dragging. Putting car up on jackstands revealed a locked right front caliper. Further examination revealed that RF caliper would not retract. Rears rotated fine. Left front slow but did spin. Rear caliper pistons retracted and bleed screws opened, so I replaced two front calipers with rebuilts from Performatek, as well as pads and rotors all around. Also new front rubber flex lines.

I don't see any leaks. When I press the brake with the pressure bleeder on, I can see fluid rushing from the bleeder into the reservoir, which rushes back into the bleeder when I take my foot off the brake. That can't be good.

Thanks,
Rexa
 

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Are you supposed to press the brake pedal with the pressure bleeder ON??
The instructions with the pressure bleeder does not call for one to step on the bake while the system under pressure. I don;t go higher then 10PSI.
 

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"I ran a full quart of DOT 3 fluid"

I would recommend DOT4 fluid, higher temp stuff (I use the ATE Blue, replaced by the ATE 200) for better high temperature and moisture protection, as the engine compartment of the 164 runs rather hot compared to ordinary (not so cramped) engine bays.

In years past, I had several occasions with my 91S where the ordinary DOT3 brake fluid it had come with evidently boiled in hot stop and go conditions, effectively semi-locking the brakes until I could slowly get the car moving again to run cooling air through the grill. Since changing to ATE Blue, I have had zero problems. Plus, I change the fluid every several years to get rid of any contaminants such as water, etc, to prevent corrosion.

Same goes for the clutch system. Change that fluid every several years to keep it clean and waterless. Had an occasion in my LS on a recent trip where the clutch ended up causing problems. Turns out the slave and master cylinders, and the hose, had to be changed because, while I had assumed that the fluid had been changed at a major service before I bought this used car, turns out it most likely hadn't been ever changed it appeared. The fluid in the system was really rotten, with floating corrosion flakes, really black fluid, etc. It was pretty gross. Lesson learned. If you don't know, change it.
 

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You have a failed master cylinder and perhaps vacuum booster is filling with brake fluid when you press the pedal with engine on. For ls/q car, alfa did not factory offer a master without the booster. I think you can replace the master as Long as u can set the gap between booster pin and master pin to 2 mm. Too small a gap when it gets hot it will engage, too large a gap you won't have the right pedal feel. Best course would be rebuild your current mc in my opinion.
 

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The car I am working on is daughter's 91L auto, not my 95LS. 95LS got new brake master cylinder just over a year ago so no worries there.
 

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It appears I got a bad master cylinder. I have another and will let my mechanic install and bleed it. I'm done.

I will let you all know how it comes out.
 

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Rex
PM me about latest activities of the CT and Mass. clubs.
Event this weekend in your neck of the woods.
Good luck with the R/R

Frank
 

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164B brake MC

Replacing Brake MC and have questions. The brake fluid supply hoses are 24 years old and I would like to replace them. Where can I obtain the hose? Alfa suppliers? NAPA? Rough estimate of gross length to buy? what to ask for in size (ID).

There has been discussion of "Bench Bleeding" of the MC before installation. I have bench bled before but not with a remote fluid tank. How has this been done?

Thanks in advance for all help and info.
 

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164 Brake MC

Sorry, I may not have been clear. The hoses (lines) I plan to replace are from the brake fluid tank to the Master cylinder. One comment above indicated the ID he used is 3/8. Can anyone confirm? What type of hose is used for brake fluid?

Thanks again.
 

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Discussion Starter #52 (Edited)

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Brake MC

Thank You. Hose ordered. Now costs $9.50 per meter. Sold by the meter only. Shipping to Ohio $5 so cost $14.50. Well worth it as old hose hard and cracking.
 

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Discussion Starter #55

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Well, again it is hottest day of year but I got started changing my 1991 164 12v V6 brake master cylinder 60760126.

My car is a non-ABS so there are four brake lines going to master cylinder instead of two on ABS models. Same master cylinder used on all 12v V6 164B/L/S models but L and S models have ABS so bottom two master cylinder ports are plugged on those models and two top port lines go to ABS pump and then the four brake lines go from ABS pump to brakes.

Shop manual makes it sound simple HOWEVER COMMA they fail to mention some dissassembly of engine compartment is required to even see master cylinder.

To make it easy on myself I removed the following first:

1. Air cleaner top with air flow meter and bottom including mounting support after I unbolted cruise control actuator from support.

Note models with ABS will have more brake lines running forward to pump as shown in last pictures.

2. Drained engine coolant and removed coolant tank.

3. Removed AFM inlet corragated tube from throttle body.

4. Disconnected heater hoses from engine and coolant tank tee fitting.

5. Sucked fluid out of brake reservoir with vac pump brake bleeder kit.

6. Disconnected brake reservoir from body mount and disconnected hydraulic clutch master cylinder fuild supply hose from reservoir (port blocked off on A/T models). I left supply hoses from reservoir to brake master hooked up.

7. Loosened/disconnected steel brake lines from master cylinder with 11mm brake line flare nut wrench.

8. Removed two 13mm nuts and star washers holding master to brake booster and broke vacuum by pulling on master cyllinder.

9. Removed master with reservoir and lines as one unit and retrieved vacuum booster o-ring for face of master cylinder from front of booster (Major item to account for).

10. Removed hose and elbows from old master with reservoir attached.

11. Cleaned out reservoir and hoses with brake clean spray solvent and blow dryed with compressed air hose nozzle.

12. Installed elbows, hoses and reservoir to new master cylinder and installed new brake booster sealing o-ring on face of master cylinder in machined groove. Note on ABS models install two steel plugs from old master to new master bottom two ports.

13.Reinstall master, washers and attaching nuts loosely.

14. Hooked up and clamped clutch master supply line to brake master (NA A/T models) and reclamped reservoir to body.

15. Carefully started all two or four steel brake lines (depending on non-ABS or ABS set up). Once all line flare nuts started in master cylinder ports and turn easily tighten two 13mm mounting nuts to booster and then tighten brake line nuts with 11mm wrench and finish final tightening with flare nut wrench.

16. Filled reservoir with good grade fresh brake fluid DOT 3/4 such as Castrol LMA or Pennzoil super heavy duty which has a minimum 448F boiling point and a wet boiling point of over 311F.

17. I used a Actron Europe automatic brake and clutch bleeder kit CP4062 from UK I bought from www.ipdusa.com IPD Volvo # 4062. It uses air pressure from front tire to pressurize system.

18. I bled clutch slave first since feed port of clutch is higher in reservoir than brake ports.

19. Next I bleed two front brakes and then jacked up rear body under trunk and then jacked up both rear suspesnions under trailing arm pivot points under rear struts to keep rear brake proportioning valve in weight on wheels configuration and then bleed rear brakes.

20. Reinstalled wheels and torqued lug bolts to 75 ft lbs.

21. To be continued as temp is 97 and heat index is now 105 and tomorrow is another day.

Searching through the forums for the bleeding procedure for an a/t 95 ls (so, 2 lines, not 4) and not too clear on bleeding procedure for this. Tried the usual loose fit-pedal down-tighten-pedal up and try to burp method but pedal is a bit soft. History: my grommets leak on sub zero nights. Only from the grommets so I cleaned up and reinstalled (I have to find replacements but needed to move the car out of my garage as my DD needs service and is a priority). So, I will either replace grommets or the brake master as a unit BUT I have to find clarity on the bleeding procedure for this a/t-abs model and not finding what I need. I do have a manual-pump bleeder but there are nipples on the stock master. Should I install one to make life easier?
 

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Discussion Starter #57 (Edited)
Searching through the forums for the bleeding procedure for an a/t 95 ls (so, 2 lines, not 4) and not too clear on bleeding procedure for this. Tried the usual loose fit-pedal down-tighten-pedal up and try to burp method but pedal is a bit soft. History: my grommets leak on sub zero nights. Only from the grommets so I cleaned up and reinstalled (I have to find replacements but needed to move the car out of my garage as my DD needs service and is a priority). So, I will either replace grommets or the brake master as a unit BUT I have to find clarity on the bleeding procedure for this a/t-abs model and not finding what I need. I do have a manual-pump bleeder but there are nipples on the stock master. Should I install one to make life easier?
As for A/T model or 5-speed model the brake systems are the same.

Bleeding non-ABS and ABS systems the same.


Shop manual recommends bleeding front and rear brake calipers diagonally, ie LF then RR, then RF and LR.


Using pressure bleeder such as Motive pump bottle with cap that fits master cylinder reservoir is what I use now. You just add fluid to bottle and then pump up 10-15 psi on bottle to pressurize fluid in reservoir and then open bleeder on a brake caliper to bleed air out. Front are simple but on rear calipers you need to be sure you have rear suspension jacked up under trailing arm pivot point to simulate weight on wheels to close brake valve in center of rear cross-member so fluid will flow to rear calipers.

Usually, it is easiest to leave one rear wheel on the ground and remove other wheel, put jack under pivot point under where rear strut attaches to axle to compress linkage to center cross-member valve and bled that caliper. Then install that wheel and jack up other side to compress strut and valve then bleed that side.

If you have a helper to pump up brake pedal and hold then you can still bleed brakes one caliper at a time as long as you compress opposing sides of rear suspension as you bleed rear calipers.
 

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A bit more complicated than anticipated but doable. I thought adding a bleeder nipple to one of the unused ports would be an advantage as any air would likely be in he upper line sections anyway. A job for warmer weather.
Thanks for your reply.
 

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Steve,

Now that I looked through this I see I need to bleed the clutch out first before anything. But question, I have a Motive brake bleeder kit. I have never bled a clutch before in my life. Bleeding the clutch still requires a second person to actuate the clutch pedal, right? There is no way to pressurize the clutch using the motive correct?

Also approximately how much fluid total would you think I will need (keep in mind I'm replacing all fluid in both, and all my lines are new) I think 2 bottles should cover it.
 

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Discussion Starter #60 (Edited)
Same reservoir for both. Clutch master hose outlet port pick up higher than for brakes.

You don't really have to bled clutch first before doing brakes but if you do bleed it first you then can't let fluid level go down below clutch hose port when bleeding brakes.

You can use motive pressure bottle to do the brakes, and clutch master/slave. But the slave can be a real bear to bleed all the air out.

Not easy but doable. Before your start though I suggest you check and see if your S has the dreaded "hockey puck" damper in the clutch hydraulic system. It mounts on the air cleaner support bracket. If installed remove it, disconnect two hoses from it and run the hose coming from clutch master to puck directly to slave cylinder and that will eliminate the puck and hose that originally goes from puck to slave. That rear hose should have a swivel fitting going into puck or slave if puck already removed

To get a good bleed on clutch system you almost need two people and you need to have slave off tranny and held up with bleeder as high up as hose will allow. It has a snap ring holding it in the bracket but maybe frozen in the steel mounting bracket on tranny. and you might have to remove three mounting bolts. Helps to remove air cleaner assembly to get to slave and bolts as well as puck if installed.

I did have my wife help with final bleed working/pumpingholding the clutch pedal after I got slave remounted.
 
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