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Newbie - Soft Brake Pedal

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J

John Kuzman

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Greetings!
I recently took title to a '59 Bugeye (BE). The BE had been sitting for about two years. While driving the BE off the trailer, I noticed the brakes were not the best (firm pedal, but poor stopping power). After sitting for a few days, I noticed brake fluid near the RF tire. Pulled the RF drum and had soaked shoes.
I decided to re-build the front brakes. Installed new wheel cylinders, shoes and flexible hoses. Had the drums turned to within spec for max. diameter.
Bled the system using the two-person pump, hold, bleed method. Started RR, then LR, RF and LF. Each wheel several times. Using DOT 3 fluid. Bled about 12-14 oz. of fluid.
Pedal is soft. If pumped two or three times, it firms up, but still feels somewhat soft and fades with continued hard foot pressure.
Do I still have air in the system? If I have a leak that is drawing air in, how do I find the leak? I have gone back and tightened down all connections. Thanks, I would truly appreciate any advice at this point.
John
 
Sounds like the master cylinder may have some "bleed by". Have you examined it for leaks?
 
TJ-
Hello Louisville! I have been to the June British Car Show in Louisville 3-4 times over the years. I enjoy the new venue near the RR tracks. Easy drive from Cincinnati.
I am not seeing any external leaking from the MC. The amount of fluid bled through the system is consistent with the amount I need to add to the MC after a few pumps and bleeds.
 
The show is going to be in the same place this year, with events on Friday night as well. If the weather cooperates this year should be the best ever. I'm trying to get more spridgets to the show. Any chance of getting the bugeye here?
Anyway, Does the pedal get softer with each "pump up"? It seems like you have check everything except the master cylinder. If all the wheel cylinders are staying dry and you've checked all the junctions, then a MC rebuild kit may be worth a try. I'm not familiar with the combo units, but I'm sure someone else will be along to help out.
 
TJ-
Thanks for your responses. Before I go the MC route, I am going to try and fabricate an adapter and use my pressure bleeder on the system. If I can successfully bleed my '69 Corvette with the pressure bleeder, (C3 Vettes are notorious for sucking air into the system) it should work here.
If that fails, then I guess it is MC time.
I doubt that the BE will be totally roadworthy for Louisville in June. Maybe my "other" Healey, BJ7, the vette, or just the traditional, albeit boring transportation. Probably just drive down to St. Joseph School Saturday morning.
John
 
I agree. If everything else checks out then I woule consider the MC. I went through the same thing on my car. Slowly replacing all the little stuff when in the back of my mind I knew it was the MC but didn't want to admit it. Long story short, I finally rebuilt the MC and it cured all my problems. My MG stops harder than any car I've ever owned.

JACK
 
Thanks Jack. If I do eventually accept the fact that I need to address the MC, should I just buy a kit from one of the usual vendors, or ship the MC off for a complete re-build at nearly $200.00 (it is the dual brake/clutch MC). If I should send it out for the re-build, does anyone have any experience or recommendations on a vendor? Thanks in advance.
John
 
[ QUOTE ]

Pedal is soft. If pumped two or three times, it firms up, but still feels somewhat soft and fades with continued hard foot pressure.
Do I still have air in the system? If I have a leak that is drawing air in, how do I find the leak? I have gone back and tightened down all connections. Thanks, I would truly appreciate any advice at this point.
John

[/ QUOTE ]
The fact that the pedal firms up "might" indicate that there is still air in the system. There is a residual pressure valve that is intended to keep a slight pressure on the system even when the brakes are not operated. This pressure, typically 2 psi for discs, 10 psi for drums, prevents drawing air back into the system past the wheel piston seals when the brakes are released. There is a slim chance that the residual pressure valve is not working.

The fact that the pedal fades would indicate that fluid is bypassing the master cylinder piston seals & they need to be replaced. Maybe two problems? The master cylinder needs to be fixed first. It might cure both problems.
D
 
Dave:
Thanks for the advice. Would you opine on whether I could just do a rebuild using one of the vendor rebuild kits at under $20, or if I need to send the MC off for a total rebuild at $200. Also, any experience, or recommendation on a rebuilder. Thanks.
 
Hi John,
If your cylinder is not rusted or pitted inside the bore, you should be able to rebuild it. If it IS rusted, you could have it re-sleeved inside. There are probably several places to get it resleeved. White Post is a good place. Check them out:
https://www.whitepost.com/
D
 
Dave:
Last question (for today), I promise, do I need to remove the MC from the car to install a re-build kit? The Workshop Manual seems to suggest that the re-build is done by simply removing the end plate and withdrawing the piston and related washers and seals. Thanks.
 
John,
I don't see how you could possibly do it right without removing it. Everything must be cleaned with a non-petroleum solvent, carefully inspected, lubed with brake fluid, & re-assembled. I'm not sure how you could even determine bore condition with it still in the car. Bore condition is THE most important factor in a successful rebuild. Maybe this was how it was rebuilt the last time.
D
 
I think you should rebuild the unit yourself.
All that you will be doing is taking the 6 or 7 parts out, cleaning them in brake cleaner, putting the unit back together with the new parts, and you are done. You'll get to clean up the parts and the area where the parts are sitting, get to know the car better, etc etc.
Sometimes they need a light honing, the hones don't cost too much from a tool store or pep boys, etc.
If you need an opinion, you can always take it to a British shop in the area; they usually are helpful, they know you'll be a customer some day.
Lou
'59 Bugeye owner for 30+ years
 
Lou,
Thanks for the reply. Within the last few days, I adapted my pressure bleeder to fit the BE. Pressure bled the system last night. New development: leaking left, rear cylinder. I think it may have been weeping before, but I just noticed the fluid last night, and when I pulled the rear drum, the shoes were soaked!!!
Game plan: Rebuild the ENTIRE system. I had only rebuilt the front earlier. I should have realized that the car may have sat idle for an extended period of time and the whole system was suspect.
I ordered the rear cylinders, shoes and hose, and a kit for the master. The Workshop directs you to remove the backing plate and brake components as a unit after disconnecting the handbrake and brake line. Is this the way to proceed on the rear?
John
 
Re: Newbie - Soft Brake Pedal - UPDATE

Well, after bleeding the entire system at least ten times, and installing a master cylinder re-build kit, I finally accepted the truth...time for a master cylinder re-sleeve.
Pulled the MC last Friday evening. Shipped to White Post Sat. morning. They returned the MC to me for Wed. delivery!! Re-installed Friday night. I've got brakes!!! The clutch is not dis-engaging to my satisfaction (I have to double clutch from first to second), but I may still have some air in that part of the system.
Thanks to all for your guidance. A little plug for White Post Restorations: Billy and W.R. are first-class, great people. they turned around my MC in record time without gouging me for the prompt service.
John
AN5, BJ7
 
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