bleedin' brakes

[crispy]

Hello Everyone,

I was helping my neighbor bleed his brakes on his 1980 MG (don't ask). I have been having a heckuva time get the air out. Been working on one wheel for about 20 minutes and still getting bubbles. I don't see any leaks and cant figure out if any air is getting into the system. any ideas? the system is similar to my roadster and I have never run into this problem when bleeding mine. Thanks for any help.

Cris

[Import_sounds-of-mid-GA]

sounds to ME like the master cylinder grommets/seals are bad and are letting air in...

[spl310]

I used to struggle with bleeding brakes, but I built a pressure bleeder. WOW!! That is the only way to go!! Now, someone out there is a dealer for the powermotive bleeders and he offered a sweet deal to the list a while back. Since I purposely limit my Roadster budget to almost nothing, I opted to build my own. I researched and found this link:

http://www.bmw-m.net/TechProc/bleeder.htm


I did not add the pressure gauge nor the valve to release the pressure. They are easy add ons though. I used an old Roadster m/c cap and did one thing differently. I used a fitting which went down into the m/c. The thought behind that is that it would not fill above that level so when you pull the cap off, it does not slobber over. It seemed to work FANTASTIC! It takes more time getting up and down to get under the car than it actually does bleeding the brakes. Rock solid pedal too!

YMMV, Batteries not included, some assembly required, not available in states where restricted or taxed, yadda, yadda, yadda...

[Brad Lustig]

You aren't using a vacuum bleeder by any chance, are you? With the vac, air seeps in around the threads of the valve and makes it look like air is still in the system. One way to control that if you still want to try the vac bleeder, wrap teflon tape around the threads and reinsert the valve. I really suggest that you switch over to a pressure bleeder. That's the only way to go. I made one out of an old garden sprayer, too. Also, make sure all of your lines are tight and rubber hoses are new. Even a solid looking rubber hose can fail if it's got some age on it. And it doesn't always show itself as the culprit.

[shifty]

Sid, that link rocks!

I have a Motive (which cost a bit more than $20!). Once I learned how to use it, I've been pretty happy with it, other than the mess of removing it.

Think I'll modify a roadster cylinder cap with the extra bit of hose - hopefully no more mess!

[spl310]

Leigh,

Glad you liked it! I found that with my garden variety pressure bleeder (pun intended), I can release the pressure by very slowly unscrewing the pump. Once it starts venting, just leave it alone, and the need for a bleed valve is gone. I don't put much pressure - not much is needed - so no need for the gauge in my opinion. The cap was simple, but there is a warning I forgot to add. Get some tie wraps. Use them to hold the cap down on the master cylinder. It may not be needed, but I don't like the idea of pressurized brake fluid launching the cap and spraying the paint work...

Like I said in the earlier post. It was a fantastic way to bleed the brakes!

[spl310]

I just checked the link and see that he has added the info on extending the nipple below the cap. I did that with the fittings, so there was no need for JB weld or any other such nonesense. Just spent a little time at the Ace Hardware looking for the right brass pieces.

All in all, it was quite a fun adventure building the unit!

[Half Fast Racing]

Group/List/Forum.........

I am the Motive Power brake bleeder dealer on the Datsun list.
I haven't offered a Datsun list group buy in a couple years,
so now may be a good time......?

If there is interest from this forum,
in the next couple days ?????
I'll post a direct link to a web page for the line of Motive Power brake bleeders with discount pricing
for Datsun forum/mailing list members,
plus I'll offer free shipping for this deal..........

Got to keep those roadsters on the road !

Let me know if there is interest.

[dbrick]

With the Motive, turn it upside down when you are done and let it push air into the reservior as you bleed the last bit of fluid out, until fluid is at normal level. No mess on removal. I have one, crude and messy, but works GREAT. Quick connects on the hose would be nice.

Also, poor mans pressure bleeder, a pain but it works. Take a bicycle inner tube, chop out the section with the valve and a few inches either side.Roll and glue one end closed. Fill the Master cylinder, hose clamp the tube to the top of the reservior and pump in a few pounds of air with a bike pump. Watch the fluid level and pump a bit more air when needed. have to remove it to refill, but hey, it cost $1.50. Ain't pretty, but it works.

[shifty]

John,

Is there a better cap (the part that fits on the master cylinder) to fit the roadster? I had to cut off part of the cap to use it for the clutch master and the rear brakes, but it won't fit on the front brake reservoir.

Something more like the actual cap?

[dbrick]

John,

Is there a better cap (the part that fits on the master cylinder) to fit the roadster? I had to cut off part of the cap to use it for the clutch master and the rear brakes, but it won't fit on the front brake reservoir.

Something more like the actual cap?

That was the problem I had, just too big and clunky to get into place.

[Half Fast Racing]

The universal bleeder cap is the only one that works with the roadsters.
And with all the variances and big tolerances in roadster construction,
the same cap will fit some roadsters and not others, especially where it has to fit up against the notched firewall.

The European cars have a screw-on master cylinder lid and Motive Power
makes a screw on bleeder cap that works like a charm, too bad this isn't the case on our roadsters.

Here's a trick I use on my MR2s. Took an old master cylinder cap, assemble a hose barb that penetrates down through the old master cylinder cap, hook it to the Motive Power Bleeder and I have a home made custom bleeder lid that fits all out MR2s (6 at last count....)
To avoid any unwanted mess, I tighten a big hose clamp to make sure the custom bleeder cap stays ON the master cylinder when I pressurize and bleed.

I'm pretty sure the same trick would work for a roadster master cylinder cap. I'll need to experiment one of these days.

[Brad Lustig]

Any chance of using a beaker stopper like these?



I don't know if they would seal correctly or if they would hold enough pressure. Something I was going to try.

[spl310]

I had a few old Roadster master cylinders lying about, so I took one of the plastic caps, put a couple of fittings on it (with washers to allow good compression) and held it onto the master cylinder with a HUGE tie wrap. Worked like a charm and was super cheap. I only had to buy a couple of fittings at ACE Hardware for maybe a buck and a half each...

[dbrick]

I'm going to try Sids's method..I have some giant reusable tiewraps.