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initiator
12-27-2017, 03:42 PM
Has anyone successfully rigged a pressure bleed cap for the FF polished reservoirs? I don't want to spend more $ on the CNC reservoirs. I could buy another reservoir and mod the cap, but that seems like a waste.

Thanks for any help.

Joe

Papa
12-27-2017, 03:51 PM
Motive Products makes caps for many different size master cylinders.

https://www.amazon.com/s/ref=nb_sb_noss?url=search-alias%3Daps&field-keywords=motive+bleeder+cap&rh=i%3Aaps%2Ck%3Amotive+bleeder+cap&ajr=0

phileas_fogg
12-27-2017, 06:07 PM
You don't need much pressure; 5 psi will get the job done & certainly less than 10. A bicycle inner tube knotted at one end and slipped over the reservoir body would work. Pump up the tube just enough to make it resist hand pressure and you're good to go. Be sure to check the reservoir fluid level to keep it from running dry.


John

grluisi150
12-27-2017, 07:15 PM
I purchased a rubber stopper from McMaster carr https://www.mcmaster.com/#rubber/=1aver9c
Gary

initiator
12-27-2017, 08:05 PM
John - A combination seal and bladder at the same time! Sounds like a plan.

Papa - I went through the Motive adapters in some detail, but couldn't find any that seemed to match the FF reservoir cap. Probably their universal adapter would work, as it just makes a face seal on the reservoir top.

initiator
12-27-2017, 08:26 PM
Working off Gary's idea, I found size 6 1/2 Rubber Tapered Round Plugs at McMaster with one hole. I plan to widen the hole a bit and silicone a quick-disconnect in there for my compressor to attach to. 5 psi isn't much, but I figure the plug will pop out if the pressure gets too high.

Note that I used Size 10 of these same plugs to anchor the e-brake cables in the differential housing 'ears'.

Thanks for the quick feedback!

Papa
12-27-2017, 08:30 PM
Working off Gary's idea, I found size 6 1/2 Rubber Tapered Round Plugs at McMaster with one hole. I plan to widen the hole a bit and silicone a quick-disconnect in there for my compressor to attach to. 5 psi isn't much, but I figure the plug will pop out if the pressure gets too high.

Note that I used Size 10 of these same plugs to anchor the e-brake cables in the differential housing 'ears'.

Thanks for the quick feedback!

Don't connect it to your compressor! Just use a bicycle pump. Trust me.

Dave

Ducky2009
12-27-2017, 10:04 PM
..... I don't want to spend more $ on the CNC reservoirs. I could buy another reservoir and mod the cap, but that seems like a waste.

Joe,
Are you planning on adding a second FF brake reservoir? I have one you can have, just pay for shipping. I used a vacuum bleeder.
PM me .
David

CraigS
12-28-2017, 08:01 AM
When I was making up my pressure bleeder for my CNC MCs I talked to CNC. They strongly recommend a max of 5# pressure. They also strongly advised me to be sure I did not move the brake pedal while I had pressure on the MC.
I started w/ a piece of radiator hose that would slip over the top of the reservoir and then went to the plumbing section at Ace.
https://farm5.staticflickr.com/4588/39320475642_8b0a91d4fd_c.jpg (https://flic.kr/p/22UBHvd)Pressure Bleeder (https://flic.kr/p/22UBHvd) by craig stuard (https://www.flickr.com/photos/152454123@N04/), on Flickr

flynntuna
12-28-2017, 02:07 PM
I love that home made tool.:cool: simple , practical and cheap.

initiator
12-29-2017, 03:36 PM
Greatly appreciate all the feedback and support. I'm constantly amazed at the different creative approaches folks use to overcome obstacles.

David - PM sent.

Papa - You're concerned about the compressor supplying too much pressure? I could mount a Shrader valve just as easily as a QD and have my son man the pump while I crack the fittings.

Craig - Thanks for the extra tip about not moving the brake pedal while pressure is on. Hadn't thought that far ahead and might have done it without thinking.

Papa
12-29-2017, 05:39 PM
Greatly appreciate all the feedback and support. I'm constantly amazed at the different creative approaches folks use to overcome obstacles.

David - PM sent.

Papa - You're concerned about the compressor supplying too much pressure? I could mount a Shrader valve just as easily as a QD and have my son man the pump while I crack the fittings.

Craig - Thanks for the extra tip about not moving the brake pedal while pressure is on. Hadn't thought that far ahead and might have done it without thinking.

Exactly! Trust me, I learned the hard way. You only need a few pumps with a bicycle pump to bleed each caliper.

Dave

jwebb
12-30-2017, 08:10 AM
Pressurizing the MC to bleed the brakes instead of pumping the brake pedal?

BB767
12-30-2017, 09:26 AM
Pressurizing the MC to bleed the brakes instead of pumping the brake pedal?

The master cylinder reservoirs to be exact. It was the ONLY way I could get all the air out of my lines after trying for two days to do it other ways! For some reason the Wilwood cylinders admit air (around the piston I am assuming) when trying to bleed the conventional way.

jwebb
12-30-2017, 10:27 AM
The master cylinder reservoirs to be exact. It was the ONLY way I could get all the air out of my lines after trying for two days to do it other ways! For some reason the Wilwood cylinders admit air (around the piston I am assuming) when trying to bleed the conventional way.

Probably why I'm having trouble with my brakes

Papa
12-30-2017, 10:34 AM
Probably why I'm having trouble with my brakes

If you haven't already done it, you'll want to bench bleed the master cylinders before you start working at the calipers. It's easy to do with the masters mounted in the car. Just attach a piece of tubing from the "out" port on the master cylinder and run it to the reservoir. Pump the brake pedal to cycle fluid through the master until you don't have any air bubbles. Reconnect your brake line and then bleed the calipers.

jwebb
01-08-2018, 12:48 PM
If you haven't already done it, you'll want to bench bleed the master cylinders before you start working at the calipers. It's easy to do with the masters mounted in the car. Just attach a piece of tubing from the "out" port on the master cylinder and run it to the reservoir. Pump the brake pedal to cycle fluid through the master until you don't have any air bubbles. Reconnect your brake line and then bleed the calipers.

I haven't tried this yet but I think it will work!!

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