How to fix Geo Master cylinder and power booster brakes

2012 ALL OTHER MAKES ALL OTHER MODELS
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JDKOSKELA
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I recently just finished building a trike but am having troubles with the brakes. They work but take much too long to slow down/stop suddenly. They don't seem to be locking. I tried both the front and rear port of the master cylinder which made no difference. Should I try bleeding the brakes again? If you have any ideas I'd appreciate it.

If you need specs:
Rear end: Model 200 Nissan
Brakes: Geo master cylinder and power booster
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Dec 29, 2011 at 6:48 PM
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FIXITMR
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is it disc brakes?
Dec 29, 2011 at 6:51 PM
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CJ MEDEVAC
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USING ONLY ONE PORT OF THE MASTER CYLINDER?

BOTH SIDES FULL OF FLUID?

IS THE OTHER PLUGGED OFF?

IF PLUGGED, MAYBE THAT PORT IS BUILDING PRESSURE INSTANTLY--AND NOT ALLOWING THE PISTON TO TRAVEL FURTHER TO MOVE FLUID IN THE OTHER RESERVOIR

JUST THROWING CRAP---I'VE NEVER USED ONLY HALF OF A MASTER CYLINDER

TIE 'EM/ TEE 'EM TOGETHER?

PUMP ONE SIDE DRY AND LEAVE IT UNPLUGGED?

USE A SINGLE RESERVOIR MASTER CYLINDER AS MY 1946 WILLYS JEEP USES?

MAYBE SOMETHING I SUGGESTED WILL HELP OR SPARK AN IDEA

THE MEDIC

Dec 29, 2011 at 9:13 PM
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FIXITMR
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tee them together was a thought i also had. got enough vaccum to booster? does pedal feel right? aint no proportioning valve inline some where? did you actually look at brake parts in wheels?
Dec 29, 2011 at 10:09 PM
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JDKOSKELA
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Yes they are disc brakes and one side is plugged and the other runs to the rear brakes. No proportioning valve inline.

How do you test vacuum to the booster, I just have vacuum in hose.

Teeing them together sounds like a good idea, do you think it would work without a proportioning valve?
Yes and brakes look good, they just take a long time to slow down and the pedal pushes in further than expected.
Dec 30, 2011 at 2:03 AM
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CADIEMAN
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remove the hose on the booster check for vacuum.if the front is running on handle bar master.youll need to install a 1 port master that has the same hook ups and specs. as oe.if you want the booster. it has to have everything that was on the orignal sys.
Dec 30, 2011 at 2:27 AM
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FIXITMR
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that's what i was assuming original handelbar front brakes?
Dec 30, 2011 at 5:55 AM
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JDKOSKELA
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Yes the original handlebars front brakes are fine.

If the master cylinder is lower than the calipers, would that make a difference in the movement of fluid and brake performance?
Dec 30, 2011 at 6:48 PM
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FIXITMR
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interesting question? i would guess NO.
Dec 30, 2011 at 8:59 PM
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JDKOSKELA
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Thank you all for your responses I've been trying all the advice you've given me with no luck so far but if I have any more questions I'll post them here. Hope you like the trike I'll add a few more pictures for you.
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Dec 31, 2011 at 12:33 AM
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FIXITMR
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will teeing together give twice the hydraulic pressure? is caliper piston size relavent to master cylinder bore diameter? dos booster feel like it is functioning ok?
Dec 31, 2011 at 1:13 AM
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CADIEMAN
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whats the vacuum reading at the booster line??????its obvice your not getting any brake assist.hard pedal right.ty for using 2carpros
Dec 31, 2011 at 6:22 PM
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JDKOSKELA
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I teed the lines together and it seems to be working just fine thank you for all your help!
Dec 31, 2011 at 7:27 PM
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CJ MEDEVAC
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MY GOSH CJ MEDEVAC....YOU ARE A GENIOUS!!!!!

GLAD YOU GOT IT WORKIN'

THE MEDIC
Dec 31, 2011 at 7:34 PM
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CADIEMAN
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GLAD U FIXED IT.HAPPY NEW YEAR P/S NICE TOY
Dec 31, 2011 at 8:29 PM