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99-02 Manual Brake Help

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Old Jul 29, 2023 | 07:40 AM
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From: KCMO
Default 99-02 Manual Brake Help

I’ve converted my truck to a manual brake system using a Manual Brakes kit. At the same time I replaced my master cylinder, calipers and moved my line lock to the firewall from under the truck. I deleted my ABS many years ago as well.

im having a hard time getting a firm pedal. Originally I found that one of my fittings for my abs delete had cracked so I replaced those and now the truck stops a little better but still requires two feet to stop.

I’ve bled brakes several times and have new fluid with no bubbles. Any pointers from someone who’s done this would be greatly appreciated. Thanks for reading
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Old Jul 29, 2023 | 08:01 PM
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A pedal that is not firm but needs two feet to push is contradictory.
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Old Jul 29, 2023 | 09:06 PM
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Originally Posted by MikeGyver
A pedal that is not firm but needs two feet to push is contradictory.
Lol you’re right. What I should say is that it goes almost all the way to the floor with little to no braking but if I stand on it with both feet I can barely bring it to a stop from 30-40mph. I feel like I’m pushing on the end of the bore stroke
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Old Jul 29, 2023 | 10:03 PM
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Is it possible that the M/C piston is not coming all of the way back, like you have less than zero play in the system? I am only suggesting a common cause, I have no experience in this conversion.
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Old Jul 29, 2023 | 11:24 PM
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From: KCMO
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That could be. I’m sitting in the truck playing with the brake pedal and realizing that the brake pedal seems “tighter”. Not really sure how to explain that but it doesn’t move around as much as it did before. I used to have to pick up on it when going over bumps to keep it from kicking the cruise off.

Reading up on the problems that result from too much depth and it seems to fit the bill pretty well. I’ll try shimming it with some washers to see if it changes anything. Thanks
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Old Jul 30, 2023 | 03:32 PM
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Found a couple of washers to space the MC out where it has clearance. More than it needs but it’s still reaching the full bore stroke and it eliminates that being a possibility.

With that being said, I bled the brakes again and took it for a drive. The point that the brakes start to work has moved up in the pedal travel but is still very soft. I can’t lock the brakes up no matter how hard I press but it is stopping harder than before.

From here, I’m going to try to narrow down where my issue is by plugging the front brake side of the MC and then the back brake side. Until then I’m going to take a break from it for a few days. I’m pretty burnt out at the moment.
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Old Jul 31, 2023 | 12:36 AM
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Maybe the leak from the damaged fitting damaged the seal in the master cylinder.
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Old Jul 31, 2023 | 09:01 AM
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Originally Posted by 1FastBrick
Maybe the leak from the damaged fitting damaged the seal in the master cylinder.
Yesterday I pulled the lines and blocked both ports with plugs. The pedal was solid without any sinking. Still, I bought a new master so for peace of mind I’ll take it off and go exchange it.
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Old Jul 31, 2023 | 09:26 AM
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Do you have rear disc brakes? If so, there's nothing to keep you from having a firm pedal. If you have rear drums, they are either out of adjustment or you have the wrong M/C
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Old Jul 31, 2023 | 10:56 AM
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Originally Posted by MikeGyver
Do you have rear disc brakes? If so, there's nothing to keep you from having a firm pedal. If you have rear drums, they are either out of adjustment or you have the wrong M/C
It’s a factory disc brake truck but I put a 1320 wheels brake conversion on the rear a few years back that uses front calipers off of an OBS Chevy truck to clear the smaller wheels
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