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Old 12-27-2016, 06:40 PM   #1
6768chevylover
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brakes......

Okay let me tell you what I'm experiencing.. Every once in a while when I come to a stop I feel like I have manual drum brakes(if you understand that).. I have a 71 blazer with power brakes. Everything is new for brake oriented except for booster and proportioning valve. The calipers are the wildwood replacement calipers... Like I said it seems when I come to a stop it seems to keep rolling even if I press on the pedal harder.. Scares me sometimes. Any Ideas what it might be? Thanks, Mike Happy Holidays!
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Old 12-27-2016, 10:04 PM   #2
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Re: brakes......

Check you vacuum line. Sound like you are loosing vacuum
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Old 01-09-2017, 04:15 AM   #3
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Re: brakes......

Quote:
Originally Posted by 6768chevylover View Post
Okay let me tell you what I'm experiencing.. Every once in a while when I come to a stop I feel like I have manual drum brakes(if you understand that).. I have a 71 blazer with power brakes. Everything is new for brake oriented except for booster and proportioning valve. The calipers are the wildwood replacement calipers... Like I said it seems when I come to a stop it seems to keep rolling even if I press on the pedal harder.. Scares me sometimes. Any Ideas what it might be? Thanks, Mike Happy Holidays!
I too experience this. I replaced soft lines, master cylinder, wheel cylinders, calipers, and pads. Still happens but only rarely.

I find it usually helps to find a clear spot and hit the brakes hard. My brakes usually feel much lighter and more responsive after this.
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Old 01-09-2017, 10:40 AM   #4
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Re: brakes......

That's the problem when mixing components. You say you're using Wilwood calipers that are a direct replacement, but did you check the piston surface area compared to your original pistons to make sure they were the same? That would be the first thing to do IMO. You may need to increase or decrease the bore of the master cylinder to suit those calipers.
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Old 01-09-2017, 02:00 PM   #5
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Re: brakes......

Check you vacuum. Low manifold vacuum, leaky one way valve, leaky diaphragm, will all cause that.
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Old 01-09-2017, 02:43 PM   #6
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Re: brakes......

I had to add a vacuum reservoir when I changed my cam to have more boost. Then I went to Hydroboost. Much better now.
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Old 01-09-2017, 02:54 PM   #7
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Re: brakes......

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I had to add a vacuum reservoir when I changed my cam to have more boost. Then I went to Hydroboost. Much better now.
I too used a vacuum reservoir with my low vac cam. Worked OK. Then I too went to Hydroboost. Absolutely the best brake mod out there.
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Old 01-09-2017, 03:07 PM   #8
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Re: brakes......

Dragging a trailer, it's the ONLY way to go
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Old 01-09-2017, 03:13 PM   #9
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Re: brakes......

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Dragging a trailer, it's the ONLY way to go
No doubt. That's the main reason I went Hydro.
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Old 01-09-2017, 04:16 PM   #10
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Re: brakes......

did yas make your own hydro or did ya buy the kit?
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Old 01-09-2017, 05:43 PM   #11
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Re: brakes......

I bought whatever goes to a 1-ton and made it work.
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Old 01-11-2017, 10:40 AM   #12
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Re: brakes......

Did you use your MC that was on the blazer or what you ordered?
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Old 01-11-2017, 10:47 AM   #13
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Re: brakes......

I was able to use what was on the Blazer. In fact, I didn't have to crack a line or bleed the brakes.
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Old 01-20-2017, 09:57 PM   #14
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Re: brakes......

Does it matter what type of booster ,Delco or bendix to use with a MC? Will a Delco mount to a bendix bracket?
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Old 01-24-2017, 10:07 AM   #15
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Re: brakes......

I was experiencing a similar problem with braking and after reading various threads, I went to Advance auto.com and ordered a K3500 brake booster for $70. I reused the original MC shaft as instructed in the thread and it has made a huge difference.

You can find the exact same part at Rock Auto, but Advance seemed to have the best price. I used my Cadmium finish kit from Eastwood, for the look I prefer. I believe the booster also came black from the factory, but it is so prominent in the engine bay that I went with cadmium.
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Old 01-24-2017, 11:04 AM   #16
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Re: brakes......

Quote:
Originally Posted by 6768chevylover View Post
Does it matter what type of booster ,Delco or bendix to use with a MC? Will a Delco mount to a bendix bracket?
Most of these are pretty interchangeable. I would bet that you'll have no problem. I'm using an aftermarket booster (Tuff Stuff) on the factory bracket with an 03 MC, and everything fit together perfectly.
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Old 01-24-2017, 12:12 PM   #17
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Re: brakes......

buckkoo what year was the booster? It mounted to the power brake bracket?
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Old 01-25-2017, 02:46 PM   #18
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Re: brakes......

http://67-72chevytrucks.com/vboard/s...d.php?t=456859

I did this - helped a lot.
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Old 01-26-2017, 01:53 PM   #19
6768chevylover
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Re: brakes......

Ochre did you already have the delco brake booster mount for yours? I have a bendix booster mount. I guess I need to find a delco one..
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Old 01-26-2017, 01:57 PM   #20
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Re: brakes......

What's the difference betwen the two?
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Old 01-26-2017, 02:08 PM   #21
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Re: brakes......

I used a 1972 K3500 Booster.
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Old 01-26-2017, 02:28 PM   #22
6768chevylover
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Re: brakes......

apparently the mounting pattern. I believe the delco booster is a tad bit wider then the bendix..
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Old 01-26-2017, 04:14 PM   #23
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Re: brakes......

Not bolt pattern? Mine has 2 unused holes at the bottom and I can't remember if I had to drill any.
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Old 01-26-2017, 04:40 PM   #24
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Re: brakes......

can't say that I know what I have or what the difference is. It was the existing factory mount and the new 1 ton unit fit. The brace that goes under the booster and connects down lower on the firewall ends up being maybe an inch or so short, but playing around with the angle a little bit and a few washers here or there and it's pretty easy to get it to work.
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Old 01-26-2017, 04:51 PM   #25
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Re: brakes......

just loosen the bolts where the bracket mounts to the firewall to accommodate for minor difference in booster bolt spacing
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