Braking power not what it could be on an old van.....

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Braking power not what it could be on an old van.....

Post by oldsmoker »

So, what i notice is that when im on I95 and I need to slow down quickly, there is not a great feeling of confidence about my ability to stop in a hurry.

Im pressing the pedal but it seams that more could be happening. I know that the rear brakes are in good shape. The front rotors and pads are also good. the only thing that I would like to change is the front brake lines from the calipers, when i do , ill get braided hoses but i dont think these make that much difference, right?

So after that, im onto the master cylinder and booster?...what is there on/in these parts to go bad with age?

I see posts about upgrading front calipers to bigger ones, but surely a standard system working properly is a good start!

any input appreciated, many thanks!.
1989 Astro 4.3 283k. Originally a Zimmer conversion van, now a stripped out cargo.
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Re: Braking power not what it could be on an old van.....

Post by krsowles »

I'm not sure about with brakes but when I use DOT3 in my clutch line for my jeep it seems to break down and contaminate quickly. I don't have this problem with my braking systems. I just flush the clutch line once a year and am good to go. All I'm saying is; check your brake fluid and see if it looks bad. If it doesn't look exactly like it does when new, I'd replace it. Don't know why but it can break down and fail and it is cheap! Best of luck, Kelly
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Re: Braking power not what it could be on an old van.....

Post by doyoulikeithere »

is there any chance there is some leakage in the vacuum lines to the booster, or in the booster itself?
That would lessen the ability of the system to do its full potential wouldnt it?
Maybe you could reseal the threads where it strats out from the manifold, and then inspect the rubber hose where it transfers to the plastic check valve or whatever it is, and the inspect the other rubber hose that goes the rest of the way, up to the booster.

Another thing to check.....
On the rear brakes, there are adjusters that are supposed to be auto adjusting, actuated by using the parking brake.
These adjusters can get replaced with really cheep parts from china, or they can just get dirty and either way, they dont actually adjust anymore.
The result is the adjusters dont advance and all the extra travel is up to the brake cylinders to take up. Inspect the adjusters in the wheels and assure that they can travel and self adjust properly. You could have brand new rear brakes that dont work well because they dont adjust up to the right spot.

When buying parts, I noticed that a few times the brake adjusters that came in the kits I purchased were of the worst quality I have ever seen!! Spend the extra to get good adjusters at the very least.

If you just don't get as much as you would like out of the old vacuum boost system, you could look into replacing it with a newer style hydroboost system pretty easily.

Good luck.
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Re: Braking power not what it could be on an old van.....

Post by astroturf »

A thorough brake fluid flush will work wonders.
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Re: Braking power not what it could be on an old van.....

Post by 1Gary »

I have had both systems hydro in the 1994LT and vacuum booster in the 1985 shop van.Frankly I thought the vacuum system in the 1985 was better braking and that is taking into account that I did the larger brake update in the 1994LT.

Many cases of poor braking given the age of these vans in a vacuum system are related to dry rot inside the vacuum booster which leaks and you would never find it.Sure the fluid gets old and wears,but the factor that comes into play more is that booster.Replace that while checking the vacuum lines and you will be amazed at the difference.
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1985 Astro-shop van R.I.P. my friend
1994 Astro LT RWD W4.3 rod knock RIP
1982 Winnebago single rear wheel-Chevy 350 Scraped 1/28/13-broken dreams......

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