bad master cylinder, or the vacuum booster?

bad master cylinder, or the vacuum booster?

Postby earlman [OP] » August 30th 2012, 2:34am

Hi guys!

1997 Safari Perversion Van.

The other day I just tapped the brakes real quick, and the pedal suddenly got spongy. Not all the way to the floor, but the travel is greater now, and the stopping has been reduced. It still stops with a little more pedal travel, and the dummy light came on (BRAKE).

No puddles under the van.
Master cylinder is full.
The pads are newer, and should be fine.

So... do you think it's a bad master cylinder, or the vacuum booster?
Thanks again... and again... and again...
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Re: bad master cylinder, or the vacuum booster?

Postby chevymaher » August 30th 2012, 2:37am

Master cylinder.
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Re: bad master cylinder, or the vacuum booster?

Postby earlman [OP] » August 30th 2012, 2:39am

I just found this on another thread.
Maybe I should read these things once in a while! :D

Re: Test my Vacuum Brake Booster?

by Shad0wXCalibur » January 2nd 2012, 3:16pm

If there's no air in the system, then it sounds like a worn master cylinder. A bad vacuum booster would give you a stiff pedal like you get when the engine isn't running.
Original Poster [OP]
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Re: bad master cylinder, or the vacuum booster?

Postby RECox286 » August 30th 2012, 2:42am

Bingo !

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Start a fire for a man and he will be warm for a day.
Set a man on fire and he will be warm the rest of his life.

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Re: bad master cylinder, or the vacuum booster?

Postby earlman [OP] » August 30th 2012, 3:00pm

I like this site. All of you good people help to make owning these vans easy!
Thanks very much for taking the time!
Beer...beer...beer!
:ty:
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Re: bad master cylinder, or the vacuum booster?

Postby Lumpy » August 30th 2012, 3:42pm

earlman wrote:
...Beer...beer...beer!
:ty:



Beer? It's 7:41 in the morning. Have some decency for heaven's sake. Wait another 4 minutes.


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Re: bad master cylinder, or the vacuum booster?

Postby RECox286 » August 30th 2012, 3:51pm

Itisalwaysafterfiveo'clocksomewhere...

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Re: bad master cylinder, or the vacuum booster?

Postby earlman [OP] » September 20th 2012, 2:14pm

It's always "beer o'clock" here in Milwaukee.

Get the new master, put it in, find out that there is no change! WTH???

BUT, now with the new master, I find out that the original problem was that sneaky broken brake line that sits above the gas tank! Here in Wisconsin (snow and ice), that is a monumentally stupid place to put the line. Read about it, here: viewtopic.php?f=45&t=9731

Get new line, put it in (from the abs back), all is good.

--->>>But think, now. If the line was bad BEFORE the new MC was in, why wasn't the resivoir empty? There must have been something wrong with the old MC. Maybe the old MC was bad the whole time anyway, and only stopping with two wheels (instead of four). THEN, when the new MC went in, THAT'S when the line blew? (I've seen new MC's blow old lines ALL the time) <----

Well, ours is not to question why, but now the thing stops so good it da** near shoots me out the front window!

Case closed. Thanks again, all!
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