Master,
In my feeble attempt at replacing the vacuum line to my power brake on my 1989 Trooper 2.6L 5 Speed, I discovered a "check valve" in the hose. The Cro-Magnons at the Auto Parts place were mystified, leaving me with no convenient replacement. What is the function of this valve, and is it essential?

Somewhere between essential and nice-to-have -- I recommend it. Without it, your power-assisted brakes go away immediately if the engine dies.... with a functioning check valve in place, you'll get a couple good shots of assisted braking before the pedal gets unhappy. The valve itself hardly ever faills - I recommend recycling your existing valve by splicing it into the new hose. You can test your valve by sucking/blowing on each end. The vacuum booster side should blow freely, but not permit you to suck, and the engine side should suck and blow freely. There's an easy joke in there about how hard I suck. <img src="/forums/images/graemlins/pfft.gif" alt="" />

If you do not have that valve, you should be able to snag one from any u-pull-it junkyard.

Randii

Master,
I am trying to get rid of any 16 year old hose. Is there someone who can sell me a new hose?

I bet Isuzu has a hose for you.

Call St. Charles. www.stcharlesauto.com and ask for Merlin.

Michael

Send Jerry Lemond a note a jlemond@bellsouth.net

He's got the hoses in stock and will probably sell it to you
cheaper than anyone else. The hoses he has are factory hoses.

This should be a 1/2 inch neoprene vac hose, and the booster check valve is standard Chevy (or GM) and rarely fails. Lots O' GM influance on those great old Zus.
Rare for that hose to fail (but possible), check for tight valve adjustment.

It's a 16 year old hose, and showing cracks around the ends. The checkvalves still holds, but it's time to refresh.. Thanks for the GM tip