Vaccum pump resolved

I was having trouble connecting up the vacuum pump for the power brakes.
Actually, it worked fine - it was just working too often - constantly cycling on and off, which indicates that there is a vacuum leak somewhere. The pump is mounted under the passenger side of the top rack beside the motor, so I have to pull out a couple batteries out of the rack to get to it. Most people connect the pump to a vacuum reservoir (essentially a tin can with a check valve and a hose fitting) which stores a little more vacuum than the booster alone. I've used one of these on a gas car a while back and am skeptical that they make any real difference, so decided to skip this piece and connect the pump to the vacuum switch and to the booster. I had a T fitting to hook this up and, it looked good, but, as I mentioned, didn't work real good.

One great help when dealing with this is having the right tools. I don't. But AutoZone does. They are a car parts retailer in the US and they have a great tool loaner program. Last week I drove to one of their stores and, after leaving a deposit, walked off with a hand held vacuum pump complete with a gauge.

I quickly found out the pump leaks! When it shut off the vacuum drops to zero. I got a check valve from Kragen (sorry AutoZone, but Kragen is in walking distance...) and after plumbing it in, it made no difference. After a few checks it was clear that the check valve didn't stop the leak. A little more testing and it was clear that the check valve was defective.


Later, while working on wiring up the charger, I had an epiphany. I didn't need another check valve, I just needed to move the stock one to the other side of the vacuum switch. The stock check valve is inside the hose that comes off the booster. So I pulled it off and replaced it with a regular hose. The check valve hose got moved to between the T fitting and the pump and voila. Works fine.