Saturday, March 13, 2010


Loyal readers (both of you) may remember that when I first started the car up, I reported some odd behavior from the vacuum pump. It wouldn't come on regularly and the brake pedal had an odd feel to it. At the time, the car was still up on the jack stands, so I couldn't tell if the brakes actually worked or not.

A few days ago, my father was driving the car and I noticed that the vacuum pump came on and was staying on for what seemed like a very long time. I asked him to pump the brakes, and within 15 seconds or so, the pump shut off.

Well today, I headed out of the garage with the aim of giving my wife Mary the opportunity to drive the car for the first time. As I pulled out, I noticed the vacuum pump running non stop like it had when my dad drove it. I pumped the brakes but found that they were getting no vacuum assist at all, and the pump still wouldn't turn off, so we had to scratch this outing.

I pulled the car back in the garage and started looking, tinkering and thinking. In short order, I realized what was causing this repeated problem, and with a few simple tests proved my hunch correct. The vacuum canister came with a check valve, and that check valve was sticking open. What that meant is the pump couldn't draw down a vacuum (which is why it ran non stop), consequently the brakes had no assist.

I've ordered a replacement valve and some other fittings to make the whole assembly from the vacuum canister to the brake assist drum a little cleaner. Until they arrive, no EV driving. :-(


Gam0ra said...

That's what the handbrake is for! It's totally safe, I drove my Renault R3 for over a month with only the emergency mechanical at the bottom of the break pedal travel and the handbrake.

Of course...I also drove a '67 Mustang with a broken A-Frame for about 6 years...and I did NOT drive slow.

Come to think of it...maybe you shouldn't listen to me.

Tim Catellier said...

Point taken!