mayberg

Friends,

My air pump siezed up - the pulley won't turn and the belt just squeals. For the time being I pulled the belt (drives AIR pump and compressor) and I still intend to drive the car.

There's nothing in my shop manual that suggests the check valves won't do their job. I plan on checking them shortly to make sure air flows one way.

Any trouble with leaving the AIR pump disconnected for the time being (including road trips) with the hoses connected to the manifold?

mayberg

OK - check valves check. I can't draw air. But the diverter valve doesn't hold vacuum - is it supposed to?

JohnZ

99.99% of those old diverter valve diaphragms fail and leak, which does two things; 1) It creates a manifold vacuum leak due to the ruptured diaphragm, and 2) The valve fails open, which dumps air from the pump into the manifolds all the time, which causes "popping" on over-run (assuming the pump is operating, which yours isn't). The diverter valves were discontinued by GM many years ago.

Plug the hose to the diaphragm so you won't have a vacuum leak.

Not running the pump won't hurt anything; I "gutted" the pump on my '69 Z/28, knowing it would seize eventually if I didn't (removed the vanes and springs) so it's just an idler pulley now, and you can't tell the difference by looking at it. Also removed the stainless insert tubes from the manifolds, put a #10x 1/2" flat head machine screw in each hole, then re-installed the air manifolds; the tube nuts seat just as they did with the insert tubes, but the holes are plugged so hot exhaust gases don't even get into the tubes, much less to the check valves. :thumbs: