Air Pump

Andrew Sandiforth wrote:

My air pump came to a screeching (literally) halt today. Froze up solid. I removed it tonight and took it apart, but I'm not sure I can fix it. Amazingly simple device. Has two scraper like impeller blades mounted on a concentric center wheel that extends and then contracts them as the rotate...

I had an air pump freeze up on me too. It was a Brit car but not the Jag. It took a bit to get it all apart and the pulley pressed off, but I didn't need any special tools. What I found was a bad bearing in the rear housing. I found the tiny $12 bearing at a NAPA auto parts store, as there was a part number on it, installed it and carefully reassembled the unit. It works fine now.

The blades look like a carbon type material. They are pressed against the inside chamber by springs located in the center hub under the impellors. I'm not a big fan of extra devices on the engine, but a bit of fresh air to help burn the unburned fuel when the engine's cold, is probably a good thing for the catalytic convertor.

While I've not actually checked, I understand these pumps are pretty common and a new or reconditioned one can be bought at good parts stores for under $100. (YMMV)

I have posted this warning before, and I will again: don't waste your time maintaining your Jag's air pump system unless you ALSO remove the air tubes from the head and clean them out. Every one I have ever seen has been plugged with carbon deposits. It would take a really motivated air pump to blow air past clogged tubes.