I recently bought a 633csi, 1980 (possibly 1978.) The car has been non-op for 18 years. It has 67,000 original miles and is in mint condition. It was not running when I got it. I did a compression test and 155 all along. Unfortunately, the previous owner stripped out two plugs. I pulled the head, had it repaired and reinstalled. I also replaced all the rubber on the engine. I cleaned the fuel tank and pulled the fuel pump.

I tested the fule pump on my bench, connected + to + and - to -. The fuel pump ran but did not pump. So, what the heck, I connected + to - and what do you know it pumped great.

Reinstalled everything but no fuel to engine. Checked the pump connection and had power when engine turned. Disconnected the fuel line at the tank and poured fuel down the hose thinking that it might need to be primed. Tried it again and nothing happened. As a matter of fact, a little bit of fuel came back up the hose. Could the polarity be reversed?

Checked the relay, power at #30, 86, 87 ignition on and ground 85. What do you think?

thanks.

Brendan