[tubman]

I had a '51 Mercury engine in storage for at least 20 years. When I finally pulled it out and fired it, it took at least 30 seconds for it to build any oil pressure (this was in 10 second increments with a lot of checking in between). It seemed like an eternity, but on the third or fourth start-up, it finally came up and ran at 55 psi. I think that if they are stored that long, the lose their prime. In retrospect, if I had to do it again, I'd pull the pan and pack the pump like a fresh build.

It's been on the road for about 3 years now with no ill effects.