A portable oil-changer is basically a five- gallon plastic bucket with a pump mounted on top; the pump sucks up old lube oil through a changing Yacht oil 1cocktail-straw-size tube via the dipstick hole and dumps it into the pail.

I used one of these for a couple of years on my GM-powered Hatteras, and it worked fine, albeit slowly—very slowly. If you’re talking twin engines plus gears, plus a genset, pack a lunch when you change your oil, because you’re going to be there a while.

A better solution is to invest in a built-in oil-change system, comprising a reversible electric pump and a manifold of valves plumbed to your engine crankcases, trans­changing Yacht oil 2missions, and genset. You pump the used oil into a container, and then move the exhaust hose into a five-gallon pail of fresh oil (where it now becomes the supply hose), re­verse the pump, and refill. The oil is quickly pumped out and in via the oil pan drain, rather than through the dipstick tube. You’ll also have to find a place to dispose of the old oil properly—ask your marina manager or even your dockmates for their advice.

Reverse, X-Change-R, and Jabsco sell oil- change systems to suit multi-engine setups. Installation is straightforward, but drains each engine before pulling the oil-pan plug, or you’ll have an EPA-size cleanup job. I’d bite the bullet and pay the yard—its mechanics are skinnier.