Feb 15

Of black sludge and liquid gold

Tag: boat workjonny5waldman @ 2:15 am

    Matt was driving north over the Bay Bridge. I was gazing out the passenger window, feeling pensive. This was two weeks ago. We’d spent the afternoon buying parts, and were eager to get back to the boat. Four tankers sat at anchor in the bay far below, in line with the current. I said it was neat how even in this modern world, boats and planes must understand and obey tides and currents and winds, etc — and how crazy it was that only cars don’t really have to make way for nature, unless it snows, or gets really windy, as it is prone to do on sections of I-80 in Wyoming. I asked Matt if he’d ever buy a diesel car, and he said that next time he’d like to, if they made a diesel something-or-other like an X-terra. He said it’d be cool to be able to work on it, and I didn’t dissuade him of the notion.


    We got to talking about the differences between diesel and unleaded engines — how the power from an unleaded engine is like the power required to ride a bike with sneakers, pounding only on the downstrokes,  while the power from a diesel engine is like the power required to ride a bike with clipless pedals, a nice smooth round even stroke. We were pretty proud of that metaphor. We talked about how an unleaded engine can propel a car from 0 to 60 in 5 seconds, while a diesel engine can eventually propel a car to 60 while pulling 100,000 pounds; and how unleaded fuel in a diesel engine destroys it by exploding way too early in the cylinder, pushing the piston down too soon; and how diesel fuel in an unleaded engine just won’t explode no matter how big a spark you throw at it. We were grappling with the big picture, so that the little details of our engine would make more sense when we tinkered with it later. Thinking about it all, I marveled at how not-understood the distinction between diesel and unleaded engines probably is — akin, perhaps, to asking Americans to name the 3rd president or the capital of Nigeria.


    It was nearly sundown by the time we began installing the oil transfer pump. Matt in particular had been excited about the project for months, ever since he first changed the oil in the engine. That task — changing the oil — had been a bear. A total bitch. Because the drain plug was nearly inaccessible, and, at any rate, a drain pan wouldn’t fit under the engine, changing the oil the standard way wasn’t possible. Instead, it required pumping out the old oil via a long, narrow hose snaked in through the dip-stick tube, and then pumping in the new. It was such a laborious, lengthy, messy – -and apparently ineffective — solution that none of us wanted to change the oil, which is not a good thing. Hence the transfer pump. We planned to remove the drain plug, attach a valve, and connect a hose from it to the pump — so that from then on, changing the oil would require only the flip of a switch and the push of a button. it would be glorious.


    But first: how do I know the pumping-through-a-hose-snaked-in-through-the-dipstick-tube method was ineffective? Two ways. First: Our engine takes 4 quarts of oil; it says so in the engine manual. So an oil change should entail removing 4 quarts of nasty black oil, and putting 4 quarts of clean oil back in. But notes in the engine logbook, kept by the meticulous previous owners, reveal oil changes of less than 4 quarts. Since 1993, the numbers look like this: 3.75 qts, 3.5 qts, 3.5 qts, 3.75 qts, 3 qts, 3 qts, 3 qts. Given how inordinately difficult it is to manually pump the oil out of the dipstick tube a little bit at a time, these numbers aren’t so surprising. But what’s the point of changing the oil if you’re not going to change all of it? It’s like only flushing the toilet partway. Second: having changed the oil on cars, I am familiar with nasty, black used oil. The nasty, black, used oil in the bottom of our engine was something else. It was sludge. Big surprise, considering how hard it was to pump the gook out through a tiny hose.


    So: we screwed five bronze fittings (a 90-degree bend, a connector, a valve, another connector, and a hose fitting) together, put some bomber glue (3M’s 5200) on the threads just to be extra safe, and connected them to the spot where the drain plug had been. For what it’s worth, this was beneath the most inaccessible underside part of the engine, and required creative squirming just to get your arm in there, let alone use a wrench. After that, we mounted the pump on the bulkhead just above the engine, and connected the hoses. Then Matt wired it up. Finally, around midnight, we changed the oil by flipping a switch.


    The pump hummed, and the oil level in the 4-quart container began to fall. No mess was made. Nasty, sludge-like oil did not leak anywhere, or stain any clothes. The operation took only about five minutes. When the 4-qt oil jug was empty, we turned off the pump, closed the valve, and checked the oil level with the dipstick, just to make sure everything was OK. At first, the oil level seemed low, so we wiped the dipstick clean, put it back in, pulled it back out, and inspected it again. Matt grew serious. "Oh shit," he said,  "it looks like there’s water in the oil." I corrected him:  the new oil was so clean and transparent, and we were so accustomed to looking at black, oily sludge, that the new oil, thin and golden, looked watery. But it wasn’t. And we had the perfect amount, right between the MIN and MAX lines.


    I expect that our engine will be very happy with its new treatment.

2 Responses to “Of black sludge and liquid gold”

  1. John says:

    Hey guys – great website – you all remind me of me 20 years ago. Now dumb question – I am like Jon 🙂 did you pump the old oil out with the transfer pump before you put the new oil in? 🙂

  2. Janine says:

    Very nice website and Article! Thanks!

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