Samples are fine, if the shipowner will pay to have them tested. I bunkered HFO 440 Cts in Newcastle, NSW, from road tanker trucks and the project engineer (the company had just bought the ship, which had been laid up) told me he had a great deal on the fuel, I was not to take samples, testing was too expensive.
(I found out a few years later that they don't stock HFO 440 Cts in Oz, so god knows what kind of deal was involved and what king of garbage we got. Did notice a lot of metal fines in the purifier sludge though, so it probably had a high content of used motor oil)
I only work here as boat people and, as we all know, the lowliest office cleaner is more senior to the most experienced seafarer, in the eyes of office people. You don't argue with Project Engineers based in the Office if you want to hang on to your job.
So I didn't take samples and we headed off to Tahiti for our next bunkers.........via the Tasman Sea......in June. Buddy had insisted that the drums of paint he had got a great deal on should be stowed on the boat deck and we should be ballasted down. The Mate and Captain tried to explain what a stiff ship was, but he insisted. so we sailed, GM of 6 metres, 6 second roll. By the time we passed NZ's north island, it was force 8 on the beam, rolling 25 a side and we were cleaning the HO purifier every watch. (only had one) By the time we were 1000 miles from any land, between NZ and Tahiti, it was blowing force 9, still a 6 second roll, 30+ a side, purifiers were being cleaned twice a watch, pulling out biological spaghetti, and we had 2 hours of useable, purified fuel left in the day tank.
I was a little concerned that we'd have to change over to MDO to make Tahiti, but then we started to purify more fuel than we burned. We continued cleaning purifiers twice a watch until we reached Tahiti, doing that 6 second roll all the way. (Thank God for Roger and Brent!) I ordered and dumped 2 drums of biocide in the HO storage tank (there was only one, settling and day tanks were empty) before I bunkered, and we had no more problems. We carried that purifier sludge in a fwd ballast tank until we reached Halifax, where we could get it pumped out to sucker trucks at pier 21, 40 tonnes of it! The charge for accepting the sludge was $1 a litre, $40,000 total! So is testing expensive?
It should be pointed out that the engine, a Sulzer 5RND58, had only ever burned MDO, never seen IFO 120, let alone HFO 440, so she wasn't equipped for heavy oil. The company which bought the ship had only ever operated workboats, small stuff, nothing bigger than AHST, all medium speed trunk engines burning MDO. Seemed I was the only guy around who had ever worked a large slow speed with heavy oil.
Moral of the story? TAKE SAMPLES AND HAVE THEM ANALYZED BEFORE YOU SAIL!
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