MY EXPERIENCE WITH DIRTY FUEL
Submitted by Tim Davis
“Gale Force II”

Last June while entertaining guests on “Gale Force II”, a 1987 Hunter 40, I experienced the dreaded “dirty fuel” syndrome. We had a pleasant run up the lake to Lake City with stiff winds on the starboard quarter when we decided to come up wind and drop sails to go in to Lake City. The engine started but faltered after about 3-4 minutes. Attempts to restart were futile so we dropped anchor just outside the Lake City Marina. After conferring with Dan Fedie we decided to sail as close to Dan’s Marina as possible and then be towed. Some of you were entertained as we were not only towed in by Dan, but also had a “brake boat” on the stern to prevent us from being pushed by the tail wind and careening into other boats. It wasn’t our best hour, but a lot better that coming into the marina with your boat on fire. But that is another story.

I knew it was dirty fuel. The boat had been shipped from St. Louis the previous September, and according to the harbormaster the prior owner had moved it from Lake Michigan in 1999 and treated it as a floating weekend cabin for the next six years. Old fuel had been allowed to sit in the tank and gather a nasty layer of particulate and dead microorganisms. The rock and roll trip to Lake City had stirred it up just enough to clog the fuel filters and halt the engine. I should have known better! Diesel engines ask for clean fuel and clean air. If they get what they want they will provide their owners with faithful service.

I attacked the problem by pumping the old fuel out of the tank. Fifteen gallons of disgusting grunge! No wonder the Iron Genny quit on me! I was able to swab out the near half of the tank, rinse it and replenish it with several gallons of fresh fuel. I went one step further and replaced the old stage one water filter with a new Racor filter, as well as the secondary filter on the engine block. I learned how to bleed the air out of the system, one of those things I had always meant to add to my list of talents but never got around to learning. Necessity forced me to acquire that skill right now. The Yanmar started and ran well under power in the marina. I pronounced the problem cured and made plans for the next sailing trip. To my credit I did one more thing to prepare for the possibility that “it could happen again”. I laid in a supply of extra filters.

The next outing was destined to be a repeat of the former. Same wind, same direction with another good run up the lake to Lake City. This time the wind was so strong and considering the inexperience of our guests on board, we decided to turn around and do some motoring on the way back to Pepin. Again the Yanmar coughed, sputtered and died. What?! Not again! This can’t really be happening again! Restarting attempts did produce a running engine but not more that 1200 rpms and anemic performance under load. But hey, I’m a Boy Scout – I’m prepared – I have my extra filters on board! So I drop anchor and after getting the guests settled I go to work down below in a pitching and rolling boat. Have you ever worked on a boat in rough seas with the smell of raw diesel fuel and bilge odors fresh in your nostrils? It’s enough to turn the strongest stomach to mush! I replaced the Racor filter and the secondary filter, bled the air out of the system and hit the start button. The Yanmar roared to life. Alright!!! Life is good!! My ingenuity and newly acquired skills paid off!

Unfortunately that was not the case. The engine did not perform any better than before. With my anxious crew (read spouse) I radioed the marina for advice. Our friends the Bloom’s volunteered to tow us. So we had to suffer the humiliation of a marina tow for the second time in two weeks. At least this time the slow running engine allowed us to come in under our own power.

Now I am really determined to go after the “dirty fuel” problem. I realize that my attempt at swabbing out the tank was only half hearted, because I could not get past the baffle plate that separated the tank into two parts. There was a layer of crud still in the tank on the other side of the baffle that was polluting the fresh fuel. Rod, the diesel mechanic, suggested that I cut the tank moorings and remove the tank to properly clean it. That looked like a nightmare to me. The other solution was to install access panels in the top of the tank that would allow my hand and arm to get into both sides to thoroughly clean every square inch. This I did. I found on line at www.seabuilt.com access panels made just for the purpose. Great idea! I would forever be able to clean out old fuel by opening the access panels and would never be caught with a starved engine again. I won’t go into the pure misery I went through installing the access panels in extremely tight quarters. Just know that the job got done.

Well, perseverance paid off this time. The Yanmar finally got what it wanted and we have had no dirty fuel problems since.

Later when I told Rod about my experience he stated that it is very likely that at least a third of the boats in Dan’s Marina had “dirty fuel”, and that problems similar to mine were “just a matter of time.” Sure enough, about two weeks later “Connamera” had the same problem. Save yourself the trouble we had and every three years be sure to empty the tank completely, get inside it and make sure the slime layers have been removed, and finally replace all fuel filters. Happy and Trouble Free Sailing!

this site maintained by beth anderson of plum creek associates