The Diesel Saga - how did it end?

You may remember that when we arrived in St Maarten we only had a single 20 litre jerrycan to power our 65 hp Mercedes diesel after a night of Heath Robinson work to give us any propulsion at all.

The final night - cabin carnage

The jerry(can) makeshift solution. Jerrycan tied to upright, takeoff and return cannibalised from elsewhere

Within half an hour of saying goodbye to Jen and Marcus (they left hand in hand with very few dry eyes in evidence), the boat was a mess. We have three diesel tanks, two under our beds in the aft cabin and one, the original one under the floor in the saloon, gravity fed from the other two. This system is one of the few areas I did not fully understand at the time so the first day was spent working out how all the copper pipes and hoses were linked together. By the end of the day I could draw this picture which shows the entire system including (in blue) our cobbled together solution. There's actually one pipe missing which I discovered later from the bottom tank to the old generator. So now I understood what the set up was. How to fix it was the next question.

I was pretty sure that at least one tank, probably the bottom one, had shaken loose the dirt, rust and dead diesel bugs of ages resulting in a blocked pipe and no fuel reaching the engine. Problem was, the bottom tank was fed from the top two tanks which I did not think were empty. Taking off the inspection hatch from the bottom tank would just result in diesel flooding the cabin as the top tanks emptied themselves. So start with the top tanks. I drained them both into jerry cans purchased from the local chandlery - in fact there wasn't a lot left. The port one was then easy as it is the cover I routinely take off to see how much diesel we have used.

Now it was empty of diesel I could get my hand into the bottom and scrape out fistfuls of brown gritty sediment. It's a nasty, dirty, slippery job and when I had finished it I still had to do the starboard upper tank. This was trickier as there were 3 copper tubes going into the inspection hatch. I cut them.
The same story - more muck.

Starboard tank- note cut pipes

Some of the debris from the upper tanks

We bought a 12v pump to swill out the bottom of the tank with diesel and then it was cloths and old T-shirts rubbed around inside the tanks for a final clean. Not perfect but not a bad job. But there was diesel everywhere. In the bilges where the food is normally kept, on the floor of the saloon, in our bedroom cabin, in the cockpit where we transferred from container to container. It was everywhere and it stank and was slippery. Friends who came aboard during the process (in fact at the end of the process) could only stand 5 minutes below before they beat a hasty retreat.

Next day it was the turn of the bottom tank. Even harder, as there is joinery including the table built immediately above the hatch. So we used a camera and the new pump to empty and review it. 180 litres in there to empty into jerry cans and put into the top tanks through a special filter. Then we saw the problem. A pile of gunge had built up from the top tanks right by the take off pipe for the engine (the long one in the picture).

It was this that was causing the problem. I knocked down the pile by feel with a coat hanger and swished it all around. Then we pumped and swished, pumped and swished but still the diesel was coming out muddy brown. It was miles better but I wasn't happy when we went to bed that night. During the night though I had a brainwave. Let's just not use the bottom tank routinely this season. We have plenty in the top tanks and can feed the engine directly from them. The bottom tank can just be spare diesel that can go through another filter before we use it if required. Then, in Grenada when we haul out for the hurricane season we can have another go at our leisure.

So that's what I did. The first pump through of the manual lift pump into the primary filter was still pretty murky but not like a chocolate sauce any longer. And it worked!! We motored much of the way from St Maarten to the BVIs where we are now and not a hiccup. "Well done John (and Gill of course, the two of us clad in little more than our underwear). Go and have a Painkiller." "Thanks, I will."