Make sure your fuel tanks are clean ...

[Simi 60]

Originally Posted by thinwater

Bingo. Sometimes you have to point out the obvious.


Many sailors need to run the engine more, not less. Lengthening the season helps too.

Typical sailor probably has fresher diesel in their 20 litre tank than I do in my 7000 litre tanks.

[Mr B]

I finally got my diesel going after sitting for 7 years,
It had a couple of problems, Water was one, The lines clogged with some sort of waxy substance, The other,

A couple of gallons of water was removed from the tanks, they were almost full and I wasnt going to turf out 120 litres of diesel, $1-60 odd a litre here,

So I drained the tanks into containers, Took them home and run the diesel thru a pump and a cloth filter to remove the water and things, crap, that were in the water,
Took a couple of days to do this,
Then I replaced the racor filters with complete units from China with glass bowls, They were cheaper than just the filters here, 10,

Mine fell apart in my hands as I tried to get them apart, So I needed new ones any way,
So new clean fuel and Pump, solenoid, New filters, The tanks are now clean, Still no go,
Pulled the injectors, Spray is good like the book says it should be like,
Pulled the Glowplugs, They seem to work OK,
It does have compression, Sprayed diesel cleaner down the bores before starting, I dont have a compression tester, So dont know how much compression there is,
It dont seem to be getting fuel thru the Injector pump to the Injectors,
Or not enough to start the engine,

So I start pulling the fuel lines apart, No fuel is coming thru the lines, The lines are all clear when I pulled them out, Put them back in and still no fuel, So then I took the taps off the lines and pulled them apart, I have two directional taps for my two diesel tanks,
They both have to point the same way to make the fuel go from one tank or the other, Inlet and return from the same tank,
They were blocked solid with this solid waxy stuff, Looked like candle wax for want of a better description, Thee solenoid and fuel pump were also blocked with this waxy stuff,
Once I had that cleaned out, The fuel was now getting to the injectors, and I could bleed them, The Westerbeke I have is self Bleeding,

A good dose of start ya bastard, And finally my engine fired up and run like a swiss watch, Idled very smoothly and revved up with out a problem, No smoke either,
I couldnt run it for long as I had no water going thru the Heat exchanger, But I did have water in the motor,

I have no idea on what the waxy stuff is, Or where it came from, But it does accumulate in the fittings,

[a64pilot]

Originally Posted by Recy

What were the serious flaws in Mainsails testing?

There was no fuel in the tank.
Fuel absorbs water, an empty tank does not.


Now that is just my theory, so place as much on that as you want, I have done no testing myself.

[a64pilot]

Originally Posted by Mr B

I have no idea on what the waxy stuff is, Or where it came from, But it does accumulate in the fittings,

Most likely paraffin, it’s one of those things that can be dissolved in Diesel that can come out of suspension and cause problems, another is Asphalt, or asphaltines anyway

[deluxe68]

Originally Posted by thinwater

No, it has not. Ask any licensed tank inspector. Mainesail is a brilliant guy. There are many, topics I would not challenge him on. But I've done 35 years in the refining industry as a chemical engineer and API licensed inspector, and his testing had several serious flaws. In fact, I have replicated condensation in tanks in the lab, as well as having seen thousands of examples in the field (tank roofs are notorious for corroding due to condensation--it is so common you are actually required to inspect the roof BEFORE entering the tank.


Depending on climate, tank installation, and useage, diesel tanks can be expected to absorb 1-10 ml per season. Use enough fuel and the fuel can simply absorb this. Large water accumulation are from other sources, generally filler leaks or poor vent location or installation.

I am in the process of hunting down the vents for my tanks. From what I could see so far they do not seem to be vented from the area around the access port. I wonder if they tapped off the fill tubes.