Can I still use old diesel fuel?

[StuartSailor]

Good Day All,

This question is less about cost than about quality of the diesel. I have about 1/2 gallon of diesel that I've kept on my boat to use when replacing my primary Racor filter. I believe this fuel to be 2-3 years old. I had every intention of taking it to my mechanic to dump but when I poured it in a Gatorade bottle it looked great, with nothing floating around or settled on the bottom.

So, would you use this old diesel? Thanks.

Jesse

[Kenomac]

Yes you can use it. Unlike gasoline, diesel is just fine to use after many years, just so long as it's clean. I wouldn't hesitate to put it in my tank.

[JPA Cate]

Yes, as long as it is uncontaminated.

A.

[tkeithlu]

I'm tempted to ask if you have an old diesel as well. Old Detroit Diesels like my 4-53 are reputed to run on buttermilk, and plenty of people put their used engine oil in the tank.

[a64pilot]

A half gallon?


Sent from my iPad Pro using Cruisers Sailing Forum

[savoir]

Contaminated diesel will be cloudy and clean diesel clear, but for the tinting.

[StuartSailor]

Thanks for the responses. I will definitely return the diesel to the can.

[RaymondR]

Rudolf ran his on peanut oil.


Unlike spark ignition engines which are pretty particular about the fuel, mainly because it needs to go through a carburettor and become a vapour, compression ignition engines will run on just about anything which flows and will support combustion. Not so common these days but the bunker fuel they ran ships engines on was often so thick and gludgy that steam coils in the fuel tanks were required to get the stuff to flow. Some light crude oils straight out of the wells can be used to run diesels after centrifuging out the water and solids. The stuff is millions of years old when it comes out of the ground anyway, a few more months is probably not going to make much difference to it.

[capngeo]

I think the fuel in my boat's tank is two years old!

[SV Bacchus]

Originally Posted by a64pilot

A half gallon?

+1 I had the same thought

[S/V Alchemy]

The fuel in my tanks is seven years old. I filled my keel tanks full in late 2008 and then replaced everything the fuel led to. When I was ready to launch in 2014 with the new motor, etc. I pulled the pickup tubes, cleaned out the very little amount of muck, and then ran the tank through the Racor polisher. It's fine.

[PappysSailing]

One of the mechanics that walks our docks said that after changing the primary fuel filter on a old boat, he started its diesel engine using the fuel in the tank that had been sitting there for at least eight years... No problem since the owner had kept up a proper schedule w additives, algaecides, etc. Cheers, Pappy

[svthreecheers]

For old Diesel fuel make sure you use a good Stabiliser and Lubricity Additive.

[Scout 30]

Actually old diesel has more lubricity than new diesel which is ultra low sulphur.

[Steve Bean]

Here's a slightly off-topic bit of information. Sulfur does not provide lubricity, but the process of removing sulfur degrades the lubricity.