Problems with diesel stored poorly?
 

When my parents stopped driving, they just parked their 1980s full-size diesel in the garage. It's been sitting for about three years, with fuel in the tank and lines, oil in the motor, etc. What would be involved in getting it on the road again? My brother says that diesel fuel that sits develops a fungus that ruins the lines, pump, injectors, etc. True?

You should post this on the Diesel Discussion, but I would recommend you drain/siphon all the old fuel out of the tank. Then use a commercially available commercial fungicide and fill with about five gallons of fresh diesel.

Of course you should check all fluids for proper level, be sure the brake pedal is firm, and fill the tires to proper air pressure. Then with a good battery crank it up.

You should do an oil/filter change ASAP, and also flush the brake system, and change the coolant using a 50/50 mix of Zerex G-05 antifreeze and distilled water.

Further driving and auditing of maintenance records should tell you what else needs to be done.

Duke

Drain the fuel tank into something clean so as to be able to check for alge. If the old fuel is loaded with "black stuff", I'd recommend that you pull the tank out and thoroughly flush it, then pour in some muriatic acid (be careful!), slosh it around then again thoroughly flush it and dry it. If you don't truly kill the alge, it will haunt you for months to come and it isn't fun. Also, add a bottle or two of algecide to 5 gallons of fresh fuel, then remove the out line from the main fuel filter, hand pump fresh fuel through until it runs clear, then pull both of the in-line filters and change them. Check the small in-line fuel filter once a week for alge.

I bought my first diesel from a LOL that probably filled the tank once every 6 months and the alge was so bad it ate through a fuel line. Good luck.

Start it up and drive it. I have parked a diesel in the yard for over 2 years and will start and run fine.

Just because a diesel sits doesn't mean fungus will grow.

Worse case is if you have fungus in the tank the car will not run long, the filters will clog and you will have to drain the tank remove the strainer and change the filters anyway, why do it for no reason. You won't damage anything.