One of the most expensive repairs any diesel engine owner can make is fixing engine problems caused by bad RV diesel fuel. The good news is you can avoid a trip to the mechanic by paying attention to engine performance, how you drive your RV and what you put into the RV’s tank.
Bad RV diesel fuel can start here.
The Signs of Bad RV Diesel Fuel
Bad RV diesel fuel symptoms aren’t too hard to recognize. You’re looking at trip to the mechanic if your diesel RV engine:
- Won’t start
- Only starts after a long, hard crank
- Runs rough
- Feels like it’s running on low power
- Has knocking sounds
- Blows blue exhaust smoke
- Has poor fuel economy
Sometimes low quality diesel fuel is the crux of these issues, but more often they can be traced to deposits that get into your engine. When the deposits mix with diesel fuel and flow into the fuel lines, filter and injectors, you’re looking at an expensive repair bill.
If your engine is running fine for now, these dos and don’ts can help keep it that way:
Tips to Avoid Bad RV Diesel Fuel
1. DON’T buy the cheapest fuel.
Buying on price alone isn’t always the best idea. Reliable, name-brand service stations have more resources to treat fuel with the care it needs. Always fill your tank from any well-known reputable filling station, not the no-name bargain ones.
2. DO avoid lonely, remote gas stations as much as possible.
Traveling back roads is fun but fuel up in the big city before you head out. Rural gas stations in agricultural areas have lower fuel turnover which means diesel has been sitting in their underground tanks longer than it should. The longer diesel sits in any tank, the greater the chance that algae and other sediments have accumulated in the bottom.
3. DON’T fill up at stations getting a fuel shipment.
Any time new fuel is added to the underground storage tanks at gas stations, sediments get kicked up into the tanks and can potentially contaminate fuel. If you see a fuel truck servicing a gas station, skip that one and find another.
4. DO replace your fuel filter at regular intervals.
Fuel filters do just what they say: screen out impurities in fuel. To avoid bad RV diesel fuel, follow your RV engine manual and replace the fuel filter when recommended, more often if you’re RVing at Burning Man or other places with extreme environments. Only use fuel filters made for your truck: aftermarket ones may not do the job.
5. DON’T drive with a low tank.
If you only fill up when the low fuel light goes on, break that habit now. By driving until your tank is nearly empty you run the risk of putting older, stagnant fuel from the bottom of your tank into your engine. Never let your tank get below the ¼ mark.
6. DO fill up before you store your RV.
Any air that’s sitting inside the tank will have the same temperature and humidity of where you last traveled. At night when the temperature drops, that air and humidity will condense, fall to the bottom of your existing diesel fuel and give an open invitation for algae to bloom. You may also want to add a biocide (available at marine supply stores or online) to kill any new algae blooms inside your tank.
Some RV repairs are unavoidable but you can minimize the damage to your wallet and stay on the road longer by being proactive about keeping your diesel engine happy.