Saving Pennies at the Pump: Fuel Maintenance, Controlling Contamination, Filter Monitoring, Questions on Additives

Presented as part of ABA’s BISC & BusMARC 2021 Virtual Safety & Maintenance Series

Early this year, The American Bus Association’s Bus Industry Safety Council (BISC) and Bus Maintenance Repair Council’s (BusMARC) 2021 Virtual Safety & Maintenance Series offered a sequence of educational webinars, covering a variety of industry-related topics.

This panel was moderated by Mike McDonal, BusMARC chair and director of regulatory compliance and industry relations at Saucon Technologies. Panel members included Robert Hitt (Prevost), David Mailhot (MCI), Dany Landry (ABC Companies), Derek Brown and Anilcan Kapucu (both of TEMSA).

The panel covered topics including fuel maintenance, fuel levels, impact of weather on fuel degradation, fuel system components, fuel additives and blended fuels, suppliers, fuel testing, filters and filtration systems, offsite fuel providers, and supplier contracts and expenses. It is presented here in an abridged format:

At what level should we keep our fuel tanks in our buses? 

David Mailhot: A little information about fuel as a substance first: Diesel fuel, regardless of its vessel, it is a hygroscopic fluid, which means that it will absorb moisture from the air around it. If you do not give it air, and depending on if you keep your tanks full, it will absorb less moisture from that air. So full fuel tanks absolutely are the best method. 

Historically, fuel was combusted in an engine an average 18 to 24 days after leaving the refinery. We have seen an increase in fuel filter and low-pressure fuel codes on a lot of our coaches due to algae blooms in the fuel itself. So, storing the fuel is important and keeping your tanks full is important, but your fuel is definitely degrading as it is sitting there in your tanks.

Robert Hitt: We have always recommended to top the fuel tanks off. A lot of that goes back to the old days when we had steel tanks in the buses. With the poly tanks, we do not see as much condensation as we used to see because the temperature changes back and forth. Even though we have not seen as much moisture in the poly tanks, we are still recommending keeping them topped off.

What are some other fuel system components we should be aware of?

Derek Brown: I would say the primary concern, especially in the winter, would be the pre-heater that is operating in diesel fuel, sort of like a fuel oil furnace in someone’s home. It combusts the diesel and it actually heats the vehicle coolant and circulates it through the vehicle. Different manufacturers have different ways of doing it, but all of those units should have a filter between the tank and the heater itself, and that is a maintenance item that you want to look at and make sure your pre-heaters are operational. You want to make sure they are up and running and you can actually bring your vehicle up to operating temperature before you even try to start the engine, which is a very nice feature for the engine and the passengers. The cabin will reach temperature much sooner than waiting on the engine to heat all the coolant.

Other than the fuel heater, what are some fuel components that we should be looking at?

Dany Landry: We talked about the fuel cap, but you also want to check your fuel VID so we are not pressurizing that fuel inside the system while it is sitting there when it does expand or contract. That way it has a way to get that air out of the system. 

Most of the problems you are going to run into is because of your air. Your air actually carries the moisture into the fuel, which tends to make that oil condensate more. So, you want to make sure you are checking your vent tube and your Espar or auxiliary heater.

When you are heating up that engine, you are also heating up your fuel at the same time because your return line for that heater usually goes through what is called a pre-charge. As it goes through that pre-charge into the nozzle, that fuel has been heated to atomize to actually burn better – but the return fuel is already warmed up and that will return back to your fuel tank where it’ll actually help heat up your fuel also. You also want to check your filters and the water in your system. 

What is the difference between a fuel additive and a blended fuel?

Mike McDonal: When I was an operator, this time of year we would go to a blended fuel and what that meant to us is either a 90/10 blend of diesel fuel and kerosene, or when we knew it was going to sustain below 10 degrees, we would go to an 80/20 blend of 80 percent diesel fuel to 20 percent kerosene.

A blended fuel is where you actually have fuel blended with another substance, versus an additive which is a chemical treatment added to 100 percent diesel fuel base.

If you are southern carrier going to New York, you may not want to load your tank up with warm fuel, so to speak. You may be better off in waiting to purchase your fuel as you get up the road a bit.

What are some fuel concerns for warmer climates?

Landry: One of the big things that you must worry about is going to be algae bloom that we see in some diesels. What happens is the water spreads in our diesel, it separates into what is called a distinct layer.

That interface between the diesel fuel and the water creates a perfect breeding ground for different bacteria and fungi to thrive in that system. Often, what we think are algae blooms are not truly algae blooms just yet, but normally a bacteria or fungi.

We tend to put in our biocides or other solutions to try to kill some of that. The problem with doing that is that some of those chemicals are hazardous to the environment. Something you can do first is trying to pull that layer off the system by filtering it out through a DAVCO kit (which is their FXP95).

Those are some of the big things you want to look for, especially in spring and summertime. A lot of that happens because we are not maintaining our tanks properly, especially our bulk tanks. They need to be cleaned and dried effectively before adding new fuel.

At what level does the bulk tank need to be maintained?

Anilcan Kapucu: I would say 20 percent to 25 percent would be essential at the beginning. That will provide an opportunity for the blending with the fresh fuels when they receive more. Instead of keeping 75 percent of the tank, you fill maybe 15 percent to 20 percent for the regular trips. Maybe 15 to 20 minutes of driving to lubricate the equipment. That much fuel would be sufficient for a while, and then they will have additional, fresh product in their bulk tank.

If a fuel additive is used, should it be introduced into the coach or through the bulk system?

Mailhot: I would go to the coach itself depending on the situation. Unless you have a fleet-wide problem that you are trying to mitigate, a lot of our customers are running different pieces of equipment that have different requirements and different needs.

And remember, you are a customer. Leverage your provider and have them test your tanks if they are willing or capable of doing that. It is good to keep that relationship alive. It adds a little back and forth.

Brown: Make sure that you maintain filters on your bulk tank. In many cases, you can prevent contamination from going into your fleet by taking good care of the fuel being delivered from the tank. Remember that those filters have been sitting there for a long time and, depending on your circumstances, may not have had anything go through them for a while.

What paperwork is needed show an OEM that warranty work was completed?

Mailhot: Basically, a customer will negotiate their internal warranty rate with our warranty department and then with that, we will pay a set amount for a repair. But again, we have a little bit of leeway. If the coach was repaired from an outside vendor and you have the invoice and all of the documentation, 99 percent of the time we will honor that. 

When filing a warranty with any OEM I think the key is to tell a story when you are filling out a claim. You do not have to be Hemingway but the more you put in to describe the failure, to describe what was done, and describe why you had to do what you did, that will go a long way and answer a lot of questions. It really helps facilitate that claim a little bit better. More information is better. 

Kapucu: Ours is not going to be different than the rest of the OEMs. Most of the items being replaced under warranty have some flat rates. We know how much it takes to replace certain things, but we also take the consideration of the status of the shop that our operator has.

For example, if a part is broken and the supplier is at fault then the manufacturer should not be paying for something that their supplier did wrong. They should obviously charge that amount from their suppliers. 

It is not only United States market but also for the whole industry – operators need to have enough information in order to claim the total amount from their supplier.

If they do not have enough data to prove that there is a fault or a failure there, then the warranty employees are not in place to approve such claims.  In order to find the real issue and to understand if this is just one-time issue or is this going to affect the whole field, they need to take precautions immediately. So, it is crucial and essential for OEMs to run their warranty procedures properly.