Let’s talk Fuel Filters

[ChasingOurTrunks]

Hi folks

I know the majority of us never leave North America and as such fuel filtration may not be high on the priority list, but it’s a worthy discussion all the same. In remote areas fuel is often dispensed from questionable containers with a high risk of both particle contaminants and water contamination. Even in major cities, sometimes a service stations holding tanks are running low and you fill up with the silt and dregs from the tank bottom. Sometimes this is bad enough to stop an engine, other times it’s a cumulative effect over a long time.

What are people running for filters for gas engines? Brands and models? Have you done water and particulate filtration separately or all in one? Do gassers designed for modern ethanol blend fuels even need water separators? Do newer rigs struggle with the added resistance of a filter in the lines with modern day, high pressure injection systems?

I don’t have any experience with diesel filters on 4x4s, but chime in if you have experience with that too.

 

[Explorerinil]

On diesel vehicles you want to get fuel from areas that sell allot of volume. You also want to read the micron rating requirement and run filters that meet or exceeds those factory ratings. I run fleetgaurd nanonet fuel filters and change them every 10k. In the winter I run optilube winter formula to prevent gelling.

On any gas powered vehicle I’ve owned, I run factory fuel filters and change them at the required factory interval... never had a problem.

 

[Inyo_man]

Driving through the jungles of Central America ('81 Toyota 4x4 pickup 22R/Weber carb.) I brought box of fuel filters and changed them as needed- if I recall correctly, they were Fram filters. I had installed an in-line filter mounted on the inside front wheel-well in the engine bay, so swapping them out when no hassle. Additionally, when filling from 50-gallon drums, or questionable sources, I always ran the fuel through a pre-filter. At the time I was using a filter made for filtering boat and surfboard resin. Worked a treat.

 

[Explorerinil]

Driving through the jungles of Central America ('81 Toyota 4x4 pickup 22R/Weber carb.) I brought box of fuel filters and changed them as needed- if I recall correctly, they were Fram filters. I had installed an in-line filter mounted on the inside front wheel-well in the engine bay, so swapping them out when no hassle. Additionally, when filling from 50-gallon drums, or questionable sources, I always ran the fuel through a pre-filter. At the time I was using a filter made for filtering boat and surfboard resin. Worked a treat.

That’s some good advice for anyone traveling to areas with questionable fuel sources.

 

[chet6.7]

If I was really worried I would use a a frame/body mount like the Jegs,Racor is a good brand. The smaller inline filters were easier to change than the one in the carb on an old truck. Does your vehicle have a stock filter?
Are you thinking about an inline filter like this?

Fram G3 Fram Fuel Filters | Summit Racing

Free Shipping - Fram Fuel Filters with qualifying orders of $109. Shop Fuel Filters at Summit Racing.

www.summitracing.com

Or, something like this?

Inline Fuel Filters - Performance Fuel Filter - JEGS High Performance

Purchase effective inline fuel filters from JEGS High Performance. Our high-performance fuel filter products will keep your carburetor or fuel injection system running clean. Shop our collection of inline fuel filters online now!

www.jegs.com

 

[lugueto]

Stock fuel filters work better than you think, at least on gas engines. We've rarely had problems with fuel, none that can't be solved quickly at least. Diesels here aren't common, but the only modification to the filtering system I've seen have been adding Racor water separation systems.

We have bad fuel contamination issues in our country, with gas stations out of regulation and in bad shape, fuel shortages and shady fuel storage in remote places it can get scary quickly, specially when you're not used to it. We use water filtering funnels and adapted fuel filters into syphon hoses as to avoid big particles from getting through. But you don't use these in gas stations, and that's where you usually get into trouble down here. We change fuel filters relatively regularly, maybe every 10.000 miles and don't let the fuel go below 1/4 tank if we can help it to avoid the pump from picking up most of whatever grime is left on the bottom.

The two times we've run into issues have been these:

Once we were filling up in a small city in the middle of the country and just when the pump stopped, another car pulled up to the gas station and told us to shut it off imediately because fuel was contaminated. Too late, I had just filled 40 gallons or so. The other vehicle travelling with me about the same amount. Every single car that filled on that pump that day was left stranded. It turns out, the fuel truck had made a huge mistake and dumped diesel into the gasoline tanks, and we were fed the gas/diesel mix. The vehicles wouldn't start, obviously, so we had to drain our tanks back into the stations main tanks (major safety and environmental hazard), purge the fuel lines, change fuel filters and fill from another pump just to get back on the road. Took us about an hour and a half, no harm done thankfully.

The only other time I had an issue was worse, I was travelling alone for the day, had to make about a 600 mile round trip that day and had done about half way when the car started sputtering. It started getting worse and worse. Since it was going to get dark soon, and I had no CEL on and had no sign of overheating or anything of the sort I pushed on. By the time I got home, I could barely do 40mph and was sputtering badly, it was dark and thankfully I didn't break down. I got home with only 2 out of 4 cylinders firing. The truck was fed badly contaminated fuel, fuel filters were badly clogged (both aux tank, main tank and the engine's filter), fuel lines had to be cleaned, injectors and what not. It sucked. I though I had pictures of the dirt inside the tanks but I can't seem to find them.

In any case, third world problems. If you're in the states and have common sense, you'd never run into these issues. If you're travelling in countries where this is an issue, bring extra fuel filters, don't fill up on gas stations that look way too old or sketchy and don't fill up from containers that look too dirty. If you absolutely have to, filtering funnels work great.

 

[javajoe79]

My NPR currently just has a stock filter/separator from a HINO truck. I have yet to wire it in but it has a heater and water sensor built in to it. If I end up going anywhere that might have iffy fuel, I'll upgrade my system. A more robust separator and more filtration probably. In motorsports applications you can buy all sorts of nice filters that are easily serviced. Washable stainless screen filters are nice for prefilters before the pump then something with a smaller micron rating after the pump. Probably a good idea to have a tank drain too so you can occasionally drain it when it's almost empty so you can wash out any accumulating sediment.

 

[Regcabguy]

The 50's and 60's Baja explorers would use a chamois at the filter neck to filter out crude.

 

[Hillbilly Heaven]

Oh gas engines I like a final filter that strips and captures in water that maybe in the gasoline. With ethanol being used more and more these days, the prominence of water is greater. Most modern (2000+) fuel systems will not be harmed by water as they are either stainless or some form of plastic. Fuel injectors are where damage occurs. Beside internal combustion engines do not run well on water.

I like to stop the water before reaching the engine compartment. A spin on type filter will do more at stopping water than an inline cartridge type filter. It offers the convenience of being removed to drain the water in questionable fuel areas. The filter does not have to be replaced just drained.

I have found this particular filter as one of the best. Size maybe a problem for some tying to find a suitable mounting spot. Plumbing may take some creativeness.
This size will work for most common usage. https://www.fstperformance.com/rpm300 4 Micron rating with 183 square inches of surface area.
Image of how the filter strips and captures water. The secret is in how they strip the water as most spin on filters have a empty cavity at the end of the filter.
https://www.fstperformance.com/flomax-repl-filters

These guys actually manufacture these same filters for Mercury Marine OEM use

 

[grizzlyj]

Mr Funnel?

 

[Hillbilly Heaven]

Mr Funnel?

Kind of gimmicky. No published specs and will only separate water from fuel if fuel has time to rest before pouring. Only lower 1/3 of filter blocks water. It is a water blocking type filter not a stripping type. There is a difference. A water blocking filter will actually stop all flow if too much water. Curious as to the micron rating of the filter since no published specs. Typical online marketing hype no real world long term usage.

 

[ChasingOurTrunks]

Thanks for the ideas and links, everyone. It seems to me that there are a few good 'systems' to have in place, but I'm hesitant to use anything external like funnels or pre-filters.

In North America/Europe/Australia, it seems that the risk of fuel contamination is so low that it's likely a person like me wouldn't have the discipline to use an external solution (i.e. a funnel) with regularity, and that may come with it's own issues of storing a gas-smelling funnel somewhere on or around the rig. An integrated solution is probably ideal.

As far as OEM filters goes, from what I can tell reading online (more research to do to be sure) our vehicle the filter is integrated with the pump, so apparently you have to replace both at the same time. It's a $170 part. A secondary filtration would be useful before stuff gets to the tank, but barring that, another one before it gets to the motor seems like a good idea.

Does anyone have photos of their installs?

 

[rayra]

With many vehicles now having pump and filter inside the tank, you need to keep the crud out of the tank in the first place. Best thing for that would be a funnel or clear PCV hose with some sort of inline filtration ability. Keep the junk out of your tank in the first place. And if the facilities are that crude, maybe even take the time to use a bucket as a settling device. Painter's paper / mesh filters or even coffee maker filters, if nothing else.
Alternately you wrap that or something like it right on the nozzle of the fuel station pump. A woman's knee-high nylon stocking or equivalent would also work well for that.
There's no useful purpose to putting another filter downstream of your factory filter.
Decades ago the go-to was an inline filter with a fine mesh element and a glass cylinder. You could unscrew the two ends of the filter body and clear it out. And you could see any crud building up in the filter.
They're still commonly available today, and inexpensive.

 

[grizzlyj]

There's also Guglatech in Italy who seem to be able to make a "sock" to suit most tanks depending on neck design, and then as long as your tank is deep. Not just for motos. They made two for me but yet to be fitted. Plenty of off the shelf for Motos or general jerrycan fitment.

 

[ChasingOurTrunks]

Thanks for the suggestions folks. I am going to look more into those filler neck options from Guglatech.

As far as a downstream filter goes, I think there's still value if only for the water separation. I'm also not totally sure what micron density the OEM filters would have; it may be excellent or it may be a glorified sieve. But, it's less of a priority than keeping stuff out of the tank to begin with.