You skip like a stone off the Sea of Cortez on the road south of San Felipe, Mexico. Broken pavement gives way to washboard road then two-tracks through bull dust and soft sand river washes. Travel is slow and meandering in Baja. When thoughts turn to diner, you claim a deserted beach or turn up an Arroyo to camp among Barrel, Boojum and Cardon cactus.
If you head far enough south you’ll find Coco’s Corner hidden deep in the desert; a legendary place for travelers and Baja racers. A glint of sunlight on the horizon becomes a fantastical collection of hundreds of dangling beer cans turned into pinwheels and reflectors. On the desert floor, random objects like toilets and car fenders are organized in geometric shapes that from space, I am sure, perfectly convey the magic of Baja in some universal language.
On one particular trip in Eore, our 1974 Land Rover, Michelle and I chatted with Coco in the shade of his single story, wood slat building. Nestled amongst camper shells and stripped 1970’s era pickups - every square inch holds Baja racing memorabilia, and the ladies undergarments, travel photos and stickers of passing travelers. Coco struggled to a pickup truck project parked nearby. An amputee, he leaned heavly on crutches while lifting the hood to reveal a standard American V8.
Of particular interest to me was the fuel line feeding the carburetor. Four inch sections of fuel hose connected a train of auto parts store plastic fuel filters - 8 of them in total. As Michelle cringed through one of Coco's piss-warm Tecate beers, she hates beer but respected the moment, we traded stories about contaminated fuel, vapour lock and clogged carburetor jets. Of the perils of refuelling from trackside surplus military trailers, discarded Baja race fuel jugs or weathered 1980’s Evinrude pumps pulling fuel from 50 gallon drums left unsealed against dust and tropical rain. Good times.
The fact is - you can pickup contaminated fuel anywhere, but the probability increases during remote travel. Bad fuel symptoms include lurching, stalling, lack of power, no-starts, misfires - and all at the most inopportune moments. Prevention is the key - and here is my advice for best practices.
Firstly, learn your fuel system routing and the components vulnerable to fuel contamination. On my Series Land Rover there is a fuel tank under each seat, a tank selector, a camshaft operated fuel-pump and the carburetor’s various jets. These are the parts to protect, and the parts you will need to clean if you introduce contaminated fuel.
The included photos of Eore’s main components provide an example of any fuel system’s primary vulnerability - tiny fuel flow aperatures. The carburetor pictured is the bottom half of a Weber 34ICH. In this specific carburetor the main jet is located in a recessed cavity in the bottom of the fuel bowl. Despite being a great design for maintaining off-camber fuel supply the main jet is left highly vulnerable to fuel contaminants. Cleaning requires separating the two halves of the carburetor with a steady hand to maintain float height and unscrewing the fiddly jet for cleaning with solvents or compressed air. Through the years I have performed this operation roadside on at least three occasions; once to organ pipes and the inspired chatter of an exiting church congregation. The repair was blessed, and I went in peace.
The second photo is the top half of a Series Land Rover camshaft driven fuel pump. These fuel pumps are famous in the Land Rover community for their shot glass sediment bowls. While perfect for Tequila with unexpected campsite company, I curse servicing the filter and have little faith in its filtering ability. Of note in this photo is the fuel inflow and outflow valves. With small apertures they are vulnerable to suspended solids in your fuel. While servicable on a Series Land Rover, most fuel pumps are not and will require part replacement once contaminated.
External Fuel Filtration. The photographed was purchased at a marine supply store; they are popular among Baja boaters. It is a three stage filter aimed at removing common suspended soilds from rust flakes down to fine particles. I would consider this filter a must for remote travel vehicles using in-tank fuel pumps. A pump submersed in your fuel tank will be impossible to protect with in-line fuel filtration. Repair will require draining the tank, and if the fuel pump requires servicing you may need to drop the tank itself to gain access.
I have, admittedly, used this filter on just three occasions. The fuel was purchased in desperate moments, and the sources were not regulated fuel stations. Regardless of the location of your fuel pump, consider some form of external fuel filtration for these moments. You may just roll into the Catavina, Baja Pemex on fumes to find no fuel and no scheduled delivery for a few days. There will be a guy down a dirt road outside of town selling petrol out of discarded Baja race cans for exorbitant prices - use your external filter on that swirling vortex of fuel and sand destined for your tank and ejoy smooth power on your journey.
Plastic in-line Filters These can be purchased cheap at any autoparts store and spliced into your fuel line - just ask Coco. Install them upstream from the vulnerable compontents you have identified. Transparent filters have the added benefit of providing a window into the flow rate, level of suspended solids or water in your fuel. Plastic in-line filters are inexpensive insurance and they are light and easily stowed spares.
Canister Fuel Filters I use Racor branded filters with 30 micron elements installed upstream from my pump and carburetor. In addition, I selected a fuel and water separating model with a drain port to purge collected water. Racor replacement elements are not cheap but sacrificial plastic in-line filters will extend filter change intervals. Still, carry a spare or two.
The Racor company provides a simple filter selector on their website that considers the fuel flow rate requirements of your vehicle. There is even a heated model for cold weather diesels. I have had good luck with Racor.
I hope this page will get you thinking about an often overlooked aspect of vehicle preparation. Once contaminated fuel is in your tank the symptoms can be maddeningly intermittent and will persist long after you have burned the offending fuel. For the vehihypochondriac - the resulting misfires and stalling will surely hint at imminent and complete engine failure making for a stressful trip. At a minimum, know where your OEM filter is and carry a spare or two.