This article was a collaboration between Jay Salser and Eric Shoemaker. As always, thank you Jay for all the contributions to 1967beetle.com. Your knowledge of these cars continues to amaze ’67 owners around the world.
The debate rages on over where to place a fuel filter. Even, whether or not to have a fuel filter in the first place.
There is a fuel strainer in the bottom of each VW fuel tank. This strainer is enough to stop large particles but fails the test of holding back fine particles and moisture.
Moisture! Every fuel tank accumulates some amount of moisture. When the tank is opened, ambient air, laden with moisture enters these vintage ’67 tanks. They are not sophisticated. Let’s face it, they simply are “holding tanks”!
Volkswagen owners began encountering the ethanol-gasoline fuel mixture and found themselves faced with a new problem. Ethanol and water latch onto one another and become one, passing right through the fuel strainer and into the fuel pump and landing in the carburetor. The strainer finally had met its match.
Well, complicate this with older tanks that began to have some rust issues.
There is a complicated explanation of how water and ethanol blend because the ethanol molecules are smaller than the water molecules. Given a mixture of equal parts of water and ethanol, the volume actually drops because the ethanol molecules fix themselves between the water molecules.
One of the major factors involves these old tanks which seldom get cleaned. If they already contain some moisture, which accumulates at the tank’s lowest point (where that strainer is installed), the ethanol combines with the water and drags the water and any tiny foreign particles with it through that strainer and directly to the pump and the carburetor—where it does its damage plugging tiny orifices.
When it comes down to it, an OEM fuel filter is necessary! These are German made, and metal lined at the screen, (not the cheaper version), and the perfect defense against modern day ethanol based fuels. Stop debris as small as 15 microns from reaching your fuel pump and carburetor.
Where to place the filter becomes the next issue.
The easiest solution is to place the filter between the fuel pump and the carburetor. It is easy to do and it is easy to monitor. But, because the filter adds a certain weight to the fuel hose at that point, combined with the constant vibration of the car’s movements, it is possible that the combination can lead to a loosening of the brass inlet tube to the carburetor until it falls out of the carburetor altogether. This almost always proves to be disastrous! With the engine running, fuel is pumping onto the hot engine case. And, there is the electrical sparking possibility. It doesn’t take much to ignite the fuel. The air being sucked into the engine compartment acts like a flame thrower. The end is fairly quick.
But, someone will be quick to point out that a barbed inlet can be substituted for the brass inlet tube, thus averting the possibility that the tube could ever come loose again. In fact, a barbed tube also can be substituted for the vintage fuel pump outlet tube.
Having a filter between the pump and the carburetor still opens the possibility for fuel hose failure. Instead of only two ends to the fuel hose, there will be 4 ends to monitor.
So…why take the chance with your beloved 1967 Volkswagen Beetle?
Not to fear! Moving the fuel filter out of the engine compartment is very simple!
- Raise the driver’s rear of the car, use a jack stand to stabilize the car and remove the wheel.
- Remove the heater tube. This will expose where the metal fuel line exits the chassis.
- It’s a good time to check the hose between the metal line from the chassis to the metal line into the engine compartment. Is it rotten? If so, you need to replace it. We stock the correct OEM cloth braided German fuel hose for your vintage pride and joy, the same as it left the factory long ago. A full fuel line replacement requires 4 – 7 feet, depending on if you are restoring a Beetle or Bus.
- If the fuel hose is in good shape, you need to clamp it off right where it exits the chassis. Good old vice grip pliers seem to work fine. Gas is a precious resource, why waste a single drop.
- Once it’s safely clamped, you need to cut the line in preparation for the filter installation. Don’t fear, you can do this. A little gas might run out, but don’t sweat it. I usually wear nitrile gloves. Oh, and I don’t advise smoking while you’re doing this.
- You can now insert the new filter between the two ends. We also stock the OEM German made fuel filters. Make sure you insert the filter with the arrow pointing towards the engine compartment. You may need to shorten the fuel hose a bit once the filter has been installed. Trim as needed and slip the hose onto the filter.
- MAKE SURE TO ADD FUEL HOSE CLAMPS. Yes, I’m yelling at you! You can also get the hose clamps for your engine area from us. These are the good OEM German type. Caution—do not over-crimp the clamps and crush the plastic filter tips. This will result in restricted fuel flow and possibly a leak.
Make a note to monitor your filter every time you do a tune-up.
Noting is worse than a really dirty one.
- It’s now the moment of truth. Turn the key, start the engine and watch fuel pass through the filter. Success!
- Reinstall the heater hose and bolt the wheel on.
- If you want to do a full fuel line replacement, including hoses and a filter. Here’s what you’ll need. 6-7 feet of Cloth Braided Fuel Hose, 10 fuel hose clamps, and 1 In-Line Fuel Filter. Again, all we have in stock.
Now, you won’t have to worry about this happening.
Lastly… your engine area looks a lot happier without the filter.
Now. Go outside and get that fuel filter out of your engine compartment! You’ll thank us. Feel free to email if you have other questions, etc. Or, join the conversation below.