Fuel Filter

[Pitti Biofuels Forum Newbie Find all posts View Profile Close Pitti]

Hi all,
I'm running my Izuzu Bighorn (1995) on my home made biodiesel. I read that it is quite normal that you have to change the fuel filter at the beginning. The first one lasted about 2000km and the second about 5000. Any experiences if that will improve? Are there any other filters available which accomodate the use of biodiesel better? I'm pretty confident my product is of good quality but nevertheless any suggestions what (apart from old stuff in my tank) could be the source of evil are very much appreciated. Is it only sludge or grease or could viscosity be an issue?
I'm driving lots of km a week on dusty roads in the middle of nowhere - so braekdowns are no fun.
Can't even do the helpless girl game, cause there's not much traffic around.
Petra

[Tony From West Oz Vice Chairperson of WARFA Find all posts View Profile Close Tony From West Oz]

Re: Fuel Filter

Petra,
The main things which will block your filters are:

• Diesel residues from the fuel tank. These will eventually be cleaned out by the biodiesel and should not cause long term difficulties.
• High melting point biodiesel. This is formed when high melting point oils are used to make biodiesel. Do the refrigerator test on your biodiesel to see if this will be an issue with your biodiesel. If the best oil you can get still get has a lot of high MP oil, you may be justified in installing fuel heating in the vehicle, to overcome this issue.
• Byproduct. If the biodiesel is poorly made, byproduct can settle in the bottom of the fuel tank and be sucked into the fuel lines and possibly cause filter blockages or even injector pump damage.
• Other contaminants. If your fuel handling allows contaminants to enter your fuel and not be filtered from it.

Regards,
Tony

[Pitti Biofuels Forum Newbie Find all posts View Profile Close Pitti]

Re: Fuel Filter

Thank you Tony, I'll try that. Any advice on how to test for 'byproducts'?
Petra

[Tony From West Oz Vice Chairperson of WARFA Find all posts View Profile Close Tony From West Oz]

Re: Fuel Filter

Take a sample, allow and byproduct to settle to the bottom of the container. The byproduct is the glycerol, soaps and other stuff which separates from the biodiesel during production.
Although it can and will burn, it is not suitable for use as a diesel fuel, and being slightly caustic can cause corrosion of aluminum fuel system parts.

Byproduct removal is normally done by settling then washing the biodiesel decanted from above the byproduct. The byproduct has an affinity for water and washes out easily, although emulsions can form if washing is too vigorous.
It is also possible to cause remaining byproduct to drop out of solution with the unwashed biodiesel, by recovering the methanol from the biodiesel and allowing additional settling time.
I hope this helps,
Tony

[Pitti Biofuels Forum Newbie Find all posts View Profile Close Pitti]

Re: Fuel Filter

thanx again Tony, but I'm doing all this. I wash the BD and it is clear before I store it. It passes the Methanol test - no problem. I also let it sit quite a long time (4-6 weeks) before using it. Was just wondering if there are tests for soap residues or the amount of water particles still bound by probably some excess methanol? I've got a fair understanding of the chemical process involved but unfortunately not much about cars. My mechanic is all negative about BD and comes up with all sorts of scenarios. Anyway didn't stop me so far - just don't like to break down at the side of the road a lot. It's also not that easy to change the filter in my Izuzu, so I'm not too keen on doing that myself.
Would it be possible to create some sort of 'bypass' around the filter, so if it blocks I can at least make it to some civilized area?
What about additives? Tried to search for this but theres not much here.
Petra

[speaksgeek Biofuels Forum Newbie Find all posts View Profile Close speaksgeek]

Re: Fuel Filter

Have you installed a second inline fuel filter before the main one?

It may be worth doing so, and then you can try and locate it in a spot that's easier to access than the main one.