Making My Own Biodiesel-Compatible Cigar Hose
 

I run B99 in my car and since I have either the option of replacing the cigar hose every couple of years (it's been over 4 years on what appears to be the original aged, hardened cigar hose using B99 with almost every tank, no leaks yet) or using a straight hose with risk of the hose being stressed from the fuel pulsations, I have considered making my own cigar hose.

I was thinking of using biodiesel-compatible hose (in my experience the factory hoses have lasted longer using biodiesel than the plastic-lined hose, though), then using a couple reducer barb fittings so I could go from a 5/16" hose to maybe 1/4" and then back to 5/16". Does this sound like it will do the same thing as a cigar hose?

I just read that brass isn't compatible with biodiesel, so using brass reducer fittings wouldn't be a good idea.

Correct me if I'm wrong, but isn't the middle of the cigar tube hose larger, rather than smaller, than the end portions?
That way, it acts like a damper, no?

cigar hose
 

I believe the cigar shape was a sound deadening design. I have done a lot of oil and I would suggest you get 3/8 Pex Line and use that. Heat up the end (I use a blow torch) and push as far down return steel hose as you can. Make sure to leave a little give so that it can shake. Then attach to the top of the filter fitting. Make sure you get a good seal and you are ready to go. If you can find 1/4 in Pex you can use it for most of the other fuel lines. Except the one that does not have barbs on it. The PEX will not stick to that one.

Yeah, I meant for it to go from 5/16" to a much larger size and then back to 5/16".

PEX sounds interesting. I'll have to research it.

I'm not sure you even need the cigar hose. I've been running plain old fuel line on mine for the past 50k miles with no known ill effects or issues.

A third option is to loop an extra foot or two of B99 rated line in place of the cigar hose. It's just there to dampen pulses from the IP.

I've noticed that the OM603 engine doesn't use a cigar hose, but rather a fairly long piece of hose. My OM621 used a 3/8" hose.

Gates/NAPA 'Barricade' brand hose is biodiesel compatible. Good quality biodiesel will not react with brass.