Single vs dual fuel line?

[W_Guy]

When did Evinrude switch from the single fuel hose to the double one? My '58 Four Fifty has a single line. Pros & cons?

 

[lindy46]

Re: Single vs dual fuel line?

Actually, they switched from dual to single line in the middle of 1958 - early models were the dual line (pressure) tank and later models used a single line tank with a fuel pump. As I understand it, they switched for safety reasons (gasoline under pressure = bomb). I've had many pressure tanks/motors over the years and have never had a problem with them, and there is one less part to go bad (fuel pump).

 

[W_Guy]

Re: Single vs dual fuel line?

Thanks
My motor has a fuel pump and I'm not gonna change it. I'll just check the hoses and fittings under normal maintenance, just like my old cars. (none of them have burned down yet either)

Verne

 

[TLanglitz]

Re: Single vs dual fuel line?

I think the smaller motors didn't switch until 1960. I know my 1958 Sportwin is dual line, and the 59 sportwins I've seen online still had pressure tanks. My 35 hp 58 Johnson Super Seahorse is single line though.

 

[jay_merrill]

Re: Single vs dual fuel line?

I would switch any motor that I could to fuel pump/single line. Both the pressure tanks and the parts for them are harder to find than the non-pressure tanks. Motors that require a pressure tank also can not be easily switched to a main tank, if needed as a kicker.

The pressure = bomb thing is somewhat of a concern, but not as much as the practicality issue, in my opinion. Granted, the idea of an explosion is not one I take lightly, but when properly maintained, I don't see pressure tanks as a likely source of problem in that regard.

 

[coolguy147]

Re: Single vs dual fuel line?

i like it but u got to check the fuel pump every time it starts to act up and might need a new 10 dollar diafram. but pressure tanks arnt bad. i replaced the primer in mine with ned gakset and washers with the fuel lines. it works great.


the pressure tank had a feature that if the psi in side the tank i believe went over 7 psi it would open a valve to let air out

 

[freddyray21]

Re: Single vs dual fuel line?

in the late 50's it was an option that could be bought. I have owned two 57 Evinrude 18's. one with pressure tank and one with factory fuel pump.

 

[zebstarnes]

Re: Single vs dual fuel line?

All I know is I have owned my 1959 Fastwin 18hp for about 10 years. I use this motor on a weekly basis and the weakest link had always been the pressure lines. I rebuilt the tank twice and replaced the hoses twice and welded the tank once. In that time the only thing I had to do to the motor was change the impeller once and I purchased a new prop ( hit a rock). This winter I got with FR and we installed a fuel pump on it and I wished now that I had done ten years ago. I realize that the old duel line setup works ( and when it works it works really well ) but if your like me and you put an average of 10 hours or more a week on that system your going to be a lot happier with the fuel pump. It is just a more reliable system. Plus I can now use the same tank as my back-up fuel supply on my larger boat.

 

[jay_merrill]

Re: Single vs dual fuel line?

Zeb, I agree with you bigtime. I had a pair of '58 ERude 35hp motors on two different boats, and typically ran then like you do - many hours a week. I converted both to fuel pumps and was very glad that I did.

It was just too darn easy to do the work and then be able to use a pair of plastic Tempo, 12 gallon tanks that I had. I needed the fuel capacity for what I used the boat for, and being able to use the Tempos saved me about $400, that I would have spent buying 4 usable, 6 gallon pressure tanks.

To me, conversion is the only way to go, unless the boat is a restoration project that needs to have period authenticity. For the antique boat show guys, that is a big deal, so I understand their viewpoint.

 

[F_R]

Re: Single vs dual fuel line?

Here are the facts:

The 1958-59 50hp and the 1958-59 35hp Super Quiet / Lark had fuel pumps. The standard 35hp manual and standard 35hp electric start still had a pressure tank. It has nothing to do with "early" or "late".

They went to fuel pumps on all models in 1960.

It is also true that fuel pumps were an optional factory accessory on the 10 thru 35 horsepower motors before 1960.

The fuel pump truly came out in 1955 on Gale branded motors.

The old arguement about which is better will never be settled. Too many opinions out there.

 

[W_Guy]

Re: Single vs dual fuel line?

Thanks for the facts and pro & con opinions guys. After reading everything, I think I'm glad I have a fuel pump. Now I just have to make sure the rubber lines on the motor are changed to ones that will handle today's gas.
I also wonder about the fuel pump diaphram for the old girl. I'll bet those haven't been upgraded for modern gas.....

 

[R.Johnson]

Re: Single vs dual fuel line?

With a single line, or fuel pump engine, in an emergency, you could cut the tank connector off, stick the hose in a pop bottle of gasoline, and run the engine. A double line won't allow that. Double line tank as a pressure bomb. Any unvented gas gan in the sun will develop more pressure. The double line tank will blow off at about 4-5# as it has a pressure relief valve. The double line tank's now, if you use the available double line hose is of very poor quality in my opinion. It is a molded hose, not braided. If you insist on using this hose, open the cap when not in use.

 

[F_R]

Re: Single vs dual fuel line?

Thanks for the facts and pro & con opinions guys. After reading everything, I think I'm glad I have a fuel pump. Now I just have to make sure the rubber lines on the motor are changed to ones that will handle today's gas.
I also wonder about the fuel pump diaphram for the old girl. I'll bet those haven't been upgraded for modern gas.....

The diaphragm (kit) is available here at iboats. They should be ok for ethanol which has been a fact of life for a several years. The old one if it still is a '58 is due for replacement anyhow, ethanol or not.

 

[harp2822]

Some tanks have a little hand pump,some don't. What's the difference in the 2?