58 evinrude fuel system

[lymanboat15]

HI This is my first time on the forum I hope I get it right. I have a 58 35 hp big twin someone had a fuel pump system on the engine.I want to run the original two line system.There is a small line coming out from the front of the block behind the carb that is blocked off also a small ruber line on a fiting just above where the fuel bowel is suposted to be mounted also the lines from the carb are 5/16 to big to fit on the fuel filter also the wrong fuel fitting on the moter for the lines from the gas tank after I change that fiting to accept the two line system what to do with all the extra lines

 

[kfa4303]

Re: 58 evinrude fuel system

Hi lyman. Welcome to iboats. While you can certainly return the motor to a two-line set up, it may be more trouble than it's worth. However, if you still wish to make its stock, you'll also need to get a pressure tank as well as new fuel linew and fittings. You can find them easily enough on ebay and/or aomci.org. Here are some great links that explain the conversion. OF course, you'll simply do the job in reverse to put it back to stock.

General links:
Reviving a Vintage Big Twin - Part 1
1958 Evinrude 25937 35 hp Outboard Motor Parts

Fuel pump links. Do these in reverse to return to stock.
Converting the Old OMC Dual Fuel
HOW TO CONVERT 50s motors from two line tanks - YouTube

 

[F_R]

Re: 58 evinrude fuel system

OK,, here ya go....

The correct fuel connector is marked "Fuel" and "Air". A hose runs between the nipple on the bottom of the intake manifold to the "Air" side of the connector. Another hose connects the "Fuel" side to the inlet side of the filter bowl. A third hose connects the outlet side of the filter bowl to the carburetor. That's it.

You mentioned another hose (??). The only other one is for the vacuum cut-out switch. Connects the C/O switch to another nipple on the intake manifold, slightly higher up and toward the starboard side (still below the carburetor though). The cut-out switch prevents the motor from running wild in neutral. It'll make your hair stand up if it does that.

 

[HighTrim]

Re: 58 evinrude fuel system

There will also be the matter of the bypass cover. We will need to know exactly what modification was done. Was an OMC 2 barb pump used, or aftermarket 3 barb, or ???

 

[lymanboat15]

Re: 58 evinrude fuel system

Thanks everybody for the information .The hose I don't know about is coming out the side of the block just above where the fuel filter is mounted the hose for the cutoff switch is ok and hooked up the one in the front is the air supply for the tank right. how do I get from 5/16 hose to1/4 the nipple on the fuel filter is 1/4 is the niple on the carp also 1/4. the fuel pump was taken off the engine when i got the engine. boat moter and trailer was only $300.00

 

[nwcove]

Re: 58 evinrude fuel system

i just use 1/4 " clear line over the length of the nipple, then a bit of wd-40, and shove the 5/16 on over it. ( will be tight, but it works for me)

 

[F_R]

Re: 58 evinrude fuel system

Sounds like somebody has been doing more than a few modifications to that motor. The '58 Big Twin should have 3/16 hoses. The Lark is another story. Are you sure you don't have a Lark?

 

[lymanboat15]

Re: 58 evinrude fuel system

I,am sure its a bigtwin I had a lark this moter also has electric start . But that is another story The hose has 5/16 stamped on them .When they change over from a two line system to one line system are there any modefications made to the carb.

 

[HighTrim]

Re: 58 evinrude fuel system

Nothing to the carb no, unless someone tried to mount a Lark carb on it somehow? Can you post pics of this? You confused me as well when you mentioned 5/16" hose. As Frank stated, 3/16" for the 35hp. Is this aftermarket fuel filter you are referring to?

Also like I mentioned earlier, you may need to put in a different bypass cover if you now have one with a pulse hole drilled in it. Or block the hole.

 

[lymanboat15]

Re: 58 evinrude fuel system

After thinking my options over I have decided to keep the engine with the single hose setup I don't even know if the moter runs and just adding a fuel pump would be easiest.Now where and what kind of a pump do I use.Can I use a pump off a 1959 evinrude ,bolt it on and connect the hoses the engine came without a pump I have the tank, hoses and fittings.

 

[HighTrim]

Re: 58 evinrude fuel system

Could you not post some pics of what you have going on there? hard to guide you blindly.

 

[lymanboat15]

Re: 58 evinrude fuel system



Pictures of fuel lines also line that is pluged from carb

 

[lymanboat15]

Re: 58 evinrude fuel system

 

[lymanboat15]

Re: 58 evinrude fuel system

carb that is on engine

 

[F_R]

Re: 58 evinrude fuel system

OK, what you have there is somebody used an aftermarket fuel pump of some sort, most likey a Mikuni or
Briggs & Stratton. In any case, the hose coming off the bypass cover was the pulse hose to the pump. The other two hoses are fuel in and fuel out of the pump. You can do the same if you wish. OR you can use a pump that was made for the job. See those two holes, beside the pulse hose fitting? Tap #10-24 threads in those holes, then simply bolt a new pump to the cover, hook up the in and out hoses and you are good to go. Pump # 18-7351 or 18-7352 from here at iboats will do the job. 18-7351 has 5/16" in and 3/16" out. 18-7352 has 5/16" in and out. So that probably is the way to go, considering the carb fitting is as it is.

This picture shows what you are aiming for, albeit a different pump.

 

[lymanboat15]

Re: 58 evinrude fuel system

Thanks for the great info.There is a black wire coming from the cutoff switch that is not attached to anythinghing where does that go also is thsi the right carb. Also I have a ordered a manual from TC Outboard

 

[F_R]

Re: 58 evinrude fuel system

The cut-out switch appears to be wired incorrectly, at least as far as I can tell by the picture. Also, is the mercury switch on your throttle gear shot?? Here is how it is supposed to be.

I can't tell what the carb came off of. But it probably will work.

 

[lymanboat15]

Re: 58 evinrude fuel system

This moter was converted over to elect start i'am not sure if I want elEct or manual I don't remember how hard they were to start it was a long tome ago. Thanks again for the information there arn't many outboard places in the mountains of NC

 

[HighTrim]

Re: 58 evinrude fuel system

...and replace the screw in the bottom bypass cover where the aftermarket pump was likely mounted.

That cutout switch wiring does not look right as mentioned. Unless my eyes are playing tricks on me.

 

[lymanboat15]

Re: 58 evinrude fuel system

The fuel pump arrived today on the pump in the back the middle hole does a fitting screw into that hole the threads look very fine then to the vac. hose i'll need a spacer between the pump and engine to make room for the fitting.i'am probably making more of this job than it is.