1950 4438

[Missyb]

Hi there I inherit ed an evinrude 4438 14 hp motor however I got no tank!!! Or line. I would love to do the conversion on it but I can't find any info just 1955 and younger. Is it even possible? Am I in way over my head?

 

[F_R]

I suppose it is possible if you are determined enough. But why not just find a good pressure tank, as it was designed for?

 

[kbait]

You can use a standard single-line tank hooked directly to carb for testing..prime (fill) the carb bowl to run briefly. Elevate tank above carb, and carb will stay full (gravity feed). When you know it’s a runner, add fuel pump.. lots of info out there, or check back.
That said, if you can find a good pressure tank…
Good luck!

 

[Crosbyman]

here is a bit of info . you can mod. with the blocked channel method and use the modified air pressure nipple or do the pump on aplate method watching clearance with the hood or.. you can do the vacum nipple threaded on a side cover . If you can find a more modern side cover with the fuel pump molding just swap the cover and mount a pump. In summary you must get a vacum pulse source to run the pump and find yourself a single line connector to replace the 2 line connector engine side. Before you start ..do compression , check coils for cracks , gearcase for water leak etc... etc...

 

[F_R]

Yeah, good point. Evaluate that thing before spending your coins. That was the old slab-sided block, tough enough, but "different" Not 100% sure, but I think it has the old 550040 coils that were made of unobtanium and melted within the first 2 or 3 years' life. Installing a fuel pump is an easy job, compared to dealing with the ignition system.

 

[Missyb]

I suppose it is possible if you are determined enough. But why not just find a good pressure tank, as it was designed for?

Because apparently the pressurized tanks are like sitting bombs lol. If a hot piece of sheared metal comes down that air line to a pressurized tank full of gas .... kaboom lolol or so I have heard

 

[Missyb]

here is a bit of info . you can mod. with the blocked channel method and use the modified air pressure nipple or do the pump on aplate method watching clearance with the hood or.. you can do the vacum nipple threaded on a side cover . If you can find a more modern side cover with the fuel pump molding just swap the cover and mount a pump. In summary you must get a vacum pulse source to run the pump and find yourself a single line connector to replace the 2 line connector engine side. Before you start ..do compression , check coils for cracks , gearcase for water leak etc... etc...

I have watched all these videos the one thing I'm confused or worried about is the whole bypass cover plate thing or putting an air line into the carburetor. Can I not just use the air line that is already there coming g off the manifold to power my pump?

 

[F_R]

"Because apparently the pressurized tanks are like sitting bombs lol. If a hot piece of sheared metal comes down that air line to a pressurized tank full of gas .... kaboom lolol or so I have heard" Oh, c'mon now, that ain't about to happen. Besides, so-called non-pressurized tanks also build up pressure when sitting in the sun.

To answer the direct question, no you cannot use the tank pressurizing line to power a fuel pump. A fuel pump requires alternate pressure/vacuum pulses to move the diaphragm back and forth. The present pressure line is just that--basically a constant pressure.

The slab sides on your 14hp are not swappable for the newer bypass covers. Also, do not remove those side covers except as a last resort for some reason. They are very difficult to reseal.

 

[Missyb]

"Because apparently the pressurized tanks are like sitting bombs lol. If a hot piece of sheared metal comes down that air line to a pressurized tank full of gas .... kaboom lolol or so I have heard" Oh, c'mon now, that ain't about to happen. Besides, so-called non-pressurized tanks also build up pressure when sitting in the sun.

To answer the direct question, no you cannot use the tank pressurizing line to power a fuel pump. A fuel pump requires alternate pressure/vacuum pulses to move the diaphragm back and forth. The present pressure line is just that--basically a constant pressure.

The slab sides on your 14hp are not swappable for the newer bypass covers. Also, do not remove those side covers except as a last resort for some reason. They are very difficult to reseal.

Ahhh maaaan........you just killed all hope and dreams I had dam it! Lol.

 

[Missyb]

"Because apparently the pressurized tanks are like sitting bombs lol. If a hot piece of sheared metal comes down that air line to a pressurized tank full of gas .... kaboom lolol or so I have heard" Oh, c'mon now, that ain't about to happen. Besides, so-called non-pressurized tanks also build up pressure when sitting in the sun.

To answer the direct question, no you cannot use the tank pressurizing line to power a fuel pump. A fuel pump requires alternate pressure/vacuum pulses to move the diaphragm back and forth. The present pressure line is just that--basically a constant pressure.

The slab sides on your 14hp are not swappable for the newer bypass covers. Also, do not remove those side covers except as a last resort for some reason. They are very difficult to reseal.

If I was to put the air line through one of those slabs I would not even have the slightest clue where to put it
.