I want to add an external gas tank to my evinrude 4.5hp

[scfisherman]

I want to know if its possible to add an external gas tank to my evinrude 4.5 hp outboard model E5RCSS, its a 1980 model with the internal tank, is there a kit? I understand that evinrude made 2 different models of this motor, one with the extrnal tank and the other with the internal tank. I would like to convert to the external tank, but dont know what parts I need to do this, any help with this as to fuel pump number and connectors would be greatly appreciated!

[boats.net]

Would have to replace fuel pump,
0397445 Fuel pump
0393334 Fuel Connector
0313117 Bolt

[scfisherman]

replace the fuel pump?

this 1980 4.5 is the model with the internal gas tas tank its gravity feed, there isnt any fuel pump on it right now! Are you saying this fuel pump will bolt to an existing place on the motor, and if so where?

[boats.net]

If your specific engine does not have one equiped you will need to install one, those models did have fuel pumps.

[scfisherman]

1980 e5rcss 4.5

when i punch up evinrude 1980 e5rcss fuel pump, the model number 0397445 is not listed for this engine there,it lists a different model number, actually (2) for a 1980, 4.5... is this a general fuel pump for my engine? I absolutely want to order the right parts for this engine, and dont mean to be a pain. I understand they made 2 different models of this engine...one with a internal fuel tank under the cover (gravity fed), and the other with a external fuel tank.....are you correct with the model numbers you sent me?

[boats.net]

The parts previously supplied are correct. There are two different pumps, one for integrated fuel tanks the other for external fuel tanks. The number previously supplied (is the superceeded number) is for the external fuel tank.

[scfisherman]

fuel pump location and fuel pump size hoses

I recieved the parts saturday and immediately looked into locating the fuel pump to the engine. It appears the only place, that coincides with the screws supplied, for mounting, that there is a hose and nipple, coming from the center of that location, that runs from there to the carburetor, next to the fuel inlet hose to the carburetor. After looking at the all the 4.5 intake manifold diagrams, it appears this nipple and hose, it called the pump pulse hose, so i cant mount the fuel pump there. Also the fuel pump supplied has 2 different nipple sizes, the IN being a larger diameter, which I ***ume will come from the fuel tank.hose.., then to the OUT nipple to the carburetor, 3/8 nipple to 1/4 inch nipple out. The fuel input nipple on the carburetor body however is 3/8 size! Am i to just use a 3/8 fuel hose, on the 1/4 inch pump outlet with a hose clamp, or is there a part thats missing ??Help!!! Location of the pump and hose sizes? Also this pulse hose nipple on the carburetor has a fuel pump bladder in the carb already, am i supposed to leave this all intact, or just plug the pulse hose?

[boats.net]

It looks like there are two different carburetors. Try hooking up without modifying the carburetor.

[scfisherman]

Hooking up....Where? What about the different hose sizes?

Theres no place to attach the fuel pump on the engine block except where the pulse hose is. The fuel pump has a 3/8 IN and a 1/4 inch outlet, but the fuel in on the carb, is 3/8 inch, what do I do about that?

[boats.net]

You can try and change the carburetor inlet to 1/4" or use 5/16" fuel hose and hose clamps. The fuel pump should mount the same as the original fuel pump. Unfortunately I am not 100% familiar with your specific model.

[scfisherman]

fuel pump mounting

Well youre incorrect! The mounting holes where the fuel pump should be regularly mounted are there, however, in the center of this location there is a nipple with the pulse hose coming out of it, maybe I can put a spacer in the location and try mounting the pump off axis by onle one screw and add a homemade bracket to the other! There is also the matter of the the fuel inlet on the carburetor, whish right now is going to a fuel filter and then the internal tank. Underneath the pulse hose fitting in the carb, there is a bladder (fuel pump for the internal tank). I will first try, plugging the fuel line from the internal tank, with an adequate size bolt, then i will run the external tank line directly to that fitting on the carburetor, using only the primer bulb, and NOT the fuel pump at all! If there is adequate suction for fuel to enter the carburetor, using only the bladder, you will get the fuel pump returned to you, for a refund! I will put the motor in a garbage can filled with water and run it for atleast 25 minutes, which is more than the time it takes to drain the internal tank if it were hooked up....if it continues to run, I WONT NEED THE FUEL PUMP, if it doesnt then I will persue locating the Fuel Pump you sent me aternately.

[boats.net]

If that does not work remove the pulse nipple and mount the fuel pump in its proper location. There should be a gasket that seals the fuel pump to the block.

[scfisherman]

back side of the fuel pump supplied

I will persue hooking up 5/16 hose instead....thankyou! Question.....On the back side of the fuel pump we ordered there is a small opening, are you saying that a gasket needs to seal this pump to the place where the nipplle is located, what is the purpose of the gasket and how does the carburetor get its pulse for the bladder then?

[scfisherman]

Finally>>>SUCCESS!!!!!

After trying every concievable approach to getting this external gas tank to work....this is what I did: First of all 5/16 inch fuel line is way to big!!!! 1/4 inch fuel ine throughtout the installation from the tanl to the fittings, fuel filter, and fuel pump and back to the carburetor. 1-remove the pulse nipple, I made my own gasket from rubberized gasket paper and a razorblade. This gasket is key to the fuel pump pulsing, otherwise it will flood the caburetor. the gasket goes between the fuel-pump and the manifold where the pulse nipple was, on the back of the fuelpump there is a hole that connects to the internal diaphragm of the fuel pump, this seal is crucial to proper operation of the pump. 2- mount the pump, attach the inlet from the external hose connector, two holes must be drilled in the lower body of the engine cowl to mount the connector with the supplied bolt and star washer. 3- Inside the lower engine cowl at the connector use the existing fuel filter from the internal tank and route the fuel hose just behind the fuel bowl to the other side of the engine and into the fuel pump IN, then connect another 1/4inch fuel line to the OUT of the fuel pump to the carburetor input nipple, (I used a small cabletie around the nipples to insure a good leakproof seal), 4-I used a small 1/4 inch stainless bolt to plug the pulse hose, which used to be hooked up to the pulse nipple which was removed to facillatate mounting the gasket and fuel pump. Leaving this hose unplugged makes the carburetor surge and high speed, so i plugged it and tucked it away in the lower engine cowl. Voila!!!!! It runs great......the primer bulb stays hard and filled with fuel, and it starts on the 1st pull everytime. A few visits to the local Evinrude Dealer helped me to copy the fuel line routing in the lower engine cowl. As for the internal tank....well I plan to remove it, and make up a fibregl*** patch for the top of the engine cover, gives me more room, to access the spark plugs and coils and the bracket that held the tank is now a toolkit bracket, for emergency on the water fixits! Thankyou so much for all of everyones help!!!! Karl (SCFisherman)

[scfisherman]

a little more pep in the engine

we took the engine through its paces yesterday on the big water in lake murray, it seems to have a little more pep, virtue of a real fuel pump and not just a bladder!