1957 evinrude 5.5hp carb problem

[Jeremy1986]

i have a 1957 evinrude 5.5hp with new coils points condensors and rebuilt carb 2 new spark plugs and wires and new impellor. i have excellent spark and compression. the problem is i getting gas in the carb bowl and the shut off needle is working but the engine isnt sucking the fuel from the carb bowl. now i pour a little of 2 stroke gas in the carb she starts for a sec and then dies. please help i have the setting at low 1.5 turn and high at 1. any info will be helpful. thanks jeremy

 

[kbait]

Re: 1957 evinrude 5.5hp carb problem

If that one has the glass bowl underneath the carb bowl, it's likely a clogged filter inside that glass sediment bowl. Remove the filter and replace the glass bowl to test. Same thing happened to me. I bought a used filter from tim's outboard 218-682-2331 for cheap.

 

[samo_ott]

Re: 1957 evinrude 5.5hp carb problem

It sounds like it could be a pressure tank problem. Do you have the correct 2 line pressure tank? is the cap tight on the tank. When you push the primer button on the tank does it pump fuel into the bowl and get firm?

And what do you mean 'the shut off needle'? There is no such thing on that engine. Are you referring to the high speed and low speed adjustment needles?

btw, welcome to the iboats forum

 

[Jeremy1986]

Re: 1957 evinrude 5.5hp carb problem

hi guys thank for responding. there is no fuel filter in the glass bowl and the shut needle is the needle that the float push against to shut the gas off when bowl is full. i followed a website on how to convert the motor to a vaccum fuel pump. so i dont have the pressurized tank anymore. i have a single omc fuel tank.

 

[samo_ott]

Re: 1957 evinrude 5.5hp carb problem

Aha. Ok. Has it worked since you converted it? Did you use the Mikuni pump? Have you verified that the new system works?

Ok, so assuming you have fuel in the bowl and the float needle is open then if the engine is not drawing fuel you need to verify compression and or you might have reed valve issues.

But I go back to, are you sure the bowl is getting fuel properly with the new fuel pump?

 

[Jeremy1986]

Re: 1957 evinrude 5.5hp carb problem

what is reed valves

 

[Jeremy1986]

Re: 1957 evinrude 5.5hp carb problem

yes i used the Mikuni pump

 

[samo_ott]

Re: 1957 evinrude 5.5hp carb problem

The reed valves are behind the intake manifold and help to maintain pressure in the crankcase. They can bend, break or get plugged open with debris. If you don't have a manual it you should get one. I have the parts manual for the '56 5.5 which is quite similar. Send me a PM with your email address if you want me to email it.

 

[Jeremy1986]

Re: 1957 evinrude 5.5hp carb problem

i checked the compression and its reading 75# on both cylinders

 

[1946Zephyr]

Re: 1957 evinrude 5.5hp carb problem

75 on both cylinders huh? Sweet! Sounds like you have a nice motor here. Are both needles set right? Low speed, 1 1/2 turns out and High speed, 3/4 turn out? This is a good starting point for those. There's a possibility you make have to go into the carb and make sure a piece of debris didn't get into the float needle assembly or in the fuel passages.

 

[samo_ott]

Re: 1957 evinrude 5.5hp carb problem

75# is decent. But I'm still curious, has the engine ever run properly since you installed the mikuni pump? did this problem start afterwards or possibly as a result of the conversion?

 

[1946Zephyr]

Re: 1957 evinrude 5.5hp carb problem

Sometimes when you connect hoses, a nipple could cut a small chunk off the inside of the hose and send it down stream in the system and clog things up. I've had this happen a time or two. So I second samo_ott's point here. It wouldn't be a bad idea to post some pics here of the system, so we can see what ya got.

 

[Jeremy1986]

Re: 1957 evinrude 5.5hp carb problem

i never ran the motor with the pump i just got done overhauling the motor with all new parts now it wont draw gas with the new fuel pump and gas is in the bowl and when i take the bowl off and hit the primer it come out full pressure. but still wont draw gas

 

[Jeremy1986]

Re: 1957 evinrude 5.5hp carb problem

my carb has the glass bowl and that full of gas

 

[1946Zephyr]

Re: 1957 evinrude 5.5hp carb problem

okay, it sounds like the actuator in the pump isn't working properly, but at least your fuel flow is clean. The hose that feeds the actuator should be plumbed into a source of crank case pressure. I know these motors don't have bypass covers, so there would have to be another way of plumbing it in. I wouldn't use the connector on the intake manifold, because this sprays out fuel mix and could damage your actuator diaphram in your fuel pump.

 

[samo_ott]

Re: 1957 evinrude 5.5hp carb problem

Did you do the conversion where you plug one of the bypass lines behind the carb in the intake manifold? My guess is that you are not getting the pulse for the pump then. You need to revisit this part I believe. Although I have never converted one as I have lots of pressure tanks and have never had a problem with any on all my engines.

 

[Jeremy1986]

Re: 1957 evinrude 5.5hp carb problem

yes i blocked on of the holes to get a pulse vaccum for the fuel pump. can that be my problem. http://www.outboard-boat-motor-repair.com sad to block one of the holes to create a pulse vaccum.

 

[samo_ott]

Re: 1957 evinrude 5.5hp carb problem

Well is sounds like fuel is moving through the pump as it comes out when you pump it thus I still think it's the fuel pump/pulse.

Have you tried pumping it continuously (get a second person) and pull starting it and seeing if it will keep going while you manually pump it? This method will use a person to replace the fuel pump thus eliminating it.

And set the needle valves as listed above. 3/4ers of a turn out and 1.5 turns out.

 

[Jeremy1986]

Re: 1957 evinrude 5.5hp carb problem

hi steve
i think i have a block in the carb but i soaked the carb for 2 days in carb cleaner and blew it out all the jets when it came out and bought a carb rebuild kit for it but i pulled the drain plug ( the little brass screw on the side of the carb) and nothing came out and the same with the buttom high speed screw nothing came out but there gas in the glass bowl but i think it not getting up in the float area because i read that i pull the adjustment screw out gas should come out and nothing.

 

[samo_ott]

Re: 1957 evinrude 5.5hp carb problem

Yes, if you pull the drain plug out and/or the high speed needle (the lower one) fuel should come out, thus you are not getting fuel to the bowl. That should be an easy fix. Trace the fuel hoses and fuel flow as it should go right to the carb lower bowl. It must be something simple.