'56 Evinrude Fleetwin Carburetor Adjustments

[bjarnold]

I was wondering what the factory high speed and low speed adjustments are for a 1956 Evinrude 7.5 Fleetwin. Also, I am running the motor on 24:1 (half pint of oil per gallon of gas)but the motor smokes really bad and in neutral the motor will run at wot but with it in forward gear it does not reach wot it just seems to run to rich.<br /><br />Bill

 

[OBJ]

Re: '56 Evinrude Fleetwin Carburetor Adjustments

Hi Bill<br /><br />Try this, run both needles in until gently seated and back out about 3/4 turn. With the motor on the boat and in the water, warm it up and run at WOT and set the high speed needle, turning clockwise first about 1/8 turn at a time until you get best speed. Come back down to idle in gear and do the same with the low speed needle until you get best idle. Back the low speed needle out slightly after best idle speed to prevent a to lean condition. If the carb is clean and not malfuntioning, you should see a difference in the speeds as the adjustments are made. If you are using a good brand name TC-W3 oil for gas mix, you don't have to mix it that heavy but do not go below 50:1 mix.

 

[alcan]

Re: '56 Evinrude Fleetwin Carburetor Adjustments

Hi Bill<br />I have to respectfuly disagree with Jim. 24:1 is the correct fuel/oil ratio. A half pint to the gal. does work out to be a little on the rich side. A quart to six gals is just right. These older motors need the extra oil to help in sealing the main bearings on the crankshaft. Don't short the oil. As for the smoke, they should smoke a little, and I guess by todays standard a lot. If how ever your motor is tuned and adjusted properly you will barely notice the little extra smoke. Starting setting for the needles is 3/4 turn out on the high speed and 11/2 turns on the low speed. Then procede from there as Jim states. I have a copy of a priod owners manual, it's not for your exact model, but the info is transferable to yours. If you would like a copy post your E-mail adress and I'll try to shoot you a copy.

 

[rolmops]

Re: '56 Evinrude Fleetwin Carburetor Adjustments

I'm with Alcan.

 

[bjarnold]

Re: '56 Evinrude Fleetwin Carburetor Adjustments

Thanks for the replys but I am still wondering why it will reach full throttle in neutral but not in forward gear.<br /><br />Bill

 

[alcan]

Re: '56 Evinrude Fleetwin Carburetor Adjustments

Hi Bill<br />Uless important parts are missing your motor can not turn-up full throtle in neutral or reverse. There is a sort of built in safty stop. You may have several little problems with this motor that a tune-up and service sould cure. Sounds like the carb may be gunked up and maybe the points need cleaned and adjusted. If this unit has the orignal ignition coils still, I'd be almost willing to bet they are moldy and split.My E-mail adress is alcan.fixit@verizon.net, last chance for FREE info including pictures.

 

[OBJ]

Re: '56 Evinrude Fleetwin Carburetor Adjustments

Bill....<br /><br />Take alcans advise....ya' won me over alcan...LOL..25:1 it is......

 

[bjarnold]

Re: '56 Evinrude Fleetwin Carburetor Adjustments

Alcan,<br /><br />My e-mail address is bjarnold@caltel.com<br /><br />Thanks<br /><br />Bill

 

[Chinewalker]

Re: '56 Evinrude Fleetwin Carburetor Adjustments

Just a point of note... The 7.5s and 5.5s did NOT have a neutral rev limiter like the 10hp and up Johnrudes of that era.<br /><br />It is highly likely that in this case that the motor is only running on one cylinder. ANY motor will SOUND like it is revving fine in neutral with no load on the motor. Check for spark. In all likelyhood, the coils (if original issue) are cracked. Pull the recoil and remove the access plate on top of the flywheel. If the coils are chalky looking or cracked, replace them with new. You can replace everything under the flywheel for about a $50 bill and you won't have to worry about it again in your lifetime (other than perhaps a point setting and cleaning every other season or so).<br /><br />Also, if you don't know when the impeller was last replaced, replace that, too... All these parts are available at NAPA, and possibly your local Johnrude dealer if the parts guy is feeling helpful...<br />- Scott

 

[bjarnold]

Re: '56 Evinrude Fleetwin Carburetor Adjustments

Chinewalker,<br /><br />I checked both cylinders and they are getting a good spark. <br /><br />Bill

 

[Chinewalker]

Re: '56 Evinrude Fleetwin Carburetor Adjustments

Hi Bill,<br /> Is that in the open air or while running? Often you can get a good spark in open air, but under the added resistance of a compressed air environment it'll break down. Check for spark with the motor running - remove one wire and ground to the block. Start the motor and note any difference from previous with both wires connected. If motor won't start at all, then it's likely the removed one is the one it was running on...<br />- Scott

 

[bjarnold]

Re: '56 Evinrude Fleetwin Carburetor Adjustments

I checked the spark with the plug out. I did notice that the low speed needle was backed out 3 turns so I adjusted it to 1 1/2 turns out and it seems to run smoother and idles slower. And it will start on the first pull without starting fluid. I am wondering if the carburetor is all gummed up that is why it will not reach full throttle in gear. <br /><br />Bill

 

[bjarnold]

Re: '56 Evinrude Fleetwin Carburetor Adjustments

Chinewalker,<br /><br />I pulled one spark plug wire off and the motor would not even try to start. I put the wire back on and pull the second one off. The motor would not start again. After putting both wires back on the motor fired right up. <br /><br />Bill

 

[bjarnold]

Re: '56 Evinrude Fleetwin Carburetor Adjustments

^

 

[alcan]

Re: '56 Evinrude Fleetwin Carburetor Adjustments

Hi Bill<br />What can we do for you? Did you remove,disassemble,clean and readjust your carb? Did you Check your ignition coils? Are they in good shape? Did you clean an readjust the points? How about your tank and fuel line connector, are they in good shape? Can't give you an answer without a question.

 

[bjarnold]

Re: '56 Evinrude Fleetwin Carburetor Adjustments

I took the carburetor off and took it apart,cleaned it, re assembled it,adjusted it and put it back on. I checked the gas tank and there are no air leaks. The engine looks like new with low hours so I seriously doubt that the coils could be bad but I will check them anyway.<br /><br />Bill

 

[alcan]

Re: '56 Evinrude Fleetwin Carburetor Adjustments

Hi Bill<br />The over all condition of your motor has nothing do do with the condition of the coils or points. If this motor still has the original coils in it, odds are better than even they are cracked or split. Coils with this condition will alot of times produce good spark in the shop,in the tank, under realatively dry conditions. Put this same motor on the back of a boat in a lake and you've got a problem. Looking at the tops of the coils thru the inspection hole in the flywheel only tells half a story, The bottom side of the coil is where they tend to short out. Also the points over years,sometimes just a year can corrode or get weak in the springs, the rub blocks can wear also. Will your motor respond when you adjust the needles? Have you had a look at your water pump empeller? Is the motor over heating? To test dip a hand full of water and drizzle over the head and cylinder area. If the water droplets sizzle and dry real fast it's too hot. If they sort of roll around and steam a little and dry slowly your good to go. Also there is a small gasket inside the carb bowl. this gasket is on the main nozzle. They tend to dry and become brittle. If you don't have a good seal here the motor will run rich and will not respond to needle adjustments. make sure your packing nuts on the needles are snug as well.