50hp evinrude, new problem, no WOT

[phatmanmike]

just got my 1980 50hp 2cyl repaired, it was the stator...has rebuilt carbs and new waterpump, all work done by shop were i purchased it...it takes a while to get it to start, like its some old 1963 ford pickup, but once it starts, i have to use the idle rev lever on the controls open all the way just to start it. when i use the idle rev lever, it doesnt really push the throttle back very far, is it supposed to be able to go WOT with that lever, casue it doesnt.and i put it in gear it dies, unless i switch reall quickly into gear, and once in gear, it wont even go high enough in rpms to plane the boat. boat is a 1986 bonito 16.5 foot CC. prop is brand newmichagan wheel aluminum 17 pitch..dont have tach yet, but motor is real quiet and top speed was no faster than the 40 foot sail boat we were running next to.. the fuel bulb does not get all the way hard, and the throttle plates do open all the way.. could this be fuel pump related.. any ideas thanks in advance !

 

[DHPMARINE]

Re: 50hp evinrude, new problem, no WOT

Good Morning,That idle lever (warm-up lever)advances the timing,and slightly opens the carb plates.Normal.Just curious...do both throttle plates open fully?One could be disconnected.As always....spark and compression OK both cylinders?<br /> DHP

 

[phatmanmike]

Re: 50hp evinrude, new problem, no WOT

thanks for the idle lever info.. both throttle plates are open fully 100 %.. new question, is it possible to have mixed up the throttle cable with the shift cable and its just not pushing far enough...or are the cable 100%interchangeable....

 

[rickdb1boat]

Re: 50hp evinrude, new problem, no WOT

It's possible, but real unlikely. Have someone Move the fast idle lever up and down while you look and see if it moves the throttle or shift lever. If it moves the shift lever, it backwards. Never had that question before!! Then have some move the main control lever all the way forward while you watch the linkage and see if the throttle plates open fully and timing plate advances all the way. And Just another thought, Broken or frayed cable???? And another, Remove the throttle cable from the carb and manually try to open the carb plates with the lever the the cable connects to and see if they open all the way and that the timing plate goes all the way to it's stop.

 

[phatmanmike]

Re: 50hp evinrude, new problem, no WOT

^

 

[rickdb1boat]

Re: 50hp evinrude, new problem, no WOT

Did you try any of the tests???

 

[phatmanmike]

Re: 50hp evinrude, new problem, no WOT

just got back from water test... at home on the muffs... boat starts easy and idles fine, and when put in gear, it goes up there into the rpms WAY higher than in water.. in the water, once boat is started..it stumble at idle and stalls unless i rev it up, and at WOT it only goes about 8-10 mph, just a tad bit faster than a 40 foot sailboat going through the channel next to us... do i have it over propped? the prop size is 13 diamater by 19 pitch, i know my post signature says 17, but its atcually 19.. the i boats store recamends 11 or 13 pitch and 11.5-12-5 diamater.. what do you think

 

[phatmanmike]

Re: 50hp evinrude, new problem, no WOT

just wanted to add that boat weighs 650 lbs and motor weighs 200 lbs plus 12 gallons gas and 450lbs worth of people(3)<br />1300 lbs plus a few here there..

 

[Solittle]

Re: 50hp evinrude, new problem, no WOT

phatmanmike - I'm curious why you don't have the dealer who you bought it from and did a bunch of work on it fix it? And yest I think you are way overproped - you need a tach to get this right or go to a prop shop and tell your story. They should be able top nail the right prop for you.

 

[phatmanmike]

Re: 50hp evinrude, new problem, no WOT

the dealer is in pok city, near orlando, and i am in pinellas county in the gulf beaches area, 86 miles each way, thats why, so im trying to figure as much as i can before i have to " take the drive ". going to prop shop tomorrow... will post more L8R

 

[ob15]

Re: 50hp evinrude, new problem, no WOT

I'm not sure if the gearing is the same, but I have a 1980 Evinrude 50hp on a smaller and lighter boat (15' 200 lbs +/-lighter) & i think my best prop choice is a 11 3/4" dia x 17" pitch. A 13" dia & 19" pitch is way too much. A tach will help a lot.

 

[jimchere]

Re: 50hp evinrude, new problem, no WOT

I'll add to what Dave said that may help you get in the ballpark. I'm running a 16' glass center console, about the same weight as yours maybe 100-200lbs heavier. With my '82 55hp Evinrude 2cyl on the back it runs just about right with an 11 3/4" diameter and 15" pitch prop (I have the non-commercial gearcase). It runs about 5000rpm at wot and speed by GPS about 28-30mph depending on weather.<br />Edit: More info on the prop. It is an OEM Evinrude aluminum 3 blade prop, and appears to have some mild cupping on the trailing edges of the blades.

 

[rickdb1boat]

Re: 50hp evinrude, new problem, no WOT

11 3/4" diameter and 15" pitch prop would be real close on your set-up. It still would not account for going only 10 MPH now though. Unless of course, it never planes out. I hate to keep running it in the ground, but did you ever get a chance to troubleshoot any of the ideas I gave you?<br /><br />

It's possible, but real unlikely. Have someone Move the fast idle lever up and down while you look and see if it moves the throttle or shift lever. If it moves the shift lever, it backwards. Never had that question before!! Then have some move the main control lever all the way forward while you watch the linkage and see if the throttle plates open fully and timing plate advances all the way. And Just another thought, Broken or frayed cable???? And another, Remove the throttle cable from the carb and manually try to open the carb plates with the lever the the cable connects to and see if they open all the way and that the timing plate goes all the way to it's stop. <br />

we need to know if the motor is running right first, before propping comes into the equation..

 

[phatmanmike]

Re: 50hp evinrude, new problem, no WOT

motor runs excellent out of the water.. starts, idles in nuetral and in gear, but once in the water, it idles in gear but is reall stumblish( if that is a word)stumblish ...wen in water and put in gear at wot, only goes about 10mph and doesnt rev very high at all and does not get on plane !and throttle plates are 100%open(i checked) at home with plates 100%open motor just screams waaaaaaaaaaaaaaa aaa aa a a a a a a a ,,, just like its supposed to !<br /> the prop calculator i found through another post recamends a pitch of 13 with diamater of 11.5 or 11.75, which is waayyy off what i have now, there is a local prop shop near by, im gonna try them today.. will post L8R prop calculator

 

[rickdb1boat]

Re: 50hp evinrude, new problem, no WOT

Do not rev the engine way up in neutral, unless you want to but another! I still don't think the prop is your problem, but ya never know.... I'd go with the 15", as you can always re-pitch it for a nominal fee. They may even let you test one out if you ask nicely and return it in the same shape you got it in. Good luck and let us know how it turns out. Hope I'm wrong about the prop being the problem....

 

[ob15]

Re: 50hp evinrude, new problem, no WOT

Just a thought. The size of the prop could also be straining the motor too much in the water at idle seeing as how you can't get any speed out of it. using a smaller prop might take care of the problem.

 

[steviecops]

Re: 50hp evinrude, new problem, no WOT

Look. I'm an extreme novice at outboards, but I've got a few ideas. I'm sure someone will tell me if I'm wrong, and that will also help my education. Please don't shoot me, but here goes.<br /><br />Is the engine positioned on the transom properly? ie, is it set too low and causing too much back pressure through the exhaust? We have problems like that with our old British seagull outboards.<br /><br />Or, is your hull foam filled, and could it be water logged?<br /><br />Sorry if I'm way off. Just trying to be helpful ;o)

 

[phatmanmike]

Re: 50hp evinrude, new problem, no WOT

ok took boat to boat ramp without prop, put in water.. idles great and revs great, pulled up and put prop on , put back in, stalls and wont rev.. bought new prop"12.5 x 13 pitch " revs great and even gets on plan a lil, still working out some bugs, like good tilt settings and such, but fixed the big problem... thanks guys... now if i could only stop it from revving up once i get to WOT, as if the prop was slipping.. gonna go check some older posts on this site... and thanks to all.. when i figure it out.. ill re post what the progress is so all can learn from my missfortune !

 

[ob15]

Re: 50hp evinrude, new problem, no WOT

Glad to here your getting things worked out. Keep us informed.