84' 50hp evinrude problem

[Jude]

All, I have a recently rebuilt 50hp evinrude 1984
E50TLCR. Purrs like a kitten at low and high RPMs but it starves for fuel at 1/2 throttle. You get to half throttle and it starts to starve then nudge it very lightly and it takes off and runs fine beyond/below this point. I had someone look at it and said the float was cutting off fuel
at 1/2 throttle. They can't work on it for me so my question is how difficult is this to adjust and if so can someone point me to a procedure I can look at?
Regards

 

[fireman57]

Re: 84' 50hp evinrude problem

Welcome to iboats. I don't see how the float would cause this problem. If it is sticking and not letting enough fuel in for high range, it won't "unstick" and let more fuel in. Conversely if it is letting too much fuel in then it would be sluggish and flooded at low range until it burnt the excess fuel and could run normally at high range. I have an '83 of the same hp and it is easy to pull the carbs. I take my starter off for easier access. After you take the starter off (make sure you unhook the battery first) take the black airbox off. Undo the linkage and take the four nuts off the carbs. I leave the linkage that runs between them on. Turn them over and take out the four screws that hold the bowl on and there you are.
I would take them off and buy a kit for each one of them. They run around 20 bucks each at the dealer. rebuild them both. Soak them in a good carb cleaner and blow out every orafice with your air compressor or a can of compressed air. This is very important. Replace the parts with the ones in your kit. Set the floats so they are level when you turn the carbs upside down. Put everything back together. One more thing, chech and make sure that the butterflies in the carb throats open when the throttle cam roller moves off of it's mark. This is right above the linkage on your carbs. If you look up there you will see a little roller that lines up with some marks.

 

[steelespike]

Re: 84' 50hp evinrude problem

It appears there is a intermediate jet in the position where the Idle mixture screw is on older carbs.It's not clear if it is adjustable but it should be checked for clean and proper assembly.To me it isn't likely the float would cause only intermeadiate throttle problems.You should be working from a manual.

 

[Jude]

Re: 84' 50hp evinrude problem

Greetings and Thanks for the input Gents.
Manual is on the way from Iboats of course.
I will remove, clean and overhaul carbs as suggested.
Precise instructions guys, I really appreciate it.

 

[Jude]

Re: 84' 50hp evinrude problem

Gents...If anyone is still checking this thread I have a question that wasn't clear in the manual. If I rebuild the carbs and replace the componets supplied in the kit do i run the risk of burning up the motor because i may run the engine too lean? Not looking for absolutes here just
what to watch out for.

 

[steelespike]

Re: 84' 50hp evinrude problem

A normal rebuild should be no problem these carbs are
pretty straight forward.Just follow the procedures.
I've never seen anyone come on here and say they ruined their motor with a carb rebuild.
Your more likely to have a problem with a carb that needs a rebuild.

 

[fireman57]

Re: 84' 50hp evinrude problem

What steelspike said. The jets are fixed so there is no adjustment there. Just make sure that your floats are level with the carb body when turned upside down.

 

[Jude]

Re: 84' 50hp evinrude problem

Thanks guys, I see what you mean about the jets. I think I
may have stumbled on the problem. Upon removing the jets I found two different sized low speed jets in the top and bottom carbs. Both had #56D in high speed, both had #46 in the top rear jet but in the low speed on top of
the carb above high speed orifice I found a #35 jet in the top carb and a #30 in the bottom. The carbs were clean.
I am guessing this could be my half throttle problem?
Jude.

 

[Jude]

Re: 84' 50hp evinrude problem

Spike and Fireman...
I wanted to re-post this and get your input on the issue
I found with the different sized jets in my last post.
What are your thoughts? I have installed the same sized
jets now but haven't been able to test run yet. BTW the primer bulb would not get very firm before and now it firms right up as it should, I am guessing this is a good sign?
Jude

 

[fireman57]

Re: 84' 50hp evinrude problem

That is a good sign. The bulb should stay firm for a long time even if you don't start it. Once you do start it the bulb will soften some. This is normal. As far as the jets are concerned I saw where you posted that but do not have the OEM manual for your engine. I would run it and see how it does. You should be able to go to brpevinrude and pull up their engine diagrams and it might show the jet sizes. You can also call your local dealer and I'm sure he would be happy to look it up for you.

 

[romper]

Re: 84' 50hp evinrude problem

Might I inquire as to what manual you purchased? I have the same motor and would like to rebuild the carb, but am unsure as to a specific manual. The only one I saw covered 1971 to 1989. Is that the one you purchased?

 

[fireman57]

Re: 84' 50hp evinrude problem

I'm not saying anything bad about seloc or any other manual but pay the few extra bucks and get an OEM manual. They are available from Ken Cook. Just google it and you should find it. Lot more info in them and not as generic as seloc and the others. BTW you really went to an old thread. Nice search!