84 evinrude 4hp

[huntbirds]

I have an 84 evinrude 4hp that doesn't go into high speed. I have good gas going to the carb. as i put a clear tube from pump to carb and no air bubbles. Next I cleaned the carb, checked the float and al seems good there. So when I run the motor, it goes fine in slow speed, but when I throttle up it goes faster but not all the way. Maybe 50%. Then every once in awhile it revs up for a second then backs down tro the 50%. Any help out there?

 

[Daviet]

Re: 84 evinrude 4hp

Compression ok? Points clean and adjusted properly? Plug wires and plugs in good shape?
High speed nozzle and orifice cleaned when you rebuilt the carb?

 

[huntbirds]

Re: 84 evinrude 4hp

Compression seems good. I had new pugs put in by a mechanic recentley so I assume thats good. Plug wires look ok. Is the high speed nozzle and orifice that little tub inside the carb with two small holes in it? If so, then it has been cleaned.

 

[Daviet]

Re: 84 evinrude 4hp

#4 and 19 in the link below.
http://www.ishopmarine.com/ishop/js...CatFilter=BRP&eCatSupFldr=supplier-100-005-EJ

 

[SolingSailor]

Re: 84 evinrude 4hp

Possibly running on one cylinder? Check by pulling one spark plug wire at a time, then replacing. If pulling one makes no difference, that cylinder is not working.

 

[Daviet]

Re: 84 evinrude 4hp

Points clean and adjusted properly?
It sounds like you are dropping a cylinderunder load. You could use an inductive timing light to check spark under load and see if the ign system is working properly.

 

[huntbirds]

Re: 84 evinrude 4hp

Some one suggested I might need a coil?

 

[Rick.]

Re: 84 evinrude 4hp

When it isn't running well, pull on plug wires (be careful) one at a time to see if your only getting spark on one cylinder. They run very well on one but lack top end. If spark is good I would suspect the carb. isn't clean enough. Best of luck. Rick.

 

[Daviet]

Re: 84 evinrude 4hp

If you don't have spark on one cylinder, it COULD be a coil, or points, or condenser, or plug wire, or plug on the cylinder that is not firing.

 

[huntbirds]

Re: 84 evinrude 4hp

When I had it in a bucket it reved up fine but under a load, in the lake, it would not ramp up. Only about 50%

 

[Daviet]

Re: 84 evinrude 4hp

They will rev up in neutral, on one cylinder, a bad cylinder will show up under load.