55 hp Chrysler half throttle? Please Help!

[Seleronn]

With prop engaged, my 55 hp only has half throttle at best. When you put the leg in neutral, it will go full throttle, but not when engaged. Any ideas/help would be appreciated!

 

[fucawi]

Re: 55 hp Chrysler half throttle? Please Help!

you are not making your problem clear....are you saying the boat only goes half the speed it use to? or half the speed you expect ? or are you saying the engine is only getting up to 2500 rpm?

 

[Seleronn]

Re: 55 hp Chrysler half throttle? Please Help!

I dont really know how to explain it better...

When you open it up all the way, it only goes half speed of what it did previously. The engine only goes what I am assuming to be half throttle, as there is no tach on it.

 

[fucawi]

Re: 55 hp Chrysler half throttle? Please Help!

so it did run good but now it only goes to 1/2 rpm ....check the butterfly is fully open when the control is at WOT.....if it will run at its new max speed for say 1 min without stopping then it does not sound like lack of fuel ie fuel pump....did you do ANY work on it ..like new prop ? Check all linkages carb and ignition advance

 

[fucawi]

Re: 55 hp Chrysler half throttle? Please Help!

There is another post similar to this .the guy found it was bad set of points ..HT voltage ok for low rpm but when cylinder pressure rises not enough HT

 

[Endevor]

Re: 55 hp Chrysler half throttle? Please Help!

Yes I had the same issue. I was only running on one cylinder due to fouled points. Do a plug wire pull test. Pull one wire off crank it if it starts then replace the wire and try the other. If one isn't firing you can say possible issues are points, coil, plug wire or plug is bad.

 

[fucawi]

Re: 55 hp Chrysler half throttle? Please Help!

yes and if you do that with a CD igniton you stand a good chance of bugggering the switch box ..ok with mag or coil ign