Classic Fifty starting to &$&# me off!

[sportsmanphil]

I have done and checked EVERYTHING!

Running at idle is fine, as soon as I open the throttle, it refuses to climb over 2500 RPM. I hear the carbs open but no increase in RPM.

I had my son at the wheel and I sat back and squeezed the bulb. I would have to squeeze the crap out of it and the engine wanted to take off but would die back to 2500 RPM.

I have completed all E10 updates including proper inlet needles and the revised fuel pump kit.

I completed the 'fuel starvation' TSB. The fuel pump produced over 2.5 inches of mercury (within spec)

I installed a clear fuel hose and found a lot of air right at the fuel pump. I moved the clear hose to the tank and found no air. The fitting at the engine was old so I replaced it. That solved the air. I tested the boat afterward in the water and still not working right.

I come back and gut the carbs (the carbs were rebuilt just 6 months ago) Along with a new gas tank, prime bulb, tune up and link & sinc.

When I gutted the carbs I found a small bit of trash in one of the carb gets.

I am going to hit the water AGAIN in the morning.


Question; Is it possible that some trash in one carb jet to cause the entire engine to refuse to go over 2500 RPM? The rest of the carb was clean as could be. I removed all jets and needles and blew out all passages anyway and found no other debris.

 

[sportsmanphil]

Re: Classic Fifty starting to &$&# me off!

Here is another question that hit me last night.

I replaced the inlet needles with factory ones. When I pulled the carbs apart yesterday one of the needles, the tip turned pink!

 

[CharlieB]

Re: Classic Fifty starting to &$&# me off!

If even one cyl fails under load the motor will not pull up.

Once you are sure that the fuel system is spotlessly clean and the pump is no longer sucking air into the system you really need to use a DVA Meter and check the high speed winding output of your stator.

If the high speed windings are failing to provide enough voltage for a consistantly hot spark the engine RPM will be limited, acting as if a governor is keeping RPM down.

Since there is never any return on electrical parts you must verify any fault prior to ordering any parts.

 

[sportsmanphil]

Re: Classic Fifty starting to &$&# me off!

Well after 2 weeks of screwing with this thing, it fixed. I took it out today and it ran like a raped ape.

E10 gas had caused more issues than I care to reflect on. I found bits and pieces of rubber all in the fuel line, fuel pump and even in the freshly cleaned carbs.

All of the rubber has been replaced with alcohol rated hose. Revised fuel pump, revised inlet needles and the carbs were cleaned out AGAIN along with a new fuel filter. Hopefully this will be the last I have to deal with it.

Anyone have any input why one of the inlet needle's turned pink on the tip? I thought that was kinda odd.