Evinrudes 35hp Elan

[Roi King]

Hi, I have a 35hp 3 cylinder Elan that will not run on full throttle, it starts and runs ok up to about 3/4 throttle after that it starts to judder but does not stall. I have replaced the spark plugs and the fuel filter is clear?

 

[joereeves]

Explain/describe "judder". That's a new one to me.... and I've been around awhile.

 

[Roi King]

Hi, sorry i should have given more info, by judder i mean it begins to run unstable and loses power when i throttle back it picks up, could it be the carbs want balancing. Roi

 

[haffiman37]

Sounds like a fuel capacity problem. Might be the pumps, there are two, might be an air leak in the connector hose. Try squeezing the primer bulb when it happens. Do you still have the original oil-mix system on the engine?? That system is known to cause a lot of problem and is better removed. Mix 2% in the fuel and leave only the main fuel pumps.

 

[Roi King]

I have tried squeezing the bulb when having the problem but it makes no difference to the running, the original oil-mix system has been removed and i now mix it myself.

 

[racerone]

drain the gear oil---------- Look for water and metal bits.