Evinrude 9.9hp decelerate from wot

[pecheux]

Hi guys, trying to help a friend here: he's got a 199? Evinrude (9.9hp) Starts fair ... but once fully trottle is opened (wot) it will only run at that speed for approx 20 seconds or so ... then decelerate to idle ... the dies.
Needs to be restarted with choke ON.

What do I look for in terms of related problem ?

Tx

 

[Xcusme]

Re: Evinrude 9.9hp decelerate from wot

Sounds like either a fuel pump or carb problem (sticky float etc).
Will the motor stay running if you squeeze the fuel line bulb? If yes, look for a faulty fuel pump or air leaks in the fuel lines (tank to motor, fuel pump to carb etc).

This is assuming that you have good cooling water flow and you're not loosing spark.

 

[pecheux]

Re: Evinrude 9.9hp decelerate from wot

Thank you , will check all that ... Now if I take the fuel pump cover off to check the filter ... are there any parts in there besides the filter ? so I dont lose any ... lol

 

[Xcusme]

Re: Evinrude 9.9hp decelerate from wot

Nope, it shouldn't be a problem to remove the thumbnut and inspect the filter screen. Just don't remove the bolts holding the pump body together. That pump cover will have an o-ring to seal it to the pump body. You can check to operation of the pump too. Disconnect the fuel line from the carb, place this line into a can and pull the rope. You should see fuel being pumped into the can. If you see good fuel flow, you'll want to remove and clean the carb, install a carb kit.