I have a mecury boat engine 25hp and the problem is that my engine will go full speed without choking when the cover is off...but when i put the cover on the engine chokes alot and it wont go full speed..
1. Check to make sure the cowl (or piece of sound proofing) is not covering the front of the carb.<br />2. Make sure the vent slots in the cowl are clear.<br />3. Make sure the cowl isn't grounding (shorting) a plug lead.<br /><br />Chris..........
Also, check for an exhaust leak into the cowl area. This prevents enough O2 from reaching the induction system and may cause exactly what you've described.
I had that problem with a Yamaha motorcycle and it turned out to be a lower crankshaft seal had been damage allowing air to enter. Good luck on finding it.
