small engine stalling when not tilted

[oceanjunkie]

I'm new to the board. I recently got a new 8hp 2 stroke yamaha. I have it running at 25:1 oil mixture for the break in period. Sorry for the long description, but hopefully it will help diagnose the problem:<br /><br />It was a pain to get started at first. Once started it ran at low speeds ok. I tried to give it some more throttle and it stalled as it sped up. This happened a number of times as I tried to figure out the problem. Each time it was still hard to restart. I checked the fuel lines and they seemed ok. Today I realized something odd when I was flushing it on the trailer. I had the gas line disconnected and the engine in the trailering position and it ran great (so I guess the fuel lines are not the problem). While it was running I put it down to the low trim setting and it stalled and wouldn't start back up. I put it back to the trimmed up position and it started no problem. I did this a number of times with the same results. Sometimes I would need to pull the choke out to get it running again in the trimmed up position. So I think when I gave it gas while on the water, the engine's powerhead was leveling off as I was planing off and this caused the engine to stall just like on my trailer. <br /><br />What would cause the engine to stall when it wasn't in the trimmed up position? Any help would be greatly appreciated.<br /><br />Thanks in advance<br />-Jeff

 

[Havoc]

Re: small engine stalling when not tilted

It sounds like a fuel issue.<br />Could it be the float position in the carbs? Thats the only thing I would think could change the way it runs in a different position. <br /><br />Maybe you dont have the floats set high enough and the fuel level in the bowl is to low for it to climb onto the main jet.<br /><br />If its a new motor I would think it is something the dealer should look at under warranty.

 

[Knightgang]

Re: small engine stalling when not tilted

I gotta agree with Havoc that it sounds like carb float adjustment. THe dealer should take care of it under warranty if it is new. Let us know what it was.<br /><br />Knightgang

 

[oceanjunkie]

Re: small engine stalling when not tilted

Thanks for your help and sorry for my delayed reply. One thing that I suspected but didnt mention in my post was that the gas was stale. I didnt think it would cause the engine to have the problems I described, so I didnt even consider it. I filled it with new gas and sure enough the engine starts on the first pull now and runs like a champ. Maybe the float valve is more/less buoyant in stale gas than in good gas, so thats why the engine was stalling at different trim settings like you guys suggested. Anyway, thanks again for the help.<br />-Jeff