Logo

Question for just in time

roscopico

Regular Contributor
"I am pulling my hairs on this

"I am pulling my hairs on this one.

Ok, I get the the Yammy 40 HP 4 stroke out in the water, idle is rough, however I throw quick into drive to gain aceleration. Problem is that it could idle high on with no shutdown. I could put it in drive and it runs no shutdown, when I attempt to increase full speed or more speed it cuts off. (Like it it can't take the pressure)


Thanks"
 
"I think that the fact I am ab

"I think that the fact I am able to cruise at a low speed, means the carb low speed is working. But when I attempt high speed means the high speed cut out. I am able to rev high, and thats ok, because I not under any pressure as if I am moving.

I notice the bulb is not always hard, I need to pump it up. Also noted when I pump the bulb fuel escape in the carb area, leaking but stop.

I want to try this, when I am in the water again, pop the cover, and use my hand, open the carbs to run at MAX. WILL THIS HURT THE ENGINE ? I am thinking about 5 minutes. to clean any crap in the carbs.

Also DO you think there is something going on with my fuel pump, alway have to keep it hard.

Question: Is it the top carb thats responible for high speed?


So far JUSTINTIME, it wasn't running but now its running and starting more easily, we are making progress."
 
"Well Justin time, If my bulb

"Well Justin time, If my bulb is not staying hard, could that be the pump is not sucking to its correct capacity.

Therefore it can't supply enough gas to the top carb, which is responsible for high speed.

I am making any sense
"
 
"I'm the guy with the 225

"I'm the guy with the 225 that started this thread. I have a similar problem, except my Yamaha occasionally stalls while coming up on plane. I can get it going again by pumping the fuel bulb. The boat is in the shop for a new lift pump. Anyway, some obvious things you can check are 1) the fuel/water separator, 2)kinks in the fuel line, 3) air leaks in the fuel lines to the tank, 3) If possible check the fuel pick-up line in the tank for trash and/or switch fuel pick-up tubes if there are two. Beyond that you are probably looking at new fuel pump(s)"
 
u need to run fuel pressure/va

u need to run fuel pressure/vacuum test
if you run off an aux tank and same thing then we know it is on the engine
it could be carbs/filter/pump
 
Back
Top