2005 40hp 2 stroke bogging down under pressure help!

[ahamay1992]

I have a 05 40hp 2 stroke 3 cylinder motor that is bogging down under pressure. on the ear muffs it runs fine it does in neutral and while in drive. but when I put it under pressure it bogs down then when it put it at idle it will shut off. the water pressure coming out of the tube (that is not clogged) is somewhat weak. very weird. I replaced the water pump a couple of days ago still same problem. the carbs have been cleaned out around early December. the thermostat seems to work fine I cleaned out some little rocks that had it held open. very confused on what to do next. if anyone has any clue what I should eliminate it would be very helpful

[TownsendsFJR1300]

I have a 05 40hp 2 stroke 3 cylinder motor that is bogging down under pressure. on the ear muffs it runs fine it does in neutral and while in drive. but when I put it under pressure it bogs down then when it put it at idle it will shut off. the water pressure coming out of the tube (that is not clogged) is somewhat weak. very weird. I replaced the water pump a couple of days ago still same problem. the carbs have been cleaned out around early December. the thermostat seems to work fine I cleaned out some little rocks that had it held open. very confused on what to do next. if anyone has any clue what I should eliminate it would be very helpful

How old is the fuel?

More importantly do you use a good fuel stabilizer and /or literally drain the carb float bowls if sitting for any length of time?

It sounds like your carbs are varnished up again-

Not un-common with ethonol fuel, untreated and it can go bad in as quickly as a month...

I'd at least drain the float bowls now and catch what comes out with a small clean container.


Re the water flow, how did the WP housing look, any heat deformation? Any deformation will affect water flow / pumping..

[99yam40]

good compression, good spark, in spec timing, and timing advancing as it should when it should, and the proper fuel to air mix in the cylinders is needed to create the proper HP under load.

need to test what you can and then look into what you cannot test.

have you looked at the fuel pump?
just because you cleaned the carbs yesterday or months ago, if you get trash in them they will need to be cleaned again

[throrope]

Don't stop at the motor. From expensive lesson, I learned if you don't address everything upstream of the engine including the tank cap, all the work and expense of a carb repair can be undone with a key turn.

[llllumpylll]

Hi
I have had the same problem and it turned out to be a faulty coil. It worked fine but under load acted the same as what you are describing.