Mariner 115hp issues please help

[tommydawg]

ok here is the scenario i bought a 1995 Maxum boat with a 115hp Mariner o/b on it ,,it runs great on the hose but when i put it in the water it will go great for about 3 min then it bogs down if i just let it idle then it will go again then bog down again ,,i took it to a marine service and they have had it now 7 weeks first thing they did was clean the carbs issue still there ,,,then they said it was the trigger assy so they changed that but when taking off the fly wheel a magnet came off so they found me another it came in and it was the wrong fly wheel,,,,,then they ordered another and it came in not only was it wrong again but 1 of the magnets was broken off,,,,so then i found the right fly wheel and it was right and they put it on and it runs better but still bogs down ,,,they tried pumping the ball as it bogs down and no luck,,,they tried spraying the carbs as it bogs down and no luck ,,,,i asked if the stator could be bad and he tells me that the stator just puts voltage back into the battery ,,,,im in NY and we dont get alot of boating here ,,,,,im losing faith in this marine shop i just dont know where to go from here any help would be greatly appreciated thank you tom

 

[racerone]

The stator also provides voltage pulses to run the ignition system. Most shops today are well aware of that fact !!!

 

[Big Rig]

Sounds like the carbs are running out of fuel but then you said that you sprayed them but with what? take a compression check first and if that is all ok then check for a vaccum leak. still sounds like a fuel delivery problem cause when you leave it idle the carbs fill up again and it will go. take the hose off the intake end of the primer bulb and blow back into the tank to dislodge any thing that may be in the tank over the end of the pickup tube and try again. If there is something in the tank then that is why it soesn't do any good to pump the bulb.

 

[Jerry Young]

Be careful running. You could be running at idle on the fuel being supplied to the cylinders and not have a problem, then as you increase throttle you may not be getting enough fuel to each cylinder which also means that the cylinder is not getting the lube needed. This could lead to a piston starting to seize up causing you to get the bog down feeling. Make certain that each carb is correctly adjusted.

 

[pigeon laker]

Check the exhaust divider plate gasket.My Merc 115 ran like crap for 3 years.No one could figure it out.I found the solution on this forum.Water from the exhaust was leaking into the cylinders.The plugs were pretty clean though.