20 Most Recent Seloc Mercury Outboard Engine Repair Manuals SEC-1416 1990-00 2.5-275 HP - Page 2 Questions & Answers

water can get into the engine oil from several points if the engine has a sump oil cooler hen the cooler coil wil be cracked or corroded at the seal points more likely the housing behind the water pump has corrosion in it behind the impeller and water pressure is making it leak into the sump

Remove the carburetor and thoroughly clean all of passages by compressed air you probably have blocked passage for fuel on the low idle side

Have to take off gearbox,trm tab must also come off and look for nut inside vavity

check the impellor ! which outboard motor do you have ?

Check your fuel line really good it sounds like you have a pin hole in your line and it's loosing it's prime

check when its on full throttle that the carb butterfly is at 90deg and not over as this will reduce throttle but max advance on ignition !

check compressions 100psi or more on all cyls ! carbs balanced ? sparks on all cyls ? crank seals could be worn ! tick over 1000rpm then in gear 800rpm ish ! In water !

if you mean the water intake on gearbox then the oil seal bellow the impellor housing has failed and needs replacing b4 the gearbox siezes due to water gettin in and not enough oil in it !

make sure its not the gearbox ! drop the box and try the engine again ! ive had this b4 !! when you used it last there was plenty of power and cooling ? easy to strip if it is seized ! please let me know more !

perma gap plug BUWH but also depends what age the motor is ??

low fluid in unit and air in the system raise all the way up put safety lever down remove fill plug and top unit off replace fill plug then cycle up and down 3 complete cycles raise back up check fill level again you may hear air leak out when removing fill plug if low fill again repeat this cycle until unit stays full this should fix the problem if not the pressure relief valve is faulty if there is no external leaks

Your question doesn't make sense,If primer bulb is going flat you have a blockage between primer and tank.also check fuel vent on tank is open

On either side of gearbox

I have a problem with my 2 stroke 20hp mercury 1989,when I run 10-90% throttle it's works fine but when in 100% its only runs in 90% and doesn't sound normal like it's not burning right.

stop switch is on the control box near helm or on the dashboard where you fit your safety lanyard to kill engine wen you fall over ! you also have an ingear safety switch in the control box !

Suggest you clean carb with a good 2 stoke carb cleaner,also check float level,with carb upside down should be parallel to carb body

Sounds like idle jet is blocked,small brass screw on side of carb not one wit spring,screw that one turn in softly then out one and a half turns