The wife has a 90's Merc 3.3 long shaft for her wee yacht and since we've had the engine it's telltail has always just dripped. I've just replaced the impeller on a std service and it's pumping like a good 'un.
The engine hasn't had a lot of use but it will be soon so I want to ensure that water flow to the engine is ok.
Is it a case of pushing hot water thru the system to try clean out any salt deposits?
Any guidance welcome.
Live your life as if it was a revolution - don't just evolve!
Try pushing a bit of strimmer wire up the telltale as far as it'll go, the tell tale might be part blocked.
Originally Posted by delitubby
I've just replaced the impeller on a std service and it's pumping like a good 'un.
Wakey wakey Nos! (Good advice tho'.)
The fact your new impeller is pushing a lot of water through the engine is 90% of the battle. What may be going on inside is that salt has literally caked & baked onto the surfaces. Even warm water isn't going to shift that in a hurry, and the other problem you might have is by "cooling" with hot water you do more harm than good.
If there is a quantity of water coming out the exhaust port at the bottom of the leg it's probably OK.
I have just services a Yamaha 2HP and since I owned it the waterflow out of the leg has never been more than a slight spray.
I recently stripped the head from the leg and found loads of salt deposits in the various channels that route the water to the head and then also in the head. I used a piece of wire to loosen everything up and then flushed with hot water. It took a few goes however now the water flows out much more easily.
If your engine is same as posted pics, it's a rebadged Tohatsu. The best way to solve this problem, is to remove right side cover, pull water tube from engine, will see a small peeing tube. Get a thick needle, thick fishing line, W40 or carb cleaner plastic cannula and insert back & forth several times. Usually cloggs internally and very rare on water indicator exit.
That engine has a water flushing port under engine lower body, check red line in second pic, unscrew nut, buy a water flusher if possible and connect it there, conect hose to house water pipe, pressure will pop-out any obstruction, whether salt , debris, whatever. Flush with engine off.
Flushing from time to time will maintain all water paths in inpeccable condition. On those engines will see poorly peeing or hesitation at idle speeds, will pee near a teenager when giving more juice to engine, providing small crankcase tube is completely unobstructed.