Hello friends. I'm told that regular flushing of an outboard used in salt water has a huge impact on the life one can expect to get out of said motor. I recently purchased a very low time used Honda 9.9 outboard. Miraculously, it came with the manual. Said manual stated that the engine could be run in the 1st and 2nd tilt up positions, but not in the 3rd, which is the only one that sees the engine clear of the water in my installation on a Mac 26S. I wondered about how to properly flush the motor since it seems I could not run it tilted out of the water. I called a local Honda Marine dealer, Gulfside Marine Services in Matlacha, FL, who spent quite a long time generously giving me information about this topic and my motor in general. There are a couple of approaches. There is a port in the power head under the cover where you can attach a garden hose with a fitting that comes with the motor. (Which also was miraculously provided with my used motor - previous owner was a bit OCD about keeping track of parts, paperwork, and maintenance, God bless him!) It's a bit of a thing to get this port configured - you need a wrench - and there is risk of loosing either the port plug or said hose fitting in the drink. It does flush and it does get behind the cold/closed thermostat to an extent (there is a small bypass that is always open), but it does not flush as thoroughly as using muffs on the lower unit intakes. It's important to know that this port supplies water after the water pump, so you must not run the motor in this mode or the dry impeller will likely be ruined. So, the better flush is with a regular old muff attachment on the lower unit. The engine runs, gets warm, the thermostat opens and the flush is much better. The tech told me that it's best to flush with the motor running vertically. So, he said to tilt the motor, install the muffs, get the hose running, then tilt the motor back into the water and run it with the muffs down under water and it will work fine. Then after the run, shut it off, tilt it up, and after it's out of the water, shut off the hose and remove the muffs. Then rinse off the lower unit. I've heard elsewhere that you can get corrosion from salt water trapped in the prop hub when you tilt it up. So just to be safe, I plan to rinse out the hub real good to make sure there is no salt water in there. Btw, I noticed that the Honda streams out the pee hole even when it's cold. The old '90 Merc 2-stroke only streamed after the thermostat opened, which could be disconcerting. I also learned that the rubber tube feeding the hole on the Honda is prone to clogging. Anyway, make sure you floss your teeth and flush your motor! If you sail in fresh water, count yourself lucky in this regard!
