Outboard motor question

[trailertrawlerkismet]

After 35 years of owning inboard boats I find I have questions about outboards…..here is one. Our Yamaha 250 has a fresh water flush hose connection. As instructed I’ve used this to flush the engine upon returning to the dock from salt water trips. With the boat on the trailer can this flushing method be used to run the engine ? Or is a water muff still the correct method for running an outboard motor while out of the water?

Jim F

 

[zekeandboone]

Good morning, Jim!
When I had my 27OB, I was told that the flush out connection was insufficient for cooling the running engine out of the water. I used big muffs, but I was wary of them. I was saving my pennies to buy the Yamaha Flush Bag that the Yamaha reps recommended at the Roche rendezvous, when we traded the 27 in on the 31...

 

[Mike and Sarah]

Jim The hose flush connection can not be used to run the engine on. It does not supply water to the impeller and will damage it and may also cause over heat. If you want to run the engine out of the water muffs is an option and I think yamaha makes a flush bag that you lower the lower unit into. Then fill with water start the engine but make sure to keep the water level high enough. I have used a garbage can to give the same results on a 115 Yamaha .

 

[Submariner]

If I'm rinsing the engine to get the salt out, I use the flushing port and the engine is off. I also run salt-away through the flushing port about every other flush.

When I do maintenance and have the boat out of the water, I like to run the engine to make sure the fuel is primed and everything works before putting the boat back in the water. To do this, I have ear muffs for high HP engines (larger than normal muffs). The F250/F300 has 2 sets of water pickup ports. The muffs will only cover the upper set of water intake. I dry the lower unit and put duct tape across the port and starboard lower water intake. Then turn the water on low to the ear muffs and start the engine. I have a valve on the end of the hose that I use to adjust the amount of water pressure. I adjust that so that I'm getting enough water to come out the exhaust, but not enough to blow off the duct tape.

Here's a picture of my setup using the ear muffs to run the engine.
https://www.letsgochannelsurfing.co...kxdsx4oj-0fad80ac-d26a-4f11-b05d-46959e2e5c5c

 

[knotflying]

Jim,
Channel Surfing is dead on. I duct tape all the screen openings not covered by the muffs. Even with this the water coming from the tell tail is a bit weak. Do not run with the fresh water wash connection. The flush bag is ideal, but way overpriced. You would have to measure to see if this less expensive option will work for you. https://hydrobuilder.com/grow1-collapsible-reservoir.html The 60 gallon may fit.

 

[Submariner]

Incidentally... For the Yamaha F2.5, being so small of an outboard, I couldn't find ear muffs that small which would fit, and it doesn't have a flushing port. So I stick a 5 gallon bucket under it, pour in some salt-away... and idle the F2.5.

I don't run the boat with the F2.5 mounted on the transom rail mount as I doubt it's sturdy enough. But it's a great place to store the F2.5 when at the dock, or anchored. Back at my slip, this is how I flush the small dinghy motor.

https://www.letsgochannelsurfing.com/dinghy?pgid=kxdqbj7e-1b9de171-80a4-41fd-8bd5-cfa75e9fd0da

 

[trailertrawlerkismet]

Thank you all fir your input. It’s good to have the Tugnut members knowledge as a resource for the benefit of us owners.

Jim F