Engine flushing 150 yamaha

Freddie Can

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Joined
Jan 20, 2022
Messages
8
Engine not flushing thru "Pee hole". bought new Yamaha 2017 150hp. Have a dock with a lift and boating in salt water. 1.75 years later realize water hasn't come out of pee hole when flushing. As per a neighboring marina's techs I performed a few things incase line plugged. In end they said bring over to one of their docks and see if it will flush, which I did and it flushed which I assume means problem isn't the engine.
I checked water pressure at marina's docks....45psi. I checked at my dock....30psi. Again it flushes at marina dock(45 but not mine(30). I am member of a Boating Association as part of Condo Association. All of this was known 15 months ago, to this point Boating a
Association has balked at upgrade of waterlines. I haven't used my boat in 15 months as afraid lines will plug and blow engine.
1. What water psi is recommended with garden hose flush?
2. In lift, lower unit is flushing, but nothing out of pee hole which I believe, and have been told, means the upper part of engine is not getting flushed while lower unit is
3. What water psi required for mufflers?
4. Do you run engine with mufflers on? Or will it flush lower unit and engine without engine running?
5. Can my 2017 Yamaha 150hp be flushed with mufflers?
6. Since I probably ran up 90 hours without it flushing thru pee hole is there a chance cooling lines could be narrowing with salt build up? Which may require higher psi to flush?
7. Is it too late for "Salt Away" flush to clear lines if salt building up? For this to work does engine have to be out of water? Or do I need it in a lift?
8. Am considering mufflers to flush? Are they dependable and flush on my 150?
9. I will need to have a marine dock co. add a step of some sort on to my lift so I can step around to get mufflers on. Anyone do this? Cost?
10. In considering mufflers, any specific brand recommended to purchase
11. Anything else I haven't questioned that you think I need to know?
Look forward to replies................Freddie Can
 
Last edited:

99yam40

Fleet Admiral
Joined
Sep 7, 2008
Messages
9,097
just to let you know a muffler is something on a motor to quiet the exhaust out of a motor.
muffs are for flushing an outboard that you attach to a lower unit on the water intake area.
maybe Brits and Canada people call them mufflers for some reason.

I am not sure if you are running the motor while using the hose attached to the flush connector or not, but your manual should tell you that that is not a good idea.
and without running the motor the stat will not be open, so no water flow thru the heads to rinse that area.

probably best to do muffs and the flush port at the same time while running the motor
 
Last edited:

Sea Rider

Supreme Mariner
Joined
Sep 20, 2008
Messages
12,345
Does the motor counts with a dedicated flushing port located at upper midde leg ? If so, does it needs a flusher adapter or can hook a garden hose right there ? Flushing thru a flushing port is much better than with muffs, there's 0 water spills along pressure loss as seen when on muffs.

Is the peeing port pees as if having prostate issues, poke in out severeal times the plastic red cannula, the ones delivered with canned aerosols such as WD-40, Carb Cleaners, etc with motor ON, if the port is somewhat salt clogged that procedure should take care of it.

Does the peeing port have an attached rubber hose that connects to the lower block ? if so, remove it and poke same cannula in/out thru the internal port with motor OFF. Can spray some shots of WD-40 in both described situations to help dissolve salt deposits.

Nope,Salt Away won't do a thing if the motor has already collected heavy salt layers, crusts in the entire water passages, it's intended for new motors out of the box flushed periodically to work as promoted...

Happy Boating
 

Freddie Can

Cadet
Joined
Jan 20, 2022
Messages
8
just to let you know a muffler is something on a motor to quiet the exhaust out of a motor.
muffs are for flushing an outboard that you attach to a lower unit on the water intake area.
maybe Brits and Canada people call them mufflers for some reason.

I am not sure if you are running the motor while using the hose attached to the flush connector or not, but your manual should tell you that that is not a good idea.
and without running the motor the stat will not be open, so no water flow thru the heads to rinse that area.

probably best to do muffs and the flush port at the same time while running the motor
sorry, know it is muffs. not running engine to flush
 

Freddie Can

Cadet
Joined
Jan 20, 2022
Messages
8
just to let you know a muffler is something on a motor to quiet the exhaust out of a motor.
muffs are for flushing an outboard that you attach to a lower unit on the water intake area.
maybe Brits and Canada people call them mufflers for some reason.

I am not sure if you are running the motor while using the hose attached to the flush connector or not, but your manual should tell you that that is not a good idea.
and without running the motor the stat will not be open, so no water flow thru the heads to rinse that area.

probably best to do muffs and the flush port at the same time while running the motor
How much PSI needed to use muffs to flush upper engine and lower unit
 

Freddie Can

Cadet
Joined
Jan 20, 2022
Messages
8
Does the motor counts with a dedicated flushing port located at upper midde leg ? If so, does it needs a flusher adapter or can hook a garden hose right there ? Flushing thru a flushing port is much better than with muffs, there's 0 water spills along pressure loss as seen when on muffs.

Is the peeing port pees as if having prostate issues, poke in out severeal times the plastic red cannula, the ones delivered with canned aerosols such as WD-40, Carb Cleaners, etc with motor ON, if the port is somewhat salt clogged that procedure should take care of it.

Does the peeing port have an attached rubber hose that connects to the lower block ? if so, remove it and poke same cannula in/out thru the internal port with motor OFF. Can spray some shots of WD-40 in both described situations to help dissolve salt deposits.

Nope,Salt Away won't do a thing if the motor has already collected heavy salt layers, crusts in the entire water passages, it's intended for new motors out of the box flushed periodically to work as promoted...

Happy Boating
how much water PSI to have muffs flush engine?
 

conrad503

Cadet
Joined
Jul 4, 2021
Messages
18
If you're flushing with muffs, but not running the engine, seems like you're gonna need A LOT of psi because the impeller of the water pump isn't turning. Consequently you'll need to pressurize the crap outta the pump to physically move the rubber impeller blades enough to allow water to pass by them. And really I can't imagine how it will work at all, since the muffs will leak long before the impeller blades give way. Maybe I'm wrong, happy to be educated by someone that knows better than I.
 

Sea Rider

Supreme Mariner
Joined
Sep 20, 2008
Messages
12,345
Does the Ownwer's Manual states that such motor needs to be flushed with muffs while motor is OFF ? If so the thermo wil never open and the cylinder head area won't never be flushed cleaned.. Should work OK if flushing with motor OFF through the dedicated upper flushing port provided the water pressure is enough to open up the t-stat. The requested info should be stated in the Owner's Manual, a matter to check it up....

Happy Boating

 
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