Yamaha Engine Flushing Question

[Jameson Clark]

Did the oil changes for my 10 hour service last night and one quick question. After coming from an I/O, I am used to throwing the flusher on the outdrive, going to turn on the water then hopping in the boat and firing it up. From what I read, on the Yamahas, you are supposed to fire the engine before turning on the water. I did not remember this on the first engine (old habits) and had the water turned on for about 20-30 seconds before starting the engine.

So, why is it important to start the engine first and what could/did I mess up by doing this?

Thanks!

 

[fireflymedic]

Water can enter exhaust system and back up to a open exhaust valve and hydrolock your engine.

Same reason you cant drive fast on 1 engine (on a twin engine) or be towed fast without shutting off water cooling lines.

A few seconds doesn't seem to hurt as many people hear have done what you did but not a good practice. If you got water in your engine you would have known it.

 

[NorfolkJames]

I've done it too. I remember it by thinking that it is a water sandwich. Stupid, but it helps me remember.

Engine On---Water On-----Water Off-----Engine Off

 

[Jameson Clark]

That makes perfect since. Thanks for the help!

 

[Jameson Clark]

Couple other things I have to get used to vs my I/O. Not having a temp gauge or oil pressure gauge. I am used to using both of those with my oil changes. Run the motor till it was at operating temp and then on the initial start-up after the oil change, watching when I have oil pressure to verify the oil filter is filled up and I can shut it off and check oil level. Sure do miss having standard gauges!

 

[Scottintexas]

if you haven't seen this yet it's definitely worth watching, it's for the mr1 engine but yours is basically the same, it's by one of our members and is also linked in the FAQ tab at the top of the page, lots of good tips and DIY's in there,

.

 

[swatski]

Couple other things I have to get used to vs my I/O. Not having a temp gauge or oil pressure gauge. I am used to using both of those with my oil changes. Run the motor till it was at operating temp and then on the initial start-up after the oil change, watching when I have oil pressure to verify the oil filter is filled up and I can shut it off and check oil level. Sure do miss having standard gauges!

Yep.
But, you won't miss your winterization schedule, and a couple other things, lol.

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[fireflymedic]

Couple other things I have to get used to vs my I/O. Not having a temp gauge or oil pressure gauge. I am used to using both of those with my oil changes. Run the motor till it was at operating temp and then on the initial start-up after the oil change, watching when I have oil pressure to verify the oil filter is filled up and I can shut it off and check oil level. Sure do miss having standard gauges!

You can tell when the yamaha is at operating temp by seeing a large hard stream shooting straight down to the side of the pump nozzle. It starts coming out when the thermostat opens.

 

[swatski]

You can tell when the yamaha is at operating temp by seeing a large hard stream shooting straight down to the side of the pump nozzle. It starts coming out when the temp regulator opens.

That is true! Excellent point. Also worth noting the temperature of those streams can be (very roughly) estimated by hand, and can be informative.

However, it is important to keep in mind when flushing the engines water pressure (on a hose) may not be high enough to permit water egress/shooting through those "pisser" holes, termostats working or not.
(That will NOT affect the ability to flush/run engines on a hose, as long as there is water coming out of the pumps - there is cooling of the exhausts)

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[captras]

I've done it too. I remember it by thinking that it is a water sandwich. Stupid, but it helps me remember.

Engine On---Water On-----Water Off-----Engine Off

Or easy way for me to remember NEVER have the water on with the engine OFF!