Flushing a Yamaha 150HPDi 2-stroke

[blimp]

...anyone know how to do it?

I've had her for a couple of months now, and I really should be doing it after each run out (she lives on a trailer), but I just haven't had the opportunity to take her to the local Yamaha dealer to find out how (40 miles away).

If you know how and can explain, please assume that I'm thick, so try to keep it as simple as you can

[RibinSpain]

Hi, I have a Yamaha 80 & assume all Yamahas have a side direct hose connection for flushing, if not, ignore this post!

There is a side bit of rubber tube just underneath the cowl, about 2 inches long & screwed into a blank cap. The tube is black & about 10 mm diam, there´s only 1, on LHS on mine looking at it from rear.

Anyway, I use muffs & direct hose connector so here goes.

I lower ob down to vertical so all salt water drains out, connect hose from tap to flushing tube using a plastic male fitting I bought at DIY shop (1e or so), turn tap on & give it 2 mins.

You can see fresh water drain out of tell tale & a few other areas. I am usually cleaning boat off while doing this to save time.

Then I attach muffs & fire up ob, idle for 1 min & check egress points.

I do latter as I am not sure yamaha are plumbed for fresh water from direct hose connector touching impellor, so to be sure I only use muffs when firing it up.

I thought it was a real pain going through the above each time I used the boat but having seen the effects of not doing it (ob was shot after 3 years, not mine), I do it each time & once in the routine is easy.

Hope it helps,

[4str]

What he said.

I have a Yamaha 150 HPDI and the built in flusher is on the port side of the engine. It is the small tube that loops from somewhere under the engine out to a connector that unscrews just under the cowling. On mine the tube and connector are grey, the connector attaches to a garden hose once it is unscrewed from the cowling.

Do not run the engine when using this connector! As I recall it says that in the manual, but I don't have it handy at the moment. I use it when I am flushing the engine in a location or at a time when it would be impolite to make noise. Make sure and remember to screw it back on the engine when you are done using it.

A better way to flush the engine is to get a set of muffs that go over the water intakes on the lower unit. Line them up, turn on the water, check that water is coming out of the "pee indicator" on the starboard side of the engine and then start the engine up and let it run at fast idle until you think the thermostat has opened up so fresh water is circulating everywhere.

Most of the time I use a product called "Salt Away" that is supposed to help disolve accumulated salt. It comes as a kit with an aplicator that screws in line with a garden hose. Mechanics here say it keeps the head and water passages free of accumulated salt. Then again, most mechanics work where they sell the stuff - so take that with a grain of salt!

Steve

[4str]

I had troulble logging in and sent the post twice by mistake. Is there a way to totally delete a post?

[jyasaki]

Originally Posted by 4str

Most of the time I use a product called "Salt Away" that is supposed to help disolve accumulated salt. It comes as a kit with an aplicator that screws in line with a garden hose. Mechanics here say it keeps the head and water passages free of accumulated salt. Then again, most mechanics work where they sell the stuff - so take that with a grain of salt!

Sea salt is pretty readily dissolvable in fresh water, so I kind of doubt the Salt-Away is absolutely necessary. It may, however, leave some sort of anti-corrosion coating or residue; don't know about that.

I have run all my motors with just a straight fresh-water flush and have had no problems. That said, there's a lot of folks who leave the boat in the water and almost never flush, and I haven't really heard of too many problems there, either, so go figure.

RibinSpain; sounds like you're going the overkill route: The flush port is designed to flush the motor, and running it on the muffs will flush the motor. Doing both won't hurt, but I don't really see doing both as necessary, either.

Couple of little tips:

If you have more than 2 intakes (the ones on the sides of the legs; Hondas have one in the bottom of the anti-ventilation plate, for example), tape up the one that is not used with a piece of duct tape.

Don't wrap the rpms up while running on the muffs; idle speed or a bit more is fine.

Let the motor run long enough on the muffs to get the thermostats open (should be realtively quick as there is generally less water flow compared to normal running.)

Draining the prop nacelle after recovery and after flushing will eliminate one source of moisture induced corrosion (and in a place where it will not be noticed until you have to disassemble it.)

Luck;

jky