flushing motor

[barney oliver]

will it hurt to idle the engine using the inlet port on the back of the motor. it is a df 200

[Moonlighter]

Yes, it will hurt it! You can only use these flushing ports when the engine is NOT running.

Cheers

ML

[Harper]

You should not run the motor using either the front or rear ports. You can flush with those ports, but only with the engine off (not very effective). Only run the engine using muffs, and ensure that you get the tell tale stream while on the muffs. You should turn the water on high enough that it flows out from under tight-fitting muffs. Flush until the water flowing out at the prop is good and warm (indicating that the engine is warm and thermostat open). The tell tale water will always remain cold, since it is only an indication of a working pump, and does not outflow water that has circulated through the engine.

[Biplanepilot]

What does it hurt in the engine? I have only done this once on my DF140, after a mechanic at my marina said it was ok. Normally I flush with the engine off. Now I am worried.

[Harper]

I doubt that you did any damage. but the owners manual refers to two different ways to flush.....motor running with muffs (and refers to this as the preferred flushing method), or motor off and flushing through one of the upper ports. Mechanics at your marina are not necessarily the best source of advice, unless trained on Suzukis. Supposedly Yamahas are okay to flush through the upper ports with the motor running. But Suzuki doesn't recommend it.

Would you fly your Stearman using a Pitts checklist?

[Harper]

...........and an afterthought.........when you ran the engine with the hose connected at an upper port, did you have water coming out the tell-tale? Not sure that you would have anything out of the tell-tale, and if that's the case, seems to me that even if you have water flowing through the motor while it runs (water pressure provided by the hose itself), you might be running with the pump dry. In which case, even if it doesn't hurt the engine, sure can't be good on the pump. Not sure about all this, just a thought.

[barney oliver]

water was coming out of the tell-tale.

[Biplanepilot]

Would you fly your Stearman using a Pitts checklist?

Haha, good one, and absolutely not

I had read about the flushing procedure when I bought the boat (6 or 7 years ago now) and had religiously flushed it with the motor off, but I had to check something with the boat running out of the water and I don't have a pair of muffs, so I asked the mechanic who supposedly is a suzuki guy, and he said to would be alright.

Anyway, never again. I think I will buy a pair of muffs...seems like they would provide a better flush anyway.

I have noticed that the stream from the pilot water hole has become weaker recently, so I hope I did not cause an impeller problem