WHOSNEXT

Just picked up a boat, and was wondering what does this flush out?[ATTACH=CONFIG]546085[/ATTACH]

Too Stroked

Generally speaking, that's usually a fresh water flush for the engine. Without seeing the plumbing attached to it though, I can't be 100% sure.

WHOSNEXT

Motor is a 496mag so I believe it does not flush motor.

PARASAIL941

It flushes out the raw water side of cooling system. Only the block and heads are cooled by the "closed cooling" system , exhaust and coolers ( oil , p/s , fuel.) are cooled by raw water. Good Luck!!!

Smitty

Fresh water flush point. Make sure that cap is always on tight.

Sydwayz

What others have said above...

Your engine still has sea/lake water flowing through it:
sea water pump
heat exchanger
fuel cooler
exhaust

You must flush it out just like any other motor sans a closed cooling system after salt or brackish water boating.
You just don't have to do it as long or wait for it to warm up, as their is no thermostat in the sea water side of the system.

1) You must run the motor for it to flush. It's not a pressurized wash down system.
2) Turn on the hose, and let it run for about 2 minutes, to backflush out the drive.
3) Flush the engine for about 5-7 minutes or so.
4) Turn off the motor, and let it backflush out the drive again for 2 minutes.

Always make sure it's tightly closed, and do yourself a favor: go buy a solid brass quick disconnect from your favorite home improvement store. It's a lot easier to thread on the quick connect when it's time to flush, than it is to thread on a hose. Then you just pop the hose onto the quick connect. Keep them in the boat.

WHOSNEXT

So I can use this to flush out raw water instead of muffs?

can i blow out system from here and add antifreeze to winterize ?


[QUOTE=Sydwayz;4362359]What others have said above...

Your engine still has sea/lake water flowing through it:
sea water pump
heat exchanger
fuel cooler
exhaust

You must flush it out just like any other motor sans a closed cooling system after salt or brackish water boating.
You just don't have to do it as long or wait for it to warm up, as their is no thermostat in the sea water side of the system.

1) You must run the motor for it to flush. It's not a pressurized wash down system.
2) Turn on the hose, and let it run for about 2 minutes, to backflush out the drive.
3) Flush the engine for about 5

Sydwayz

Yes, you can do you antifreeze from there. But you can't blow anything out with air pressure. The system is not designed to take any kind of pressure like air would introduce from a compressor. Your impeller blocks anything from going upstream that you would introduce there without the engine running.

Also, you have the air drainage system. See if you can obtain a 496 Mag manual. It's very informative.

stimleck

Since we are on the subject would flushing an open cooled system this way count as back flushing or is that a different process?

Sydwayz

No.

"Back flushing" is basically removing the outlet from the Sea Water Pump, and pulling hoses off the top of the motor to backwards flush through the motor. Typically you would do this when you have pieces of impeller 'missing' in the engine, or coolers. Often, you need to back flush each component of the cooling system. This might also be needed when you have plugged a motor full of sand or mud. Pulling all of the drain plugs during this process is also normally done.

Typically, those flush fittings as indicated in the first picture introduce the fresh water (from the hose) directly before the Sea Water Pump. The veins of the pump prevent it from going any further 'forward' into the motor/coolers, etc. The only thing that it "back" flushes would be from the sea water pump backwards through the drive. This is also VERY important to do so you don't get salt water build up and associated corrosion blocking off these water passages.


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The advantages of having a fresh water flush fitting installed are basically threefold:
1) You don't have to mess with muffs on an outdrive, which is particularly cumbersome if not impossible if you have a Dual Water Pickup drive.
2) You don't have to count on the Sea Water Pump/Impeller to draw water all the way up to itself. The hose inlet is typically plumbed directly infront of the SWP. (This makes it about 100,000,000 times easier to winterize with antifreeze.)
3) If you were so inclined, you could put ball/valve fittings into the system and flush a boat out with fresh water while it's moored in salt water. BUT, you MUST remember to open the ball valves before you go boating again. Many folks have burned up pumps and motors because they have not done so.