Flushing outboards - how often?

[Matteeboy]

Our new boat (with a Merc 60) is kept on a pontoon mooring for the season then will be pulled up in about October. It's in a semi saline river estuary - Just got an engine flushing kit (which I'm struggling to fit properly!) - but it seems the prop needs removing to flush it.

Obviously this is a bit of a hassle so how often does an outboard need freshwater flushing when moored? Wife's grandad has had boats for years and currently has a Boston Whaler with a 90 and only flushes about once a year yet uses it on the sea - Any ideas folks?

Thanks!

 

[longjohnsilver]

Once a year is about the norm. As you have said, possible to do it more often but a pain in the rear.

 

[lovezoo]

And you shouldn't need to remove the prop to flush the engine. The flush muffs (if that is what you have got) fit around the bottom of the leg where the water intake holes are. Have a look at the bottom of the leg and you should see a vertical row of holes on either side. Make sure the muffs cover the holes, turn the water on so that water is coming out of the muffs, then start the engine. Check that water is coming out of the telltale whilst the engine is running.

You should ideally do this after every trip if possible, but obviously this depends on where your nearest tap is.

 

[Its_Only_Money]

Umm every time its used on our rib, via muffs on a hose either at the slip or at home whichever is easiest, no hassle at all when the hose is out rinsing off the salt, why remove the prop???? /forums/images/graemlins/confused.gif

 

[Major Catastrophe]

On a pontoon it is very difficult to flush the engine using muffs.

I have a Suzuki 90 which also has a flushing plug at the top of the leg, which is accessible from inside the boat. I bought the £2 plastic hose attachment to which I attached an 18 inch piece of garden hose and a connector.

I flush my engine after EVERY use, even if I am going to use it the next day. As soon as I am tied up, I remove the plug, screw in the adaptor, snap in the hose and leave it to flush while I attend to all the other things I have to do when I return from an outing. After half-an-hour, I unsnap the hose, unscrew the adaptor and re-fit the plug. Engine is flushed and hose is now available to wash windows, refill water can and then I lock up boat and go.

This is what you need for a Mercury.

 

[Matteeboy]

Prop removal is probably Mercury being a bit too "health and safety" in their manual!
I got a pair of flushing muffs (sorry but I can't write that without sniggering!) but they seem a little large - need squeezing hard to sit on properly. Seems they don't come in many sizes but they don't seem to fit too well despite being the right ones for the engine!
Hose access is good but it's slightly awkward being on a tidal pontoon mooring (for this job - most other times it's very handy!) - Will with have to go down at low tide (goes dry at full LT) or do it with the engine partially raised.

Oh what a learning process this motorboat malarkey is!
Need to get is serviced soon too - Once a year enough?

Thanks helpful people!

 

[Matteeboy]

Major - Not entirely sure if I have that flushing port (I certainly do have the "vents" at near the prop though - Will have a look later. Would be very handy if we did!

 

[fletch17]

I was having problems using muffs. I adjusted them so that the water went in each side, with some hose connectors from B&Q. They work much better now.

 

[SnaxMuppet]

I flush my engine after every use if at all possible.

I have a Suzuki DF115 and these Suzuki engines have a plug at the top of the leg which I remove and then screw in a standard hose attachment from B&Q. I push on the hose and flush through for about 5 mins.

If I cannot do it for some reason (no hose when away, pouring with rain etc) then I try to go back a day or two later to do it.

I have heard that it can extend the engine life considerably. I am not sure if that it actually true but there is little harm in doing it so I might as well especially as the rest of the boat and the outside of the engine also gets rinsed at the same time.

If you have one of these engines and do this just don't forget to take out the adapter and replace the plug... also, don't drop either overboard... that is my constant fear each time I do it /forums/images/graemlins/smile.gif

 

[Major Catastrophe]

[ QUOTE ]
also, don't drop either overboard... that is my constant fear each time I do it

[/ QUOTE ] Same with me. I remove the plug with a surgeon's precision.

Anyway, it seems that the Mercury outboard has an innovative "Freshwater Flushing System", so I would suggest reading the manual or talking to a dealer, but as Arny confirms, with the Suzuki you can flush very easily without fitting muffs.

 

[aquaholic]

Flushing is always a good idea whenever possible, however if like most you are on a mooring and unable to flush then as always its best to run the engine as often as possible if only to keep on top of any salt crystalizing.

 

[Matteeboy]

I love it when I waste money! I'll try and get the "muffs" working when we bring her out of the water - For now, I might see if there's some kind of way of flushing using that "plug" thing.

 

[Its_Only_Money]

My Yamaha has the flushing port too but warns that this only flushes the powerhead so the engine shouldn´t be run while the port is in use (if out of the water you toast the impellor, if in the water you continue to pump seawater around in any case).

Muffs seem a lot simpler! (if you can)

 

[SnaxMuppet]

I am certain that the Suzuki port flushes the head and leg as it takes quite a lot of water before it emerges from the telltail or exhaust but I am not at all sure that it is OK to run the Suzuki while flushing. I certainly don't.

Anyone have any idea if the Suzuki can be run while flushing using the flushing port?

 

[dpb]

If there is water on the pontoon, raise the engine and connect the muffs. lower the engine, switch the water on and run the engine for 5 mins.
Works on out boards and outdrives.
Should be done after every salt water use. But many dont and pay the consequences eventually!

 

[Algey]

Hi
I have a Merc 100hp 4 stroke and flush after every use. I started using a pair of flush muffs as this looked to be more impellor friendly than the flush plug. Which on the Mer screws over the tell tale oulet and forces water down into the discharge of the water pump. After nearly falling in the maina twice whilst fitting the flush muffs I resorted to using the plug method. The manual states the engine has to be run during flushing but not above tick over for 10 mins - to open the thermostat.
After a year of this there has been no perceived reduction in water pump performance, ie the tell tale is as good as ever. /forums/images/graemlins/cool.gif

Cheers
Al.

 

[Major Catastrophe]

Suzuki manual says no to running engine when using a flushing plug, but I flush just after the engine has stopped and the thermostat is open.

I tried the muff method with the engine in the down position, but the tell tale was still pumping diluted seawater after ten minutes.

Matteeboy have you read the manual for your Mercury?????

 

[Haven't-a-Clue]

Major, PLEASE post a photo (if poss) showing the location of the flushing port on the Suzuki, 'cos I can't identify it and would love to flush mine, also how to extract the plug. Ta EVERSO!

 

[Matteeboy]

Major - Of course I have but there's reading a manual and there's real life.
If I stuck to manuals, I'd clean my car headlights and windscreen every time I drove anywhere as well as checking my tyre pressures on each trip too - Not practical!
Manual implies it's best to do it as often as possible.

 

[jfm]

[ QUOTE ]
Anyone have any idea if the Suzuki can be run while flushing using the flushing port?

[/ QUOTE ]

You definitely shouldn't run the engine. When using the flushing port there is no water supply to the raw water pump inlet and the impeller will run dry and will be toast in a few minutes. It needs the water supply to lubricate it. It's a fiddly couple of hours and £50 ish I expect to change a busted impeller , but more importnalty it could let you down at sea with an overheat prob. So dont run the engine!

It is ok to run the engine with muffs becos water is fed to the pump INLET side.

Personally I think the muffs are better than the port. With the port, or any flush-while-engine-stopped scenario, theoretically water can get into a cylinder via open exhaust vlaves. Ok it is virtually impossible with engine vertical, but it is possible if the engine is tilted. Then the engine is a write off next time you fire her up, with hydraulic lock (oldie forumites may remember Dom's hydraulic lock woes). This can't happen if you use muffs and run the engine when flushing. But I appreciate that the flush port is more convenient than muffs so not criticising anyone for using a flush port!