Best method for flushing outboards

[Y-Not]

I have a 2003 model 90 hp 2stroke mercury.
I have been flushing it up till now using the built in hose connector to purge the system of salt & water. Run it at idle for a few minutes then just let the fresh go through for about another ten. easy stuff.
Was talking with another boaty about this over easter and he said that these inbuilt flushes dont work that well to clean the water pump area and the use of muffs is really the only way to go if you want the motor to last.
I obviously do want the motor to last the owners manula doesnt suggest the use of muffs that I can see (I have been previously accused of being blind ) and the water inlets appear to be in such a place that I dont trust that a set of muffs would stay in position to run it unattended while I clean the catch etc 8).
What does every one think. Should I continue with the flush system or invest in a set of muffs??? ??? ???

[Oldyella]

Muffs will do no harm and are cheap... But you need to replace the W/P impeller every 2nd season, so a bit of salt in there won't hurt as long as the purge flush cleans the water passages in the motor.

[basserman]

muff all the way unless you have a big drum then that would be the best of all
however most of us don't have a big drum the room or water for on so the muffs are the better way
and by the way that person was right the hose conector does very little apart from keeping the nagbours happy

[deb]

Wondered the same thing,when our boat changed to a 90. Went to produce store and got a empty poly 40gall drum. It has a tap on the bottom of it, just cut the top off. Hose doesn't take long to fill it, turn the tap to empty it (or put hose in it for the garden).
At least the leg goes all the way in, just like its in the water.

[Cheech]

Y-Not,,, I am so jealouse. I had a motor on my previous boat that had the hose connection flush and I never used muffs. Had lots and lots of discusions about the pro's and con's.

My mechanic said there is no reason they would not flush everything as the thermostat is never fully closed anyway (by memory he said that), and you are bumping the water backwards so has to flush the motor.

At the end of the day, the manufacturer would not say to use it if it was not suitable.

I change my impella every annual service.

Be a bit careful of what answers you get here as I have noticed with this subject you will get a lot of flusher people saying muffs, because "back in my day,,, there were no fang dangle plug in things.. Gotta use muffs".

Gee, I think I just got half off ausfish offside.

Unfortunately with my current motor it is muffs.

Cheech

[youngfisho]

The old man owns a 60 hp yamaha 4st, which has the plug hose fitting. He has racked up nearly 200 hours on his boat and there was no adverse damage to the impeller when it was time to be changed. The water would not only pour out the tell tale but also where the water pick up down near the leg. Ensuring that you flush the motor asap and dont let the salt water dry up. Will help to minimise corrosion and salt build up.

There are some products on the market that inhibit salt build up that you flush through the motor. Salt X and MACS. Was in Bush n Beach magazine october 04 issue. Can find these at local marine shop.

andrew

[finga64]

If you use the snap on connection for the flush and if the water didn't get down and flush out the pump etc wouldn't the impellor melt?? ???

[Spaniard_King]

finga,

when you use the flush attachment (not muffs) you don't run the engine.

At my work we have Honda engines all doing about 700-800hrs a year never flushed an engine yet(we have several engine with over 1700hrs on them), we pulled a 225 down a couple of weeks ago to change the engine mounts and there was not a skerrick of corrosion in the water passages. Just incase you are wondering changing top engine mounts on a Honda requires the gearbox, leg , engine sump and the powerhead to come off.

regards

Garry

[finga64]

aah, that clears a lot of ideas!! thanks, my old brain is a bit slow sometimes.

[Spaniard_King]

Forgot to mention, I still flush my own outboard using muffs

Garry

[cooky]

i was told the merc flush attach is not to be used when running motor as it only flushes the head.

This was last week by a very experienced marine mechanic (and merc dealer).