Mariner engine flushing

[Jacko]

Goday folks,

I have borrowed my bro's boat for 2 weeks and am not sure how to flush this engine - it is a 2002 Marine 90 4 stroke.

There is no Muffs (like my old unit) so am not sure how to go about it.

There are "threads" at the tell tail outlet which look like they would take an adptor. I have read else where about connecting a hose to certain engines but don't want to take a chance and bugger his engine up.

Any suggestions from you kind folks out there.

Also if that is where you connect a hose are you not flushing against the water pump flow i.e. the wrong direction.

Thank you

Jack

[Richard B]

I don't know the details of that engine, but I have three options with my Yam:
1. Flush muffs (£10 or thereabouts from any chandler) - generic part, use with engine running
2. Adapter - mine doesn't fit to the tell-tale, it's a separare fitting, use with engine stopped.
3. Dunk leg in large barrell, make sure prop doesn't foul the sides and run at tickover (fumes will come up at you )
HTH!

[gavin]

The easiest thing for you to do is run the outboard with the lower end submerged in a clean plastic bin for example, fit a hose in the bin and run it clear for a min or two I think you are safe backfeeding the unit from the telltale, the tap pressure wont harm the pump and it will probably back up very quickly and spill out the telltale

[tue]

You can get muffs for it or the adaptor to go in by the tell tale. If going the adaptor route do not run the engine at all as the water pump will not be lubricated by any water.

[DJL]

Hi Jack,

You are correct about the tell tail outlet.

To flush the engine connect a hose pipe to the tell tail outlet thread. Switch on the tap, but only about half way.
Start the engine and allow it to run for at least 5 minutes. DO NOT run above idle

You have to run the engine otherwise the thermostatically controlled valves that allow water to flow around the power head won't open - hence you also have to run it for 5 mins so the engine gets hot enough for a decent water flow.

Regards
Daniel

*Instructions from mercury/mariner manual.

[gavin]

I would be concerned about the impellor in the pump, if the stat is closed water wont reach the pump housing and the impellor will run dry , this procedure might be okay if the motor is warm but not if the motor is cold, running a water pump without water will destroy the impellor very quickly

[tue]

[QUOTE] Start the engine and allow it to run for at least 5 minutes. DO NOT run above idle

Being a Mariner service engineer I can assure you that if you run the engine with the hose attatched via the tell tale you WILL burn out your impeller and if run for long enough overheat your engine and cause serious damage.

Those instructions sound like the ones for running on a set of muffs.

Also as your back flushing the powerhead the water starts on the "out" side of the water system so the thermostats will not stop water from passing by.

[Jacko]

Jesus,

I taught that was an easy question, but there is oviously two main differances of opion
1 run engine
2 don't run engine

I have downloaded the manual from http://www.marinepower.com/
and saved page 23 as a png below. Hopefully this works.

It seems to indicate that you should run the engine but am confused as TUE says not to and he is a Mariner engineer

what do I do now

[Jacko]

Now heres the text - above too small to read

Jack



After Each Use
1. Flush out the outboard cooling system if operating in salt or polluted water.
(page 17)
2. Wash off all salt deposits and flush out the exhaust outlet of the propeller and gear
case with fresh water if operating in salt water.
Every 100 Hours of Use or Once yearly, Whichever occurs first
1. Lubricate all lubrication points. Lubricate more frequently when used in salt
water. (page 20)
2. Change engine oil and replace the oil filter. The oil should be changed more often
when the engine is operated under adverse conditions such as extended trolling.
(page 21)
3. Replace spark plugs at first 100 hours or first year. After that, inspect spark plugs
every 100 hours or once yearly. Replace spark plugs as needed. (page 19)
4. Inspect thermostat visually for corrosion and broken spring. Make sure
thermostat closes completely at room temperature.*
5. Check engine fuel filter for contaminants. (page 18)
6. Check engine timing setup..
7. Check corrosion control anodes. Check more frequently when used in salt
water. (page 18)
8. Drain and replace gear case lubricant. (page 21)
9. Lubricate splines on the drive shaft..
10. Check power trim fluid. (page 21)
11. Inspect battery. (page 20)
12. Check control cable adjustments. *
13. Inspect timing belt. (page 20)
14. Check tightness of bolts, nuts, and other fasteners.
ohe5
FLUSHING THE COOLING SYSTEM
Flush the internal water passages of the outboard with fresh water after each use
in salt, polluted or muddy water. This will help prevent a buildup of deposits from
clogging the internal water passages.
IMPORTANT: The engine must be run during flushing in order to open the
thermostat and circulate water through the water passages.
Note: You can have the outboard tilted or in the vertical operating position during

flushing.
_______
To avoid possible injury when flushing, remove the propeller. Refer to
Propeller Replacement.
1 Place the outboard in either the operating position (vertical) or in a tilted
position.
2 Remove propeller (refer to Propeller Replacement).
3 Thread a water hose into the rear fitting. Partially open the water tap (1/2
maximum). Do not open the water tap all the way, as this allows a
high-pressure flow of water.
IMPORTANT: Do not run engine above idle when flushing.
4 Shift outboard into neutral. Start the engine and flush the cooling system for at
least 5 minutes. Keep engine speed at idle.
5 Stop the engine. Turn off the water and remove hose. Reinstall the propeller.

[Mosser]

I have the same engine as yourself, but have never used the hose attachment. The muffs work well, and 5-10mins each time does the trick for me.

[Daniel]

I can confirm that Mariner / Mercury are advising people to connect the hose to the special inlet (not quite the same place as the tell-tale) and run the engine.

This inlet is above the inpella and (alegiadly) enough water will back-feed through the system to lubricate said impella.

I think thats a load of bo***ks, and if it was my engine would ignore it all and use muffs or a barrel. My local Merc dealer agrees, far too much potential for damage.

[The Jackeens]

Originally posted by Daniel
This inlet is above the inpella and (alegiadly) enough water will back-feed through the system to lubricate said impella.

I.

Sorry Daniel do you mean above the prop , front or back - the pic he has posted seems to show the hose going into the tell tail port, although its difficult to see.

I must check mine tomorrow

[Daniel]

Next to the telltale is an inlet. It has a small threaded blanking peice of plastic in it and a square head to remove it with a spanner or similar.

[The Jackeens]

Hi Daniel,

just looked at my one outside.

All that I can see is the TT spout sticking out through a circular threaded female connection about 1 1/4 diameter and nothing else near it apart from the breather.

The plot thickens

[Daniel]

What year is your engine?

[The Jackeens]

2003

heres a pic of a 90 mines a 75 but same block

shows breather and TT ports

[Daniel]

I'll look tommorow and post pic of what i'm on about. It could be that i've gone mad.

[The Jackeens]

and zebade says time for bed -- booooonnnnnggggg

paul

[Jacko]

Good evening peeps'

Only a telltail on the 90 as well.
So many different opions on this subject.
Isn't anything in life easy

Jack

[chrisallse]

This is SAD, i have just gone outside and checked mine
mine is the same as yours jackeen. i have flushed mine both from the TT/Inlet and with Muffs, both seem ok and i run the engine. Thats also what the manual states.