Starting advice

[Blakeys7]

I have a mariner 75hp two stroke.

Having only run it a couple of occasions, what is the best practice for starting as I managed to flood it the other day. The key has the push to choke function, so I primed the fuel and turned it over. I repeated a few times and in the end I got it going by opening the throttle and then turning it over until it started with a nice puff of smoke 😁

Thanks for any advice

[Xk59D]

Had one years ago and first start of the day was always a faff. With older 2 strokes there is generally a knack each one likes to start easier so may take some finding out and experimenting on your part.

I always ran my carb engines dry so I held choke on with full idle bar set when cold until it coughed and at that point you had to play with choke to keep it running for a few seconds until all carbs had fuel.

[spartacus]

If it's anything like my old school Tohatsu, here's how I do it.

1/ Open vent on fuel tank and prime fuel bulb until it goes hard
2/ Ensure killcord is attached, open fast idle lever all the way
3/ Key in ignition, press choke for a good 20 seconds
4/ Turn engine over (short burst) as you can burn out the starter motor otherwise
5/ Once engine catches, use fast idle to control

Ensure spark plugs aren't fouled. If it hasn't been used for a while, pull them one by one, remove any carbon build up with a soft brass bristle brush and dry. Don't over-torque if the thread on the plugs are lightly greased.

On my engine, once it's warm, it starts on the button without choke or fuel priming.

I always run the engine dry of fuel after fresh water flushing, which avoids stale fuel sitting in the fuel bowls on the carbs. Disconnect fuel hose, lightly rev until it dies.

[whiskylee]

Try holding in the key to activate the choke and wait 10-20seconds before turning over, you could give 1/4 throttle as well. I do this on my 2 stroke V6 mercury [emoji106]

[paintman]

Originally Posted by whiskylee

Try holding in the key to activate the choke and wait 10-20seconds before turning over, you could give 1/4 throttle as well. I do this on my 2 stroke V6 mercury [emoji106]

Yep, much the same - mine's the Black Max V6.
Pump the primer bulb till it's hard, open throttle lever slightly, hold the key in to activate the choke, mentally count slowly to 10 whilst still holding the key in & then turn the key to start.
USUALLY starts first go.
Wait for harbour to reappear as the cloud of smoke dissipates

Usually starts without any faff for the rest of the day - although just opening the throttle a tad helps.

[Last Tango]

Originally Posted by whiskylee

Try holding in the key to activate the choke and wait 10-20seconds before turning over, you could give 1/4 throttle as well. I do this on my 2 stroke V6 mercury [emoji106]

And on a carburated engine, what do you suppose is happening while you wait 10-20secs. (other that the choke solenoid is draining power from the battery).

[paintman]

'Choke' is a misnomer, Mercury/Mariner refer to it as an 'enrichment valve' but then go on to use the word 'choke' in their instructions.

"The enrichener system provides the engine with a rich fuel charge for starting ease of cold engine. The system consists of an electrically operated enrichener valve which is connected by hoses to the carburettors.
Fuel is gravity fed to the valve from the float bowl of the top carburettor via a hose. When the key (or choke button) is pushed in (and held in) current is sent to the valve causing it to open, which allows fuel to pass thru. The fuel passes thru a hose and is supplied to the engine via fittings located on top of the middle and bottom carburettors. When the key (or choke button) is released the valve will return to the closed position."
Source: Mercury/Mariner Service manual 90-97658-3 Models V-135 thru V-225.

It then goes on to caution against using when engine warm to prevent flooding.

ETA. A quick google 'Mariner 75 2-stroke enrichment valve' would suggest that it's also got one.

[Last Tango]

Makes sense

I found with my 75 Merc fast idle & spin it for a couple of seconds then push the "choke" for a second while it was spinning. First time, every time.

Only used the choke once at the start of the day.

[Blakeys7]

Some good advice from everyone. Makes each of our OB's unique. Hopefully I will find my own engine's ideal best starting practice and with any luck before im holding up the slipway

[Wightdiver]

Originally Posted by Blakeys7

Some good advice from everyone. Makes each of our OB's unique. Hopefully I will find my own engine's ideal best starting practice and with any luck before im holding up the slipway

If all else fails, a squirt of easy start!!

[whiskylee]

Originally Posted by Last Tango

And on a carburated engine, what do you suppose is happening while you wait 10-20secs. (other that the choke solenoid is draining power from the battery).

Paintman describes the process [emoji106]

[uncle al]

Please don't use easy start, if you do, your OBM will get addicted to the damn stuff. I have rebuilt goodness knows how many engines because of that sort of stuff. But at the end of the day I am an old fashioned motor mechanic.

[jeffstevens763@g]

Originally Posted by uncle al

Please don't use easy start, if you do, your OBM will get addicted to the damn stuff. I have rebuilt goodness knows how many engines because of that sort of stuff. But at the end of the day I am an old fashioned motor mechanic.

+1 once you use it, starting gets worse not been involved with it for years used more for site engines never on my own.

[Xk59D]

Can someone please tell me how an engine gets "used" to easystart..I'm genuinely curious, are outboards smart enough to know to mess with timing or mixture when dealing with carb engine when you fire a shot of easystart at it so next time it won't start without it?

Surely if you need to use easystart something is wrong so it will eventually get worse you would assume, which perhaps is where engines get "used" to easystart came from?

Btw I'm not advocating using it, if engine won't start probably worth looking for the source.

[breezeblock]

Originally Posted by Xk59D

Can someone please tell me how an engine gets "used" to easystart..I'm genuinely curious, are outboards smart enough to know to mess with timing or mixture when dealing with carb engine when you fire a shot of easystart at it so next time it won't start without it?

Surely if you need to use easystart something is wrong so it will eventually get worse you would assume, which perhaps is where engines get "used" to easystart came from?

Btw I'm not advocating using it, if engine won't start probably worth looking for the source.

common myth generally speaking if an engine needs aerostart it doesn't have enough compression to get the heat in the cylinder so its probably worn to start with or if its petrol theres usually a fuel issue or some other issue but on the other hand the dum-trucks that we do come factory fitted with a aerostart and will run 30000 hrs without serious work done on them

[beamishken]

Originally Posted by breezeblock

common myth generally speaking if an engine needs aerostart it doesn't have enough compression to get the heat in the cylinder so its probably worn to start with or if its petrol theres usually a fuel issue or some other issue but on the other hand the dum-trucks that we do come factory fitted with a aerostart and will run 30000 hrs without serious work done on them

Exactly right urban myth formed from people who use it to start knackered engines that wouldnt start otherwise

[jambo]

Well knowing the guy and his experience I’ll as always follow what Uncle Al says!

[breezeblock]

lets think about this logically its an engine it can't think for itself if its petrol it needs fuel and a spark to make it work if its diesel it needs the heat from compression to ignite the air/ fuel mix its as simple as that I use either aero start or brake cleaner quite regular for fault finding on both types and once you've fixed the problem that it had to start with there is no problems the theory of addictive engines is about as delusional as religion

[beamishken]

Originally Posted by jambo

Well knowing the guy and his experience I’ll as always follow what Uncle Al says!

If he can offer a reasonable technical explanation as to why an engine gets addicted to it id love to hear it
I've never used it in 30 years of building engines but there is no reason why using it on a healthy engine for the odd diagnosis fire up should do lasting harm

[breezeblock]

Originally Posted by beamishken

If he can offer a reasonable technical explanation as to why an engine gets addicted to it id love to hear it
I've never used it in 30 years of building engines but there is no reason why using it on a healthy engine for the odd diagnosis fire up should do lasting harm

exactly