Mariner 4 2 stroke. Do they not like being transported on their side?

ProDave

ProDave

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Launch day today, and like last time, the motor let me down. A 2003 Mariner 4 2 stroke outboard.

2 days ago, I ran the motor at home in a tank of water. It started first time, I ran it for a while to warm it up, and ran it in gear (only at low revs otherwise it empties the tank!) The motor had been stored upright in the garage over winter.

So I launch the boat, and the motor won't start. Had to walk the boat from the slipway to the harbour again.

2 hours later when everything was set up, the motor started and seemed to run okay.

As I say, we had the same problem last year. That time I bought the motor home and found gunk in the fuel filter bowl which I blamed, but now I'm thinking that was a red herring.

The common theme is both times it has failed to start it has been on it's side for about an hour. I'm beginning to think this motor does not like that.

Both times, it would start, but barely idle, and die as soon as you put it in gear. Sounding like fuel starvation?

Anyone else experienced this problem, and is there a solution such as perhaps turn off fuel and run the carburetter dry before transporting for instance?

Otherwise I'm tempted to fit a wooden block to the trailers winch post to transport the motor upright.
 
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Our local outboard guy told me that the didn't like being transported laid down. Something to do with fuel going into the wrong places I think. It was some years ago so I cannot recall the details. But we had a starting problem a couple of times.

We now transport upright with the fuel turned off and the problem has not recurred.
 
Thanks for the response, so I'm not the only one then.

The fuel was turned off, so I can only think the problem was fuel already in the carb getting somewhere it shouldn't, which is why I wondered if turning off the fuel and running the carb dry before tansporting might be wise?
 
I would always say to turn the fuel off & let the carb run dry before transporting or storing - if only to avoid spilt petrol. You'll also save yourself a load of grief in the long run with bunged up carbs.

I don't think it's causing your problem, though.

Are you setting the idle speed in the tank at home?

If you are, I suspect that you are setting it too low. i.e. it will be correct in the tank, but not high enough to counteract the exhaust back pressure when the motor is fully immersed when it's on the boat.

If it will start and run, try tweaking up the idle speed adjustment until it runs correctly. Also, give it a few moments to warm up & make sure it revs freely in neutral before engaging the gears.

My 0.02p

Andy
 
May be there is a possibility that fuel remaining in the carb could find its way into the crankcase and cylinder and soak the plug if transported the "wrong way" .

I have never seen any mention of it anywhere though and carrying my Evinrude by the carrying handle would definitely be the "wrong way"!

The usual way to lay an outboard down is on the side of the tiller. Laying on the gear shift lever, if thats on the side, can break them off.

Blasted difficult to transport a long shaft outboard up right in a small hatch back! (not easy even lying down!)
 
The problem is not caused by the engine laying on its' side.

I have the 5hp version which is very near identical, and before that the 4hp Yamaha which is also near the same; they are transported in car boots, and more to the point my boat locker, on their sides ( lying on the tiller, incidentally ) and have no trouble.

You do have to be very careful about this with 4-strokes, but the 2-stroke is fairly bullet proof.

They can have trouble with the electronic ignition module, or you could have a fuel supply problem.

I'd also query where you buy your outboard petrol, if a small marine outlet it may not get the throughput or maintenance to steel tanks desirable; certainly worth thinking about the old chamoise leather in the funnel filtering trick, however you do it check for particles of rust or dirt in the fuel, water too.
 
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Intermittent fuel starvation

It's worth checking that the fuel filter in the tank is doing its stuff. I have had one break off the top of the tap fitting, with obvious consequences.
 
Same engine, similar problem

I've got the same engine. It is usually very reliable - starts first or second pull. If it hasn't been used for a while, it sometimes won't even try, or may only run with some choke. I've now got stripping the carb down and clearing the jet off to a tee (10 mins max). if it doesn't start in 4 or 5 pulls - carb strip time.

You must allow the motor to run out of fuel before storage (ie turn the petrol off & wait for the engine to stop) - or drain the carb (there is a hole in the case that allows a screwdriver to loosen the drain plug in the carb bowl). The jet blocks with dried 2 stroke oil - petrol evaporates away and leaves enough thick stuff behind to block the jet.

Even though I know what to do, last weekend we packed the boat up before realising we hadn't run her out, and I can't get access to the drain plug without taking the engine off the boat, so next time I'll probably have to take the carb off & blow through the jet again.

Mine is always "stored" upright on the transom of the boat.

My brother took some video last time, which I may be able to make available if required.
 
My wee Mariner goes back and forward, lying on its side in the car, without any problems. As others have said it's best to run the carburetter dry.
 
maxcampbell said:
You must allow the motor to run out of fuel before storage (ie turn the petrol off & wait for the engine to stop)
Click to expand...

I always thought this was a bad idea on 2 strokes, running dry of fuel = running with no lubricant...

I go for stopping the motor by pulling out the choke (then press button if it doesnt stop right away) if storing for a long while, then drain the fuel when back in the garage.
 
six of one-half a dozen of the other.
2 strokes have roller bearings which will retain a film of oil. The piston rings are the other friction surface and so long as you run out of fuel at tickover and not after a full throttle blast they should be OK The motor will only stop when there is no fuel, and therefore oil, left. So whilst it is running there is oil.
When restarting it won't fire until there is fuel, and therefore oil, present.
The oil is only a vapour mist, not positive pressure lubrication and when starting from cold, whilst wear may be a worry, the surfaces are not hot so contact is minimal.
The oil misting is better when running than during the slow turning over of a hand start so you could argue that it's better to start the motor in a couple of pulls rather than wind it over endlessly when it won't start.
What does kill a motor, any motor, is to rev them immediately after starting. It can be a fine balance between pushing the choke in too far or not. I always try to warm up the motor at lowish revs, just leaving it running as I untie things and prepare to cast off.
There was a school of thought in vehicle engines that you should move off, under light load , as soon as possible to reduce wear.
I never subscribed to that, and on a boat it is much wiser to have the motor warmed up and ready for work because leaving moorings etc is the time that you really need it to work properly.
 
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If you run your 2stroke outboard out of fuel at idle speed there will be plenty of unburnt oil to lubricate it ( with possible exception if you are running a 100:1 mix)

Not relevant to this thread but is recommended that motors with multiple carbs are not run out of fuel. The design of the fuel system means that the top carbs can run out of fuel before the lower ones. This results in the top cylinders being driven with little or no lubrication by the lower ones until the engine dies
 
Lots of useful replies, but still no conclusive reason why my motor failed to start the two times it had just been transported on it's side, but 2 hours later, with nothing done to the engine, it started and ran fine.

My problem is at the moment I have virtually zero faith in this motor. That's fine for leaving the harbour, I can start it (if it will start) and run it to warm up thoroughly before setting off. But for returning, I think I better have the hook at the ready in case it won't start.

My problem for launching from the slipway is I need the motor to start reliably so I can motor from the slip to the harbour. This time, as it happened the tide was lower than we expected (high pressure) and we drank too much tea before launching on a falling tide, so it was so low, I simply walked in my waders and pulled the boat to the harbour. The fact the trailer was actually off the end of the slip by the time she floated is another story :)

So what can I do to find out why my motor is so tempremental?
 
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Is this a motor with an integral fuel tank. If so make sure the fuel tap is shutting off the fuel supply properly ... just wondering if fuel is dribbling from the tank, via the carb into the crankcase while its lying down esp if the tank is pressurising a bit during transportation (the float valve will stop it while its upright)

Surely you are Ok for the return trip because it has not been lying down?

On the other hand you say it seems like fuel starvation. Maybe the fuel is taking longer to flow and fill the carb bowl than you think ( not so if its remote tank of course) Filter clean?
 
If you didn't run it dry, then laying it on its side will drain the float bowl - are you giving it enough time to fill again before trying to start it? Is there something restricting the flow of petrol to the float bowl? (Filter, as suggested above, or rubbish on top of float needle).

Tempremental 2 strokes usually = muck in carb or (less often IME): plug.

Andy

(Great minds think alike / fools seldom differ - you choose, Vic :) )
 
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You may have something there.

It's an internal tank.

I'm pretty sure the fuel tap is turning off okay.

BUT I also think I have a very small fuel leak.

When I got the motor out for test, there was a small amount of petrol in the bottom of the motor. I think the leak is the little elbow rubber piece from the bottom of the tank to the tap. I think with the tank vent shut, on a hot day the presssure in the tank causes a small leak. The rubber is not split, it's just not a fantastically tight fit onto the bottom of the tank, so it weeps a little when under pressure.

Now I had just put this as a "to do later" rather than "delay launch" problem. My thinking being while afloat and engine upright, no need to close the vent, no pressure build up, no leak.

I can't think how it could actually cause my problem though, but worth mentioning in case someone can find a connection.
 
I know exactly what Dave means about no confidence in motors. I really detest a motor that won't do as it's told.
Like cars, cars with lousy brakes are a no-no.

It should be possible to clean and check everything and get the motor to a reliable state, but there will always be a lingering doubt.

Mind you. I bet you a new needle valve would fix it. They can be little buggers.
 
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Lakesailor said:
I know exactly what Dave means about no confidence in motors. I really detest a motor that won't do as it's told.
Like cars, cars with lousy brakes are a no-no.

It should be possible to clean and check everything and get the motor to a reliable state, but there will always be a lingering doubt.

Mind you. I bet you a new needle valve would fix it. They can be little buggers.
Click to expand...
mention of the needle valve prompted me to look at the carb diagram.

I see that there is a little clip that links the needle to the float. it pulls the needle off its seat when the float drops. Soft tip needles tend to stick.

It might be worth checking that this is in place.

Clutching at straws rather.
 
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