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Starting trouble

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donaldboyer

Contributing Member
Hello,

I am having trouble starting my outboard. It's hard to start when it hasn't been run for a day or several weeks or months (starts fine when hot). Sometimes I need to crank it for 20 - 30 seconds. The enricher is fuctioning (i use it to stop it from stalling at idle when cold for the first 1/2 minute or so). I am pumping the bulb until it is too tight for me to pump anymore, trying to force more fuel through.

This happens when it's been trimmed right in, but seems worse if it's been tilted fully up (like on trailer) Could fuel be draining out of something?

I have tried leaving the idle lever at idle or at 1/2 throttle to see if there is any difference, but Im not sure.

Is this normal cranking time? Am I just worrying about nothing?

What is the correct procedure for starting this kind of motor (throttle setting etc etc)

Thanks!

Donald

Mercury 90hp
1988
3cyl 2 stroke
Triple Carb
98 octane fuel
In excellent order (kept covered etc)
 
30 seconds before she fires sounds a little long.

It could be that you are just not engaging the enricher long enough before you try to start.

It is just a gravity feed system that sorta leaks fuel into the intake.

So, unless doing so already, hold the key in for 10 full seconds before hitting the starter - if that makes a little difference but it's still not perfect, move up to 15.

There could be some minor varnish build-up that is slighly restricting the flow - an additive to the gas at this point certainly wouldn't hurt (any carb/throttle body cleaner that is rated for 2 stroke use)...
 
30 sec is a little long for a 90. The carb jets may be a little clooged or the idle fuel screws set a little lean. You can try to adjust the #2 and #3 carb needles an 1/8 turn richer.
All outboards are harder to start tilted up, because the gas runs out the carb throats instead of downhill into the back of the engine.

What I would do is de-carb the rings with seafoam too. 20+ year old motor is probably coked up inside sticking the rings.
 
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Ahh! I didn't know about using the enricher like that for 10secs. I just pressed key in (that engages enricher on my motor) and turn the key instantly. For my interest, at the throat entrance to the carbs (in front of the butterfly? valve thing there is a tiny tube poking up through into the throat, is that where the enricher pumps the fuel into?

Seafoam: have heard mixed things about this.... but mostly hear-say and rumours. What's the story with this stuff? Is it safe to use, what does it do, how does it work etc......

Thanks for the input!
 
No the enricher feeds behind the plates (butterfly) pretty much right where the carb bolts to the intake so even if they are throttle plates are totally closed the intake still gets some gas (and depending on the carb body in use, the idle jet and possibly an intermediate or air jet will also feed channels that end up behind the butterfly.

That "tube" you note in front of the butterfly is how the gas gets to the carb throat from the main jet located down in the float bowl - the gas supply for "off-idle" running.

And SeaFoam is more than safe to use - among it's other qualities it also helps keep carbon out of the cylinders and exhaust.

The closest thing to "tune up in a can" for outboards...
 
Holding the key in (with it on) for 10 seconds usually solves hard starting problems with those old mercs. They are very hard to flood so don't worry about that.
 
Brilliant! Your advice is fantastic, thank you!

I will get some Seafoam to run through it. However, I don't want to spend the whole weekend on the lake with a smokey motor, so how can I use Seafoam at home with the muffs to clean the motor in one quick hit?
 
No, it's kinda a "run a whole tank of gas" solution.

If you want the "fix the cooties right now solution" pick up a spray can of Merc's "PowerTune" (about 5 bucks) - it's sprayed directly into the carb throats while running on muffs - just follow the can directions.

If you don't have a Merc dealer close, BRP/OMC and Yami have similar products - just look for a spray can (same size as a can of spray paint) that is advertised for removing engine carbon.

It won't give you the same (total fuel system cleaning) that Seafoam will, but it's great stuff for getting the gunk out of the crankcase, intake and exhaust ports and all the carbon from the cylinders/pistons.

For me, PowerTune is standard kit when bringing motors back to service after they have been stored or layed up for the winter...
 
How smokey does Seafoam make the engine while you are running a bottle through your tank? (when used to the correct quantities)
 
When added to the gas, just a bit, not bad at all, like running rich mixture. But with the sea foam, you want to let it sit in the engine for a bit, after running with it. It wont hurt to mix a "strong batch",. but really, read the directions on the can. You can get it in a lot of autoparts stores too. I had put in directly into the carb of my crusader, talk about a bit of smoke...
 
OK, small problem, I emailed Seafoam and they have replied telling me that Seafoam is not available in New Zealand. So would any good quality carb/fuel line cleaner do the same thing?
 
what about merc's powertune as Galamb suggested? Is that available?
West Marine carries is as I'm sure a bunch of other places too.
 
Seafoam is kinda a combination carb/injector cleaner and decarb all in one.

If you have a Yamaha dealer around they have a product called (ring-free) which is kinda/sorta the same thing.

Or as I mentioned, Powertune from a Merc dealer (which is mostly just a decarb formula), but if you used in with the addition of a carb cleaner in the gas you would have the "made at home" version of SeaFoam...
 
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