40 HP Mariner.. Need some help.

[dyeguy1212]

Well this is my first outboard, and I have a lot to learn. It runs pretty good, but can be tough to start some times.

It seems like its either a slow idle, or its not getting enough gas. It turns over and wants to start almost immediately, but dies off before it gets going. I then flip up the fast idle lever, and it starts right up. When I push it back down, it sometimes putters out, or will allow me to put it in gear. It happens almost every time I start it. Once I get it going, it runs perfect.

Any suggestions? Saying "Clean the carbs" doesn't help, because I don't know how to do it. I've read through the maintenance book, and it offers great help, but doesnt show where any of this damn stuff is. Like I considered toying with the screw that adjusts the idle, and it gives a great description of how to adjust it properly, but now where the godforsaken screw is located on the engine... idiot authors.


So any advice? If it turns out to be a tough job I'll probably just wait until the spring..

 

[Loggerhead Mike]

can you post a pic of the motor w/ the cowl off?

when you adjust the idle screw just go a 1/4 turn at a time. mark the screw before you start so you can always go back to the origional setting. when you turn the idle screw you have to give it a minute to burn the gas out of the crank before you'll notice any difference.

if you turn the screw clockwise (in) it will lean the motor out, vise versa

 

[Bubba]

Does it just do this when the motor is cold(not been running for a day or so)? Or everytime you cut the motor off?

 

[Zum]

I was thinking the same as Bubba.
Maybe it just needs to warm up a bit?
If it works good after alittle warm up,I'd might not touch it.

 

[wasilvers]

If it's your first outboard, this might be a starting proceedure that you just need to get familiar with. Mine is below

• 
  1. Pump the primer bulb in the fuel line till it is firm
  2. Prime motor for 5-8 seconds - mine is push the key in while in the 'run' position
  3. Raise fast idle lever
  4. Crank engine till it starts - about 1-3 seconds
  5. Adjust fast idle lever for 1000-1200 rps for a minute or so - gotta let the engine warm up (usually this is 10-20 seconds in real life)
  6. Drop idle lever to standard position and listen to her purr

If your engine is like mine, it has no automatic choke. A choke lets the engine run richer till it warms up. Most cars have these built in now, so the art of starting a motor is a forgotten thing. By raising the idle lever, you are giving it more fuel to run till it warms up. If the weather is cooler, you might need to let it warm a bit more before she'll stay running. My guess is, if it runs fine once it has been running as you said, it just needs to warm up a bit before you use it from a cold start.

If you feel the need to adjust the idle screw, follow your throttle line to the engine connection. Move throtte forward and backwards, (engine off) and see where the rotating plates rest agains at idle. Usually your idle screw is here. It usually just advances the throttle a bit, like the idle lever on your control box.

Things that make my motor not idle are forgetting to vent the fuel tank and forgetting to vent the fuel tank. Yeah, I forget a lot, then wonder why she won't idle nice after a long run back to the dock.

Good luck,

Will

 

[dyeguy1212]

Its not the fuel tank vent.. surprisingly enough I havent forgotten to do this.. yet.

To answer the unanimous question, it is every time I start it up. I follow the similar starting list mentioned by wasilver, and it will normally get up and going pretty quick. I'll make a long run to my fishing spot, fish for probably a half hour max, and then I'm ready to hit up another spot. I go to start the engine, and it will turn over and sometimes start for a no more than 2 or 3 seconds. I then push the key in (choke), and it will start up for another 2-10 seconds, before puttering out (or it will run sort of slow, almost bogged down, and then when I put it in gear, it slowly dies off).

Its not a BIG deal, because it has yet to not start within 30 seconds or so, but its time I could be fishing :lol:

 

[Zum]

Hmmm...maybe you havn't found the sweet spot yet.
I should start good after alittle run and I wouldn't think you would have to choke it after alittle fishing.
Might need alittle carb work,run some seafoam through it first to see if that might help.

 

[Loggerhead Mike]

pull the plugs and see if they have carbon on them. dont replace just hit them with a wire brush if they're dirty

sounds like your carb needs adjusting or rebuilt

 

[wasilvers]

Hmmm...maybe you havn't found the sweet spot yet.
I should start good after alittle run and I wouldn't think you would have to choke it after alittle fishing.
Might need alittle carb work,run some seafoam through it first to see if that might help.

Agreed - if I've had the engine off for a while, sometimes the fast idle is needed to start it, but not a choke. Try the seafoam first - I hear it can work wonders. And if you have the ability to build a lego house, you can work on an engine. Carbs are pretty easy, just gas running in, and being drawn out as a mist. I've cleaned a number of them on a lot of different engines. Just don't lose anything and clean it gently - carb cleaner, compressed air and a toothbrush work wonders.

My guess is you have a leak in the fuel system somewhere and when it sits, the pressure in the system is lost, but then you'd likely be sucking air in and wide open throttle would likely be messed up. Maybe a bowl on one of the carbs is leaking a bit from the top seal? But an engine can run a minute or two at idle with the fuel in the bowls - Assuming your carb has a bowl. Hmmm

Ok, maybe it's just a simple thing such as fuel pressure. Next time it doesn't want to start like that, give the bulb a squeeze. It it is more than a half squeeze, your fuel line doesn't have the pressure it needs and your fuel pump is working hard to try to suck the air out and get gas at idle. Higher rpms would cause the fuel pump to work harder and small issues would be masked. The bulb is a one way valve and should hold the fuel line and bulb full of fuel. Fuel can't compress much so a half squeeze is all it should take to get to firm. If it takes more, I'd try replacing the fuel line and bulb. Hopefully it's an easy fix like this - if not, well clean carbs and rebuild fuel pump. I think that if you run fine once started and at WOT, you might just have a little leak somewhere.

Will (not a mechanic by trade but dis-assembled and reassembled my first motor at 9 - rebuilt my first car engine at 15 - and still picking up junk on the side of the road just to take it apart and get it running)

 

[huntinfool]

I'd say that you have something plugged up in your idle jets in your carb. If your not familiar with motors or how to work on them I'd suggest finding someone who is and asking them to help you. Offer to pay them or at lease buy them a cold one and they can walk you through taking the carbs off and cleaning the jets. If you were closer I'd come by and give you a hand...