Engine turns over but won't fire

[ymiri]

Hi there,

I have an OMC sterndrive 3L 140 HP (1983 I believe - that's the age of the boat). I bought it new and needed work.
I turned the engine on once with the muffs on and it turned off after about a minute and since then won't turn back on.
I've replaced the spark plugs.
Checked the wiring.
Ordered new plug wires and cap and rotor but they're on the way...but I do get a spark.
One thing I noticed is that the ignition coil used to get warm when I have contact and running the radio but stays cold now. I'm not sure if that could be a problem.
Also, I tested the fuel pump by removing the fuel hose and turn the engine over and that spurts gas. I've also siphoned all the old gas and replaced it with premium has as well.
Any suggestions would be great.

Thanks!

 

[alldodge]

Re: Engine turns over but won't fire

Hi there,

I have an OMC sterndrive 3L 140 HP (1983 I believe - that's the age of the boat). I bought it new and needed work.
I turned the engine on once with the muffs on and it turned off after about a minute and since then won't turn back on.
I've replaced the spark plugs.
Checked the wiring.
Ordered new plug wires and cap and rotor but they're on the way...but I do get a spark.
One thing I noticed is that the ignition coil used to get warm when I have contact and running the radio but stays cold now. I'm not sure if that could be a problem.
Also, I tested the fuel pump by removing the fuel hose and turn the engine over and that spurts gas. I've also siphoned all the old gas and replaced it with premium has as well.
Any suggestions would be great.

Thanks!

:welcome: to iboats

It ran previously then stopped and would not restart. You stated you are getting spark but then engine will not start. The fuel pump is pumping so this is good. You drained the gas and put in fresh, which is good, but did you flush out the fuel lines and carb?

My first thought is that you have a fuel issue, in that you may not be getting fuel through the carb and into the engine. Need to take the carb off and clean it out. If anything else take the top off and look in the bowl to see what is there.

 

[southkogs]

Re: Engine turns over but won't fire

Are you hearing the starter clicking at all or is it turning? Are you sure the drive isn't seized up (upper gear case on a Stringer is always turnin')?

 

[ymiri]

Re: Engine turns over but won't fire

Are you hearing the starter clicking at all or is it turning? Are you sure the drive isn't seized up (upper gear case on a Stringer is always turnin')?

It's turning just not starting. The belt and wheel turn but that's it.
I did a compression test today and I see around 125 on two cylinders and 120 on the other two.
I cleaned all the wires and rotor as well.

I've removed the cap off of the carb and it looks clean inside (although I'm not too sure what else to look for in there).
I'm a little hesitant to completely remove the carb because I don't have much experience with carbs and I'm not sure how complicated it would be but do you think a carb cleaner would work as well?

I'll test the suggestion of cleaning out the fuel lines as well.

Thanks!

 

[alldodge]

Re: Engine turns over but won't fire

It's turning just not starting. The belt and wheel turn but that's it.
I did a compression test today and I see around 125 on two cylinders and 120 on the other two.
I cleaned all the wires and rotor as well.

I've removed the cap off of the carb and it looks clean inside (although I'm not too sure what else to look for in there).
I'm a little hesitant to completely remove the carb because I don't have much experience with carbs and I'm not sure how complicated it would be but do you think a carb cleaner would work as well?

I'll test the suggestion of cleaning out the fuel lines as well.

Thanks!

Take a very little but of gas and put it in a cup, maybe 2 to 3 ounces. Pour the gas down the carb and then crank the engine over and see if it will start

 

[ymiri]

Re: Engine turns over but won't fire

Take a very little but of gas and put it in a cup, maybe 2 to 3 ounces. Pour the gas down the carb and then crank the engine over and see if it will start

THANKS SO MUCH! That did it. It ran smoothly for 10 min, I played with the throttle and now it turns on for a second and turns back off.
I'll tinker with it though it looks like that was the source of the problem!
I have a quick question though, this was capped when I got the boat, is this the exhaust or should it stay capped?

 

[alldodge]

Re: Engine turns over but won't fire

THANKS SO MUCH! That did it. It ran smoothly for 10 min, I played with the throttle and now it turns on for a second and turns back off.
I'll tinker with it though it looks like that was the source of the problem!
I have a quick question though, this was capped when I got the boat, is this the exhaust or should it stay capped?

View attachment 232022

Looks like you have a fuel delivery problem, look at the pump, filters and lines. The pickup tube in the tank could also be an issue. If all else fails get a gas can and run the fuel line into it.

So far as the cap I just don't know. Looks to be a cover for part of the bell housing. If it can be removed without breaking it, have a look

 

[southkogs]

Re: Engine turns over but won't fire

...this was capped when I got the boat, is this the exhaust or should it stay capped?

I'm not sure what that is - mine doesn't have it. It's not exhaust though. Your exhaust is that big hole straight out the back of the intermediate and into the stern drive. You should be fine to cap that back up.

I know you said you were seeing fuel pump at the fuel pump, but I had a similar situation this year and it turned out to be a leak in my fuel line. You may want to add that as something to check.

 

[Maclin]

Re: Engine turns over but won't fire

What is your starting procedure, such as , do you pump the throttle a couple of times before cranking? That is a must especially when dead cold, not so much if the engine has been run that day and is still warm.

 

[ymiri]

Re: Engine turns over but won't fire

What is your starting procedure, such as , do you pump the throttle a couple of times before cranking? That is a must especially when dead cold, not so much if the engine has been run that day and is still warm.

Thanks for all the help. About the starting procedure, I usually don't pump it because I'm afraid to flood the engine but I'll try that out.

 

[Idlespeedonly]

Re: Engine turns over but won't fire

One thing I noticed is that the ignition coil used to get warm when I have contact and running the radio but stays cold now.

When you say contact, do you mean the engine is running? If you just have the radio on and engine off, the points can be damaged by doing this.

 

[ymiri]

Re: Engine turns over but won't fire

When you say contact, do you mean the engine is running? If you just have the radio on and engine off, the points can be damaged by doing this.

Oh really? I never knew that. I usually work on it listening to the radio but the engine off (so basically like having accessories on in a car - key half turned). I'll avoid that then. I'm new to this stuff and learning a lot from this website. Thanks.

 

[Idlespeedonly]

Re: Engine turns over but won't fire

The coil should not be energized if the key is turned to the accessory position. It can damage the points and also mess up the coil.

 

[Maclin]

Re: Engine turns over but won't fire

Thanks for all the help. About the starting procedure, I usually don't pump it because I'm afraid to flood the engine but I'll try that out.

That (pumpiing throttle) is essentially what you did when trying AllDodge's advice of pouring the fuel into the carb

Pumping the throttle a couple of times won't flood unless it was already overloaded. If you think it is flooded open the throttle all the way (in throttle only mode) and crank for up to 10 seconds or so to clear the flooding, be ready to throttle back when it catches.

 

[ymiri]

Thanks for everyone's help. I followed everyone's suggestions and it was a gas delivery problem. Once everything was cleaned now it's turning on consistently! Good luck to everyone else this season