15hp Evinrude starting troubles E15RCRM

[EricB]

OK this is my first post to these forums so be gentle!!!

I have a 1980(?) 15 HP Evinrude (model E15RCRM) that is having starting issues. When I first started looking into it I found that I was getting spark and getting gas to the carb but it would still not turn over. No fire at all. I did some digging and found that the shear key on the flywheel shaft was broken. I replaced the key and instantly it fired up. Now the issue is it will not stay running. It fires up almost every pull runs for about 5-10 seconds and dies. I tried all of the following to no avail. The problems still exists.

- New plugs
- Fresh gas and a new fuel line (I first thought the fuel line was not seating properly and air was getting into the line. Not)
- Pulled carb and cleaned it along with the jets
- Checked the float and float needle
- Adjusted idle screw
- Adjusted the Air/fuel mixture screw

I have run out of ideas so now I turn to you, fellow enthusiasts, for other ideas. One thing I'm not sure about is the air/fuel mixture screw and how it should initially be set. I turned it all the way in (lean) and backed it off about a half a turn. Is this correct? I tried turning it out a half turn between each start until all the way out (rich). No matter the position I got the same result. Is it possible the fuel pump is bad?? Is there a check for this?

Any help you guys (or gals) could provide would be greatly appreciated.

Many thanks in advance.
Eric B
Racine, WI

 

[Joe Reeves]

Re: 15hp Evinrude starting troubles E15RCRM

Your engine is a 1984 model, not a 1980.

I assume that you are choking the engine initially, and then it starts, then runs on only what fuel entered the crankcase via choking. This indicates that fuel is not passing thru the fuel passageways in the carburetor.

Double check your carburetor work as it's easy to overlook something.

(Carburetor Adjustment - Single S/S Adjustable Needle Valve)
(J. Reeves)

Initial setting is: Slow speed = seat gently, then open 1-1/2 turns.

Start engine and set the rpms to where it just stays running. In segments of 1/8 turns, start to turn the S/S needle valve in. Wait a few seconds for the engine to respond. As you turn the valve in, the rpms will increase. Lower the rpms again to where the engine will just stay running.

Eventually you'll hit the point where the engine wants to die out or it will spit back (sounds like a mild backfire). At that point, back out the valve 1/4 turn. Within that 1/4 turn, you'll find the smoothest slow speed setting.

Note: As a final double check setting of the slow speed valve(s), if the engine has more than one carburetor, do not attempt to gradually adjust all of the valves/carburetors at the same time. Do one at a time until you hit the above response (die out or spit back), then go on to the next valve/carburetor. It may be necessary to back out "all" of the slow speed adjustable needle valves 1/8 turn before doing this final adjustment due to the fact that one of the valves might be initially set ever so slightly lean.

When you have finished the above adjustment, you will have no reason to move them again unless the carburetor fouls/gums up from sitting, in which case you would be required to remove, clean, and rebuild the carburetor anyway.

 

[Xcusme]

Re: 15hp Evinrude starting troubles E15RCRM

Eric, Welcome to iboats !

I have a '79 15hp 'Rude.

You mentioned that you adjusted:

- Adjusted idle screw
- Adjusted the Air/fuel mixture screw

I'm concerned with the 'idle screw'. Are you talking about the small phillips screw on the top of the carb, just below a small roller?

 

[EricB]

Re: 15hp Evinrude starting troubles E15RCRM

Hey Joe,
Thanks for the great info! I guess I'll have to try pulling the carb off again. Is there any special nook to look for in Particular? I sprayed an entire can of carb cleaner into every little hole I could find and everything seemed be flowing properly. Then I followed that up with compressed air. Took the Jets off and soaked them in the cleaner as well before re-assembling the thing.

I'll give it another shot and see what happens. But you dont hink this is related to the fuel pump at all?? Just want to be sure.

Thanks.
Eric

Your engine is a 1984 model, not a 1980.

I assume that you are choking the engine initially, and then it starts, then runs on only what fuel entered the crankcase via choking. This indicates that fuel is not passing thru the fuel passageways in the carburetor.

Double check your carburetor work as it's easy to overlook something.

(Carburetor Adjustment - Single S/S Adjustable Needle Valve)
(J. Reeves)

Initial setting is: Slow speed = seat gently, then open 1-1/2 turns.

Start engine and set the rpms to where it just stays running. In segments of 1/8 turns, start to turn the S/S needle valve in. Wait a few seconds for the engine to respond. As you turn the valve in, the rpms will increase. Lower the rpms again to where the engine will just stay running.

Eventually you'll hit the point where the engine wants to die out or it will spit back (sounds like a mild backfire). At that point, back out the valve 1/4 turn. Within that 1/4 turn, you'll find the smoothest slow speed setting.

Note: As a final double check setting of the slow speed valve(s), if the engine has more than one carburetor, do not attempt to gradually adjust all of the valves/carburetors at the same time. Do one at a time until you hit the above response (die out or spit back), then go on to the next valve/carburetor. It may be necessary to back out "all" of the slow speed adjustable needle valves 1/8 turn before doing this final adjustment due to the fact that one of the valves might be initially set ever so slightly lean.

When you have finished the above adjustment, you will have no reason to move them again unless the carburetor fouls/gums up from sitting, in which case you would be required to remove, clean, and rebuild the carburetor anyway.

 

[EricB]

Re: 15hp Evinrude starting troubles E15RCRM

Thanks for the Reply. The idle screw i have been adjusting is a small allen head srew on the plastic roller assembly. I dont think there is a phillips screw on top of my carb. that could be because it's an 84 insteadof an 80 like Joe mentioned.

Thanks,
Eric

Eric, Welcome to iboats !

I have a '79 15hp 'Rude.

You mentioned that you adjusted:

- Adjusted idle screw
- Adjusted the Air/fuel mixture screw

I'm concerned with the 'idle screw'. Are you talking about the small phillips screw on the top of the carb, just below a small roller?

 

[Xcusme]

Re: 15hp Evinrude starting troubles E15RCRM

I kinnda thought that was the screw you were talking about. That's not an idle speed adjustment screw, That screw is used to set the sync and link. That roller syncs the throttle with the spark advance of the motor.
You can make the proper adjustment (without the motor running) by advancing the throttle until the roller aligns with a mark on the cam that the roller rides on. With the mark centered on the roller, adjust the screw until the throttle plate just starts to open. It's often hard to see when the throttle just starts to move (open). To help 'see' this movement, you can use a small alligator clip (with a short length of wire attached). You clip it onto the end of the throttle shaft, this amplifies it's movement and is easy to see when it just starts to open. I have used a very small tyrap (approx 3") too. I attach the tyrap to the end of the throttle shaft and the tag end of the tyrap serves as the indicator. Since the tyrap is so small, I just leave it attached when I'm done. Onee you make this adjustment, there's no reason to change/check it unless you remove the carb.

As Joe has already mentioned, you may have missed something in the carb. Removing and cleaning under the core plug (small plug on top the carb) can help too. All the parts needed come in a carb rebuild kit. The small holes into the carb throat, directly opposite this core plug affect the idle circuit of the motor.