Evinrude 15hp PLEASE HELP?

[rybo]

Hi everyone. I'm new to the forums and new to outboards generally. I've just recently bought a 1991 15hp evinrude tiller steer. She had been setting up for a few years and got a pretty good deal on her. I'm running her on a 14ft. john boat. Motor initially started right up and ran well for a couple weeks and fishing trips with new gas, grease, etc.

Finally, she began to cough and throttle out when I would turn it up. Then it would start up and cut out everytime when I opened up the throttle. I took it in to the local repair shop and they put a carb kit on it. I got it back and took it out for the first time and she ran pretty smooth, but not as fast as it seemed to go at first. Probably topping out around 18mph when it used to plane the boat off at around 25mph. I'm not looking for speed, however, I do want a dependable well running motor as we all do.

Today I took it out and it shortly began doing the same cutting out when I opened up the throttle. It seems to idle fine, but when I open it up it cuts out. Out on the lake today and needed to get back to pier through the wind. I finally resorted to messing with the mixture/lean switch and turned it up about a 1/4 from where it was set and it took off fine and ran well back to the pier at about 18-19mph. I throttled down and throttled up a few times to check it and it seemed fine after I increased the mixture. I don't know if it is good to run it at a higher mixture and if it would hurt it in the long run. Also, when in neutral and I throttle it all the way up, it begans "clanking" a little when I throttle back down. Only does this in neutral.

Before I take it back to the shop and complain about spending $100 on the carb kit, I wanted to get some suggestions. By the way, when I say "mixture," I mean lean/rich adjustment.

Thanks for all help.

 

[rybo]

Re: Evinrude 15hp

Re: Evinrude 15hp

any ideas??

 

[Rick.]

Re: Evinrude 15hp PLEASE HELP?

Well by your own admission the carb. kit made a difference. The lean/rich is for your slow speed idle so it should not have any affect on your high speed performance. To get it right for idle have the motor at idle, in forward gear and start turning it in in 1/8 increments until your motor starts to sneeze. ( It will sound like a momentary miss every few seconds) From there turn it richer about 1/4 turn and see if it runs without sneezing. If it does leave it there forever. Not sure why you've lost top end speed. Are you carrying any additional weight than before. Loading your boat differently or changed the trim angle on the transom mount? All the above can make a difference. Are you being sure to open the gas tank vent? Try pumping the bulb and see if it speeds up. Let us know. Rick.

 

[freddyray21]

Re: Evinrude 15hp PLEASE HELP?

I am guessing that has a fixed high speed jet. It almost sounds from your description that it does not. does it have one or two mixture screws? If so the lower is the high speed and changing that mixture will affect the motor as you describe.

 

[tashasdaddy]

Re: Evinrude 15hp PLEASE HELP?

classic case of the contaminated carb. carb cleaning and revuild kit, while you are at it replace all your fuel lines with alcohol resistant fuel lines. from tank to carb.

 

[rybo]

Re: Evinrude 15hp PLEASE HELP?

Thanks for all the replies. I've just had a carb kit put on it at local reputable marine shop. Like I said, it ran better for a day. Then just yesterday started to cut out when I opened up the throttle. I would have to turn back the throttle to keep it from turning off completely. When I adjusted the lean/rich setting about 1/4 of a turn "up" or "counterclockwise" toward the greater value, it opened up and ran like a champ. I don't know much about the carb or adjustments there, but I'm pretty mechanical and willing to learn. I've just never had an outboard to work on!! I've been reading and reading about them and downloaded a repair book last night. I've got to get a hose attachment to run it out of water before I can really tinker with it at the house. I'm also going to call the boat place that put a carb kit on and quiz them about what they did or did not do. I assume that putting a carb kit on, means cleaning all the jets or replacing them. The gas tank vent is open. I've read on here that taking the cover off while running can be a tell-tale sign of exhaust issues. May try that.

Thanks

 

[bankerjohn]

Re: Evinrude 15hp PLEASE HELP?

Re-building the carb back to "factory new" would be a waste of time and money if your fuel lines have deteriorated to the point of shedding pieces and introducing them into your newly re-built carb. Have you replaced the fuel lines inside the cowl? how about the lines from the tank to the motor?

No guarantee that this is your problem ... could be fuel pump not supplying sufficient fuel, fuel pump blocked by debris restricting flow, air leak in one of the lines, etc. ... but it definitely sounds like it's a "lack of sufficient fuel" problem, whatever the cause.

 

[Whoopbass]

Re: Evinrude 15hp PLEASE HELP?

If you got the fuel tank with the deal clean it out and then put fresh fuel mix in it and then stick a small nail in the end of the fuel line connector and flush out all of the old gas in the line/bulb.
With your clean tank/fuel line hook it up to the motor and with the fuel line removed from the carb flush out the system with several squeezes of the bulb.
You will probably want to inspect the fuel pump for any crud before doing this.

Sounds like you will probably have to remove the carb again and clean out any contaminants that are in it. That carb is easy to work on. The hardest part is dealing with the starter recoil. You have to remove it to get to one of the nuts on the carb unless they make a specialized tool to get to that nut. The recoil assembly is easy to remove but it takes me a few tries to get it lined back up correctly to get the bolt back in.

Check out the FAQ section for instructions on how to rebuild that carb.

 

[Rick.]

Re: Evinrude 15hp PLEASE HELP?

New fuel lines would be a ggod idea. If your keen to learn have a look at this link. I consider it a must read for any 9.9 or 15 OMC owner. Enjoy. Rick.
http://forums.iboats.com/showthread.php?t=158087

 

[rybo]

Re: Evinrude 15hp PLEASE HELP?

Thanks for all of the replies. I took it out today again to see what would happen after the rich/lean setting got me back to the pier good yesterday. She ran good and opened up well. I drove around the lake an hour or so seeing if she'd bog down again. Everything running well for a time, then I slowed down a little and she began bogging a little when I hit the throttle. I adjusted the rich/lean again and it ran fine for the rest of the day.

I just don't know what could be causing the now occasional bog at slow speed. I have brand new tank of gas/oil and inspected lines and bulb. They are practically new. The bulb I've heard can get stuck or not operate properly. Do these have a "fuel pump?" I thought they were controlled by suction from the tank and bulb? Anyway, thanks again for the replies and any more suggestions.

R

 

[Whoopbass]

Re: Evinrude 15hp PLEASE HELP?

Yes it has a fuel pump. Just follow the fuel line from the carb to the black plastic box with a round stainless steel screw.

Your mechanic may have just sprayed out your carb with some cleaner and threw a kit on it. Sometimes you need to soak a carb in cleaner for a day or two and clean out any passages with a thin wire to remove any buildup.

 

[rybo]

Re: Evinrude 15hp PLEASE HELP?

yeah, you may be right. I talked to mechanic today again and he said they put a kit on it and clean jets. Charge 134 with tax. Damn, they shoulda got it running a hell of a lot better than this!! I mean it runs well once it "kicks" in, but I still get that bogging down thing sometimes...frustrating. How hard is it to remove carbureator and all? I've been reading all the manuals, etc., and it seems there is a lot more to it than a few screws. I think I have to remove the rope pull pulley and all that and then make sure timing is aligned when putting it all back together. All that to get to carb??

Thanks

 

[film495]

Re: Evinrude 15hp PLEASE HELP?

you could try to run a can of engine tuner through it - costs less than 10 bucks. just spray into the carb air intake while running - pretty easy stuff, just follow the directions on the can.

 

[rybo]

Re: Evinrude 15hp PLEASE HELP?

Went and bought a couple of those "earmuffs" so I could run it at home and analyze the inside today. I looked everything over good and squeezed the bulb to make sure gas was circulating through all tubes properly and getting to carb. It was. The only thing I notice was the screw on the fuel pump was not really tights, so I tightened it down good. I ended up pretty much just playing with the rich/lean setting. I cranked it all the way up and down and finally found a spot where it wouldn't cut out when I hit the throttle past midway. It will rev like hell, but it seems like it takes a second ot get there after I twist the throttle. It's almost like it is idling and when I turn the throttle up, it hesitates and THEN revs to high speed...Any thoughts?

 

[Whoopbass]

Re: Evinrude 15hp PLEASE HELP?

Removing the carb is easy. You don't have to mess with the timing.
Like I said before, the hardest part is dealing with the starter recoil and its not even that bad.
Take that carb off and soak it in a solvent for a day or two.
There is plenty of instructions on here. Just check the FAQ section or do a search.

 

[rybo]

Re: Evinrude 15hp PLEASE HELP?

Thanks for all of the replies. Before I go delving into the deep sea of Carburetor cleaning, I think I might take it back to the shop that put the "kit" on and complain enough so that they will do it over or clean it better b/c it is practically doing the same thing it was before the kit. By the way, does anyone know where I can get a spare "low speed" knob that fits on the outside of the motor by the choke? The threads on the plastic part of the knob don't seem to want to turn the needle anymore. They may be stripped. I've checked the evinrude site, but they don't sell just the knob...Also, does anybody have any ideas what it could be beside the carburetor or is everyone fairly certain it is something to do with the carburetor and gas flow. Again, it seems to be flooding out when I accelerate the throttle past a certain point. It's about midway open when it begins doing this. The only time it doesn't is when I increase the rich/lean setting to almost as high as it will go...I'm assuming it's not getting enough gas because when I turn the knob counterclockwise to open up the needle more, it gets more gas, correct? Am I thinking about this correctly? Counterclockwise, more gas, clockwise more air? Thanks

 

[Rick.]

Re: Evinrude 15hp PLEASE HELP?

Counter = more gas
Clockwise = less gas
Neither adjusts air. Have you ever pulled your plug wires when it is bogging down to confirm spark to both plugs while your experiencing the problem? Rick.

 

[rybo]

Re: Evinrude 15hp PLEASE HELP?

Not sure I could be that quick on the draw, Rick. I would have to be running the motor and twisting throttle when I pull wires? How would I tell it was sparking correctly? If I pull wires, wouldn't it shut off? Sorry for my little intellectual knowledge of these small motors. Thanks.

 

[rybo]

Re: Evinrude 15hp PLEASE HELP?

The idle knob on end of tiller steer...what the heck does that do? I twist mine both ways and it really doesn't seem to do anything....

The more I think about it, the more I want to change every fuel line on the motor as well as gas tank just b/c it is a 1991 and has set in a garage for years without running. It seems like it is wanting "more" gas when it goes high throttle. Seems like it is "starving" for gas when I hit the throttle, that is why I've had to increase the rich/lean setting almost all the way to get it not to cut off (counterclockwise).

I've also noticed that when I turn the throttle up and it actually doesn't bog down (b/c the rich/lean setting is all the way up), it hesitates a minute before kicking into higher rpm's. It's like I twist the throttle and watch the wheel turn and then about 1-2 seconds later, it kicks in.

I'm kind of thinking more cloggage in jets even though the damn mechanic was supposed to clean it out and put kit on it.

Thanks for bearing with me as I try to explain this the best I can...

 

[Rick.]

Re: Evinrude 15hp PLEASE HELP?

Go easy on your mechanic. Some day you will need him again. To be honest he may have done a fine job with the carb. kit. and a milli second after it could suck in debris from the gas line and your back to square one. Not his fault you see. I know I've had to clean a carb. more than once and I know I was very thorough the first time. THe idle speed knob on your tiller is for trolling. If you determine you want to go a certain speed you can dial it in with the knob. Then you can boot around the lake changing locations run to shore for a pee and a picnic and when you throttle down your speed will be exactly set at the speed you determined earlier. A truly fantastic feature I think. I'm not sure yours will work until you get that carb. cleaned and your slow speed needle properly adjusted. Best of luck. Rick.