Boat Motor Problems.... I need some advice

[FISHINGURU]

ok i got a 30hp honda 4 stroke...just got an oil change, oil filter, new spark plug, and some new lower end lube put in.

i had this same problem before the new stuff was put in but i just wanted to update ya on what has been done to the motor recently.

ok it's electric start and fires up instantly like a champ...purrs like a kitten..you can barely tell she running.

i give it some gas and it takes off pretty nice with some power but at about half throttle she just stops there...it still runs but there isn't much difference between half and full throttle.

she sounds bogged out after half throttle....so if i'm full throttle goin across the lake its a muddled sound then i can tell she snaps out of it for a second and sounds more crips and my speed picks up like it should normally be...but then it bogs back down.

the other part is if i try to troll at slow speeds it will be just fine for awhile then all of a sudden it kills and won't start back up again until i crank on it about 10 times...like it flooded itself out or something....then she'll start back up like nothing happened and i can troll again for another 1/4 to 1/2 mile or so and it will do it again.

my gas is brand new..so i don't think it's that but it's kinda like a bad gas thing on how it bogs and cuts out...or maybe to much air...or something clogged or gunked up somehwere...i dunno much about motors so any suggestions? thanks

[Surface Tension]

If you pull the plugs and inspect them when its acting up under full throttle they should tell you if your starving for gas or fouling out. If your fouling out you'd be looking at carb issues or electrical.

I'm leaning toward starving for gas. Have you tried priming up the bulb when this happens at low speed? Start with air leaks in the fuel line or possible rotted pickup tube in the tank. After thats been checked to be good clean the fuel filter. Still acting up? Back to the primer bulb, are you having to prime it up after running. If so I'd rebuild the fuel pump. Next thing down the line is a carb cleaning.

[boatfixer]

Sounds like its starving to me too.

I always like to isolate the problem first. At half throttle and past, try tapping (don't hold it in, just tap it) the choke or squeezing the primer bulb. If the rpms pick up, its starving. If at that point it makes no difference, I hook up a timing light to each cylinder and watch the light as the motor bogs or cuts out. If the light goes out simultaneously, you have an ignition problem.

As far as the dying at idle, just as ST asked, do you have to re-prime the bulb? Also, do you have to choke to get it going again? do you smell gas?

Like Frank said, check all connections, lines, and primer bulb first for signs of leaks and replace if theres any question.

[FISHINGURU]

thanks guys...finally have some free time now from work...haven't looked at the boat or taken it out since the post.

i'll check all the lines and make sure they are clean, look for cracks, and look at the primer bulb...if i notice anything i'll fix or replace that before even getting on the water.

if i don't find anything wrong with that i'll take her for a spin and try pumping the primer bulb when i'm wide open goin across the lake.

i'll check the plugs because it could possibly be fouling out too instead of starving....maybe the carb needs a cleaning.

i'm kinda leaning toward something in the lines or in the tank, cracks,ect.

this boat was stored outdoors under a shelter for 2 years so there could very well be some weathered lines...i glanced at the lines for cracks when i was out on the water but i didn't search hard..i didn't see any but i'll take a closer look.

could actually be a couple of the ideas mentioned too...not just one lol

i don't really smell any stronger gas odors when it kills while trolling...i never tried pumping the primer bulb after it died...maybe if i tried that it would fire back up after a turn of the key again...i had to turn the key over 6-10 times before it would start again without doing anything to the primer.

i guess its either flooding or starving...i'll look everything over and do some testing...i'll keep ya posted....thanks again

[DinkADunk]

When I had my kicker installed (9.9hp Johnson) it would often die while near idle (trolling). After pulling teeth I got the dealer to rebuild the carbs under waranty as the motor was roughly a year old (sitting in the dealership) and had gas sitting in the bowl all that time. That initially fixed that problem. However, after trolling for awhile it will start to act up and die. When it does that I switch over to a small tank of gas that has 1.5g of gas mixed with a can of seafoam. I run that at various throttle postitions for 10 minutes or so and then I'm good to go for a couple more weeks of trolling. I believe that it starts acting funny after some buildup in the carbs. The overdose of seafoam seems to do the trick and reduces the buildup, allowing the engine to run as it should. You may have something similar going on.

[FISHINGURU]

UPDATE

took the boat out this week...tried pumping the bulb at full speed and didn't notice much..it seemed to help a little bit but not nothing to make you say whoa what a difference...so i went and bought a new line and bulb anyway since the old one did look rough.

got new gas and added some stabile...put the new line and bulb on...cleaned out some gunk i found in the airline..got all excited and took it out and same ol same ol...no difference.

i guess i'll have to borrow a gas tank and see if thats the problem...i'm thinking its something more serious.

my mechanical skills are about zero...i'm debating on just bringing it in somewhere and see what they say...but if it's something easy i'd rather just do it myself.

i forgot to mention this when this boat was stored out in the cold for 2 years it was never winterized...my friend who i bought it from used it one summer day and parked it and it sat just like that for 2 years....when i firsted pop the cover off the motor there was a mouse nest between the cover and motor.

the motor looks like showroom condition from what i can see...its probably been on the water 15 times...but thats just looks...like i said i have no mechanical skills and can barely find the things u guys talk about lol....i just found the fuel filter so i guess i could take a peek at that next time.

whats the worse case scenario here for it not being winterized and stored outside? knowing my luck its the worse case scenario and not something simple.

what about the gunk i found in the airlines? i couldn't even blow through them...could there still be a nest or something on the inside i can't see that causing problems?

i'm just tryin to get to the bottom of this...if worse comes to worse i guess i'll have to take it in and have someone look at it.

[FISHINGURU]

i forgot to mention that now if i go from idle and just straight pin it...it muffles out and dies most the time...sometimes it takes off really slow and boggy and slowly gains speed.

and after it kills when i try to idle it i have to put it on choke or "fast idle" on my boat...i can turn the key for days and it won't start but if i choke it, it starts right up everytime within a crank or two....if i keep it on "fast idle" it idles really nice...but when i go to take it off "fast idle" so i can shift into foward to go it sometimes kills before i can go from "fast idle" to foward.

[meatfish]

I had a problem a lot like what you are saying and by no means am I a mechanic.But after trial and error and most likely throwing some parts at it that it did not need I think what fixed it was#1 replace the air line you talked about and # 2 I turned the needles in and counted the rotations,backed them all the way out and blew the seats out with carb cleaner and replaced the needles.Runs like a champ now.Now the first thing I look at is that line.Cheepest part on the boat.

[boatfixer]

At this point, based on the history of the engine, I'd suggest cleaning the carburators.

[JohnMickish]

Rebuild the carbs in the spring and your problems will be over.