# Mercury 50HP 2stroke tiller bogging down



## cutrunner (Jun 8, 2010)

Carbs are gunked. It runs great for that first 30sec until the jet sucks the crap off the bottom of the bowl.
I would have the carbs cleaned and an anual service done


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## mark_gardner (Mar 18, 2009)

agree with cutrunner


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## JRP (Sep 24, 2012)

definitely sounds like an ethanol related problem from sitting.Try this it has worked for me on outboards ,chain saws, four wheelers ect. First get all the gas out of your tank if not removable you can use a small elec fuel pump being careful of any spark near tank long hoses and leads.Drain carbs via hex heads on side of carbs.Blow out fuel lines be sure they are ethanol rated ones not the old gray ones which deteriorate .Put new filter on engine and screw on with the high micron filter.Buy a few gallons of Rec fuel and put in sea foam the highest mixture allowable.Run engine,let sit, run engine, let sit be patient with it.On a chain saw it took a week at first needing stating fluid to get it putting.This should work in the event the carbs are just to gummed up they will need an overhaul try this first.I now run only Rec fuel in everything not only does everything run so much better it can sit for periods without the problems associated with the ethanol crap. Hope it works out for you.


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## danville_marine (Jan 24, 2013)

ckeck your hose maybe coming apart I worked on a pontoon run great at 2500 rpm wot would run good for about 100 yards hundred pretty much quit pump bulb good to go pulled hose off took bulb off tried blowing though hose collapsed inside no signs out side


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## Dudeitsmattx (Nov 3, 2013)

So good info guys thanks. I've been told to try and use non ethanol or if I do use the normal gas to put stable in with it so the gas does not get bad


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## Dudeitsmattx (Nov 3, 2013)

After installing new spark plugs, fuel filter and fuel water separater I can't get her to turn over. I can pump the ball like 50 times and it does not get hard. Any reason why? Obviously the fuel is not getting sucked into the fws then back out into the line to run the motor


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## cutrunner (Jun 8, 2010)

Bad fuel pump, your just filling the crankcase with fuel if you pump it like 60 times. Be careful, you can hydrolock it like that and bend some rods


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## Dudeitsmattx (Nov 3, 2013)

It just does not seem like any fuel is getting pumped in it. But I'm going to leave it alone and take it to a shop and have them fix it and finish up the 1 year service


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## Creek Runner (Sep 1, 2011)

Is your primer bulb before or after the FWS? Sounds like maybe an air leak your sucking air into the ball not creating a vacuum to pull the fuel.

Did you fill your FWS up with fuel? You should always fill up the canister with fuel before installation, then prime your bulb and fire up the engine, squeeze the bulb and hold it half squeezed until you feel fuel running through it. 

When you say it won't turn over, that means that the engine will not turn over (not start, 2 different things) not starting means that the engines turns over but will not crank, not turning over would indicate a problem with the starter, battery, etc etc. or it's locked up. I think you mean it won't start, not (not turn over). Correct me if I'm wrong. 

Move primer bulb after FWS, check for air leaks, check to make sure gas is in the tank, fill up your fuel canister with fuel screw on and prime the bulb, once you get fuel flowing through it to the carbs fire up the engine, hold bulb half squeezed while engine is running, the fuel pump will do the rest of the work and prime the system. 

Ps don't think the fuel lines was your original problem, I'm with Cut probably needed a carb job. 

Creek


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## Dudeitsmattx (Nov 3, 2013)

Ok no I did not put fuel in the FWS when I installed the new one :-/. I was going to but I was not 100% sure if I should have or not. And yes the bulb is after the FWS its in the back by the motor. And sorry I was wrong on my turn over wording. The motor cranked right up the first time I started it then shut off. I assume it just used what fuel was left in the bowl. So then I pumped the bulb and never got it to start and run after a few tries. I then stopped and did not was to mess anything up. This is what I get for working on a boat for the first time ever lol


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## Dudeitsmattx (Nov 3, 2013)

> Ps don't think the fuel lines was your original problem, I'm with Cut probably needed a carb job.
> 
> Creek


Yeah I don't think so also. The old FWS was full of gas it was all over lol. And the main line that runs from my gas tank to the FWS is a thick black rubber line while the line that runs from the outlet on the FWS to the bulb then motor is the small gray.

Whats the trick to not get gas all over when switching the FWS?


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## JRP (Sep 24, 2012)

If that small gray hose is the old non eth rated hose its probably deteriorated and your carbs are gummed up if so replace hose and try and do as suggested above with sea foam if that don't work you will need a carb overhaul.


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## cutrunner (Jun 8, 2010)

> If that small gray hose is the old non eth rated hose its probably deteriorated and your carbs are gummed up if so replace  hose and try and do as suggested above with sea foam if that don't work you will need a carb overhaul.


I mostly agree, but if the gray fuel line did deteriorate then no amount of seafom on earth will clean those carbs.

For changing fws I use one of those 1quart mixing cups and cradle the filter with that as I loosen it, and make sure to have the new one ready, also put a small film of grease on the o ring of the fws and it will come off by hand just incase of an emergency on the water


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## Creek Runner (Sep 1, 2011)

> > Ps don't think the fuel lines was your original problem, I'm with Cut probably needed a carb job.
> >
> > Creek
> 
> ...


Haha, a lot of rags  ! What I do is pinch of the inlet line going to the FWS, disconnect the primer bulb on the engine side and using the primer bulb pump the gas in the lines and FWS into a clear jug. I'm doing 2 things 1) checking for fuel contaminants and water, 2) Pulling the fuel out of the FWS so when I remove it gas doesn't spill everywhere. I then dump the rest of the gas in the FWS into the jug looking for contaminants as well. 

Please do not continue to run your engine with out a crab cleaning, and do not run a mechanic in a bottle (sea Foam) through your engine. If that engine sat up for a year it needs to have the crabs gone through *PERIOD*!  

Creek


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## Creek Runner (Sep 1, 2011)

> > If that small gray hose is the old non eth rated hose its probably deteriorated and your carbs are gummed up if so replace  hose and try and do as suggested above with sea foam if that don't work you will need a carb overhaul.
> 
> 
> I mostly agree, but if the gray fuel line did deteriorate then no amount of seafom on earth will clean those carbs.
> ...


Errr Cut beat me to it!  [smiley=1-boxing1.gif]   ;D


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## cutrunner (Jun 8, 2010)

Squirrel finds a nut every once in a while


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## Dudeitsmattx (Nov 3, 2013)

Yea I was not planing on using sea foam. I'm just going to take it to a local shop to have them clean the carbs and get the fuel in the FWS and get the motor running right.


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## cutrunner (Jun 8, 2010)

Good call


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## Dudeitsmattx (Nov 3, 2013)

So today I decided to get the fuel in the FWS and to the motor before I take it in. I watched a video on YouTube how to do that. By removing the line from the bulb to the motor. Then squeeze the bulb then place a finger over the hole and release the bulb then remove your finger and keep doing that until the fuel is to the bulb. Well sure enough it worked. Once the gas got to the bulb I drained it into a glass jar. And what do you know it is all nasty with water and chunks. So I contunuied to pump the fuel into a jar until all the junk stopped coming out. I took a few pics. 

Now I try and start it. Well it would start up then as soon as I release the key it would shut down. Did this a few times then it would not start at all. Just kept trying to start but would not. Checked the bulb and it's nice and stiff so I know the gas is flowing. 

Now my question is... Is my motor done since I've been taking it out with the fuel like that? I know the carbs still need to be cleaned but what about the rest of the motor? The date on the old FWS was 2008! Ugggh
That's is first jar bunch came out. 


This is the 2nd only a little came out on like the first or 2nd pump then it was clear.


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## Dillusion (May 21, 2012)

You're going to need to rebuild the fuel pump too.

I just rebuilt one in a 99 merc like yours and there is a little pocket towards the bottom where sediment gets trapped.

I would also put In a New fuel filter, the white one before the carbs.


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## cutrunner (Jun 8, 2010)

> You're going to need to rebuild the fuel pump too.
> 
> I just rebuilt one in a 99 merc like yours and there is a little pocket towards the bottom where sediment gets trapped.
> 
> I would also put In a New fuel filter, the white one before the carbs.


And clean the carbs
Bam!


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## Dudeitsmattx (Nov 3, 2013)

Hopefully that's all. I figured it would not stay running because all of that junk is trapped in there. She will be getting dropped off tomorrow. I just wanted to get the fuel in the filer and line so it's 1 less thing they would have to do. Not they just need to do the lower unit oil, water pump kit, thermostat and get the carbs and stuff cleaned out. And hopefully she will run like new again.


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## steve77777 (Nov 12, 2013)

I had this problem on my 90 merc,i took it in to bass pro ,they said they fixed it and it did the same exact thing,they had to meet me on the water,i ran it to 45 mph then it just started dropping rpms,they finally figured it out that when going fast it was able to suck something that was in the hose up to the carb and block gas from getting there......only did it when going fast because i guess when IT PRODUCED produced that much suction is when it was able to suck the particle to the carb to block the fuel....then if i stopped and started again it ran great again until i went fast again,....the particle would be floating in the line, i think when they did my carb stuff originally they had got something in that fuel line but i wasnt sure.. hope this may help


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## Dudeitsmattx (Nov 3, 2013)

Hmm well I took it to the shop. They said they were going to clean the carbs, do the 1 year service, and be sure to clean out all of the lines in the motor so they are clear of that build up. And also check my gas tank to see if its sitting in the bottom of the tank.


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## Dudeitsmattx (Nov 3, 2013)

Well I picked the boat up yesterday. Took it home and put the hose on the motor and boom very first turn of the key started right up! Man was that a great feeling. It has never started on the first turn. Sounded great, less smoke was coming out, also seemed like they turned the idle up because before it seemed like it wanted to stall out. I'm a happy camper now


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