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Pulling my freakinb hair out and I donbt have much to pull out

"New guy here, and I purchased

"New guy here, and I purchased a boat about 6 months ago. It's a beautiful aluminum v-hull with a 50 hp yamaha 2-stroke motor. The boat sat up for quite some time, as the previous owner was an elderly gentleman, and couldnt get out much. To make a long story short, I've searched the forums, and everything that I've tried still isn't working. I can start the motor no problem. I've ran a can or 2 of deep creep through the carbs, and with the cover off of the motor, it will run like a spotted ape!!!! When I put the cover back on the motor, and try to throttle up from idle, I can never get past a low rpm without it dying. The motor has low hours, it just won't run properly in the water. Any advice would be greatly appreciated!!!!!!
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"James, when you say it will r

"James, when you say it will run like a spotted ape with the cover off....is that (a)above idle (b) in the water (c)in gear ? If it runs fine in these 3 areas with the cover off, I would suspect a blocked air intake in the cowl. I have seen mud daubers and paper wasps totally block an intake and cause exactly what you describe. Have seen these same critters plug the exhaust ports and telltale water hole. Plus the nozzle on fire extinguishers.
If it dies above idle with the cover off, in gear in the water, then we have to look somewhere else. Engine type?"
 
"It runs like a spotted ape ab

"It runs like a spotted ape above idle, in the water, with the throttle wide opened. It pushes the boat seriously fast. I checked the cover, and there is no blockage. It's a 50 hp two-stroke Yamaha. (1994) Out of the water, I can actually throttle up all of the way, and it seemes like the motor is going to run fine, but when I get it in the water, i can't seem to get it out of nuetral without the motor dying, unless I use a little help from starting fluid, or deep creep.Once I get it past that point, it runs fine, until i get it back around idle, then the same thing all over again. I haven't attempted to take the carbs off and clean them yet (3 carbs tied together by one linkage) because I heard if you get them out of adjustment, you're opening up another can of worms......should I just spend the money, and take it to a boat motor mechanic?"
 
"I have same motor but 60 hp a

"I have same motor but 60 hp and had to do a cleaning job on the carbs for essentially the same reason. The carbs are simple to take off and you dont really have to do anything but get the gunk out of the tiny holes (jets). I recommend that you run a gallon of gas w/ Seafoam in it, you can get it at any auto parts store. It might clean them w/o having to take them off and apart. Have you tried to run the motor on the water w/ the cover off...to check for air starvation as indicated above? Eubie"
 
"James...When you start your e

"James...When you start your engine, the idle circuit handles everything until you throttle up to a certain point. To get you past that point without the engine stumbling, the carburetor accelerator pumps give the engine an extra shot of fuel that the idle circuit cannot provide. This shot of fuel is usually enough to get the engine past the idle circuit and into the high-speed circuit where plenty of fuel is sent to the cylinders. It would be my thought that a thorough carb cleaning and rebuilding would solve your problems with anything blocking the carb passages and I believe the rebuild kits contain what you need to rework the accelerator pumps. I am not a mechanic, so others with ideas please feel free to correct my assumption. After all, the idea is to get the boat back in the water.
happy.gif

Gary"
 
James your motor doesnt have a

James your motor doesnt have an accellerator pump it really sounds like the idle jets are to lean to get the engine from idle to intermediate and then to high speed...turn each idle screw out 1/4 of a turn and try the motor.
 
"We have had the same problems

"We have had the same problems with a 2006 Yamaha 50 2 stroke?
We have one that has not run correctly since it was out of the box. It has been sent back to the dealer 3 times and each time they say it's fine.
First, the boat pulls hard to the right since they hung it on a boat that I had had for 10 years ( always ran good)
The most important, It will not run past idle speed for at least 10-15 minutes after the first crank up. Now it has gotten worse, in that it will not go past idle at all. It kills when you try to accelerate.
I do not wany to take it back to the dealer for the same result will likely happen.
Any help would be appreciated.
I had a Yamaha 40 that ran like a top for 15 years. I would hate to have to switch brands due to this mishap."
 
If the motor runs properly wit

If the motor runs properly with the cover removed there can only be two possibilities...an exhaust leak(as mentioned previously) or an ignition lead shorting out against the cover.
 
"Just took back to the dealer&

"Just took back to the dealer(again) he says he has been seeing this problem with all sizes of engines. He thinks it may be related to ethanol in the gas that sits around for too long.
I only get to run the motor once a month if I'm lucky.
The mechanic seems to think it is just varnishing in the top end jets.
I try to run it with the flushing ears, but he seems to think this never open the "top end " jets

Here we go again.
Thank goodness the thing is still under warranty.
I may start playing golf............"
 
"All Japanese outboards, espec

"All Japanese outboards, especially the smaller engines, have very tiny low speed orifices. It does not take much to clog them.

I use the same files a dentist uses on root canals to clean out these orifices, and probably bore them out a little bigger than specs.

On other engines a welding tip cleaner usually works.

I agree with the other comments regarding the cover on, cover off effect. I would also add that the problem could be caused by low vacuum or a vacuum leak. The slight restriction in air intake with the cover in place could be enough to cause it to bog down.

"
 
"Brian, you have reached the u

"Brian, you have reached the ultimate scapegoat for mechanics now..."It's gotta be ethanol!!". I fought this very same battle of engine performance for a year and they truely love that excuse. I was to the point that the carbs were being rebuilt almost monthly on an engine that was used 2-3 days a week and no fuel ever left in the tank/carbs/lines while parked. All fuel I use is treated with Startron and Ring-Free.They tell us that on the newer engines, ethanol is causing varnish, sludge, phase-separation to make the engines stop/run poorly but on older engines, they run poorly because ethanol is DISSOLVING all the old gum, sludge, and varnish. So, after having the carbs rebuilt the last time and they only lasted about 30 minutes, they got away from that excuse. Good luck to you on getting the engine right, keep us updated.
Gary"
 
Got the motor back in less tha

Got the motor back in less than 4 hours from the mechanic shop ( I WAS SHOCKED) He blamed the ethanol and recommended a new marine STABIL for ethanol. I guess he a did a quick carb job and gave us a call. I picked it up yesterday and went straight to the lake. I'll be darned if the thing didn't run fine!!
He said he has been seeing this problem more and more and does blame the ethanol.
I asked what i could do and the answer is "run it more often". The washout ears do not help according to him. He says it needs to have a strain put on it to help flush the carbs.
Thats it for now........Happy Thanksgiving.
I guess I will buy a manual and learn to do the carb cleaning myself. We'll see
 
"When you shut the motor down

"When you shut the motor down at the end of the day, do you pull the fuel line and let it run out of fuel or do you shut it down with the ignition key???"
 
"Hi guys,
I would like to kno


"Hi guys,
I would like to know if it's better to just pull the fuel line and let her run out of fuel or turn her off at the key if you are going to let her sit for a while?"
 
"If you have a single carb, yo

"If you have a single carb, you can let it run out of fuel, but if you have two or more carbs, it is better to drain the carbs if you want to remove the fuel from the system. I would do this if the engine is going to be idle for a length of time, not every time I turn it off."
 
"draining a carb is 10X better

"draining a carb is 10X better then running it, because it will never fully empty running it"
 
"Drain the carbies by removing

"Drain the carbies by removing the screw on the side of each carby, removing the fuel line will cause other problems down the track as the oil pump will continue to pump oil into the crankcase case."
 
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