ing . It blows fuel out the top of the carb . ( that is where the overflow is ) The flaot and float valve are fairly new . Help ! Thanks , D
Sport & Outdoor – Others
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I have to same motor with the same problem. Its the injector, it gets gummed up from the ethenal in the fuel. within the carbourator there is a little pin that is stuck and then fuel spills right out the corburator. People will tell you its the diaphram but not the case. It needs a little tap on the side of carburator and will correct itself(likely).
How to Identify and Resolve Common Issues ?
We offer a diverse range of insights on identifying and resolving common problems in sports. Our sources encompass academic articles, blog posts, and personal essays shared by seasoned athletes. :
Clogged Fuel Injectors
Many Yamaha 115 4-stroke problems such as starting issues and misfires can come from clogged fuel injectors. Fuel injectors can become clogged due to carbon build-up that prevents a smooth distribution of fuel.
Loose fuel line connections, pinched or blocked fuel lines. It would be best to inspect all fuel lines for any bad connections, damage to the line, and leakage issues. Replacing a damaged fuel line is typically the best course, as repairing a damaged line naturally leads to further problems within a short period.
Common signs include reduced engine performance, black smoke coming from the exhaust, backfiring, overheating, or hard starting.
Debris such as fishing line, excessive seaweed, beer can rings, or nearly any other material can wrap around the propeller and its spindle. This increases the friction and causes the bog, preventing it from rotating to propel your boat through the water.
Boat Engine is Sputtering and Losing Power
You most likely have a filter problem or fouled plugs. That could be why your boat motor is losing power. Solution: Replace the in-line fuel filter.
Too much fuel in the air/fuel mixture can make your vehicle surge, sputter, or even stall. For example, if the carburetor is set way too rich, it will push enough gas through to the combustion chamber and flood the engine. Your engine power might lag if the engine is being flooded while you`re driving, as well.
To check fuel delivery, remove the fuel line where it enters the carburetor and use a length of rubber hose to direct the flow into bottle or similar container. Fuel should pulse out in strong spurts if your engine is equipped with a mechanical fuel pump (electric fuel pumps are more of a steady stream).
If the engine is low on power, it will bog down when you try to accelerate. This could be caused by a number of different issues, including low compression, a bad timing belt, sucking too much air, or even a head gasket leak.
The most common reason is that your air/fuel mixture is inefficient or dirty. If your air filter is clogged or has a lot of dirt. It could be bogging down the engine. Consider cleaning the air filter or replacing it with an air kit to see if the problem is resolved.
At wide-open throttle, the F115 propels the Dominator to 39 mph and gets 3.8 mpg.
“We recommend 87 octane for both our two- and four-stroke motors. We stress the importance of a good, name-brand gasoline.” Additionally, Grigsby says Yamaha recommends the regular use of fuel additives, such as conditioner, stabilizer, combustion-chamber cleaner and gas-line anti-freeze.
The refined engine is claimed to return a magical fuel efficiency of 129 kmpl.
Discover Relevant Questions and Answers for Your Specific Issue
the most relevant questions and answers related to your specific issue
I have a 1996 yamaha wave venture 1100….ran greatsat for 2 yrs..started but only ran for spray into carbs….drained fuel started and ran good. Started about month later and would only run as long as primed with starter fluids…checked fuel filter(ok)…fuel flow to fuel pump ok…output of fuel pump appears ok….but engine will only run as long as starter fluid/gas is sprayed into carbs. I don’t think it’s the carbs as it ran great a month ago…now it’s starving for gas flow….so it appears to be a fuel delivery problem…what would be the sequence of tests up to tearing into the carbs? is there a fuel filter inside the carbs? remember it fires off great when primed…until the fuel spray is consumed…
Check the on/off/reserve valve
I have a 99 yamaha f100 four stroke outboard. Problem I have is boat will acclereate fine get up on plane and after running for about a mob at wot will decell and only run around 4500 rpm. Then after coming back to idle will have a slight miss then run smooth and repeat every run. Changed the plugs and fuel filters alll oe yamaha has fresh oil timing belt is good any ideas will help or fuel psi spec. I am an ase master automotive tech so I know alot about engs. To me it feels like it’s running out of gas. Like the carb bows are full when I take off but then runs out after running wot. Any info will help
I have exactly the same problem with my Yamaha F100, have you got any solutions yet?
2005 4 stroke yamaha 150 550hrs. normally use every week but due to surgery not used for 10weeks. Just before I went down I changed internal fuel filter, and zincs in motor. finally put in sunday. motor started fine left dock hit the power and started to come up on plane then stuttered and died. changed the external fuel/water seperator pump up the primer and started up again. with in a minute died down again. limped back to dock checked fuel filter and plug wire connections. pumped up primer and left dock went right onto plane for maybe 150yds then coughed and died. I could pump up primer and it would run but then die out. the fuel filter at the front of the engine would run dry until I pumped it up again. If it were a car I would suspect a leak in a fuel line but I can’t find any sign of one.
before we launched I put 10 gallons of fresh fuel in and added another bottle of ethanol stabilizer (CRC brand)
what proceedure should I follow to isolate the problem? I am a fairly competent mechanic as far as cars and trucks go. I don’t really want to have to take it to a marine mechanic.
This is going to be the fuel pump is not pumping any fuel. The primer is acting as a fuel pump. When you prime it, it gives the engine enough fuel to run for a little bit. But as soon as the fuel runs out, the engine is dying. So this is going to be a bad fuel pump.
My 1977 Evinrude 140 HP outboard engine looses power when it hits @4,200 rpm’s and goes down to 3,500 then back up to 4,200 and then back down to 3,000 or about there. This would continue if I didn’t slow down to 3,000 on my own. It runs fine at @ 3,000 when I slow it down. I have changed all the fuel lines from the fuel tank to the carbs, removed, cleaned out the fuel tank, put new gas and added a can of SeaFoam. I replaced the water seperator filter and cleaned the fuel filter. I feel the fuel pump is operating OK. Any ideas about what could be causing my problem? Could it be a bad power pack or stator? Help!!
Hi, this is obviously a stator problem since you have cleaned the fuel filter..
Mar 12, 2010 – Could it be the check valve? I took it off and the flap appears to be working correctly. This well has been here a long time. Never given me any problems. I do have galvenized couplers on the discharge and intake sides. Old. Could these be leaking even though they show no sign of water? The discharge is able to hold 30 pounds easily overnight. I do not hear any vacuum in the intake when I take it off. Could the pipe to the well have a leak? I know I would have to insert a sleeve bnut I do not want to go through the hassle if I do not have to. I had put on a brand new pump from the hardware store that did the same thing so I think that would elliminate the pump as being the problem.
Mar 12, 2010 – I have a 3/4hp flotec convertible jet pump. It is able to hold 30lbs pressure on the discharge side as the primie easily for 24 hours. It is not able to pull water from the well whcih has been here for years. i disconnected it for the winter and rehooked it up. The galvanized couplers on the discharge and pump side are old but do not appear to be leakeing as I taped them well. The check valve seems to be functioning well as I took it off and the flap works correctly. The well is not pulling watrer. there does not appear to be a vacuum on the check vale when I losen it. could the check valve be bad? I am aware I might have to resleeve the well, but do not want to hassle with this if I do not have to. I want to eliminate everything else first. i put another brand new pump on it to see if it was that. That partiuclar pump which was the same thng did not work either.
Your well has gone dry it seems. It has happened to my before. At first the new pump I purchased that did not pump I took back for exchange and still no water. I finally gave in and called the well experts and I was told the well was dried up
Motor no longer seems to work – have already tried new batteries
If the motor is exposed to the elements, rain water may enter the casing and freeze up the motor shaft, brushes, and windings can short out. May need replacing.
2004 KAWASAKI KXF250
Try a new plug sometimes a plug will not fire under compression. also adj the valves