Outboard motor not running at full power

Outboard motor runs but wont plane. If everything has checked out so far then it is the engine side fuel system.

It is bad for the motor running it at high rpms without a load because it takes alot less fuel to run faster.

Outboard motor not running at full power. Another possible reason your outboard motor is struggling to reach full speed is an air leak in your boats fuel line. In case this happens there will be a constant fluctuation in the fuel supply pumped into your boats carburetors. As a result you will experience your outboard motors RPM fluctuating up and down.

It is bad for the motor running it at high rpms without a load because it takes alot less fuel to run faster. Engine oil is in the fuel so revving it up without a load is like running your car after draining the oil out. Besides running the prop fast out of the water can damage it also.

Another possible cause is an air leak in the fuel line. When this occurs theres a constant fluctuation in the amount of fuel thats pumped to the boats carburetors and as a result the motors RPMs go up and down. Regardless of your boats throttle setting the presence of an air leak will greatly restrict its speed.

Hi Tan its a 2 stroke motor. Ive replaced the sparkplugs but while running if i remove sparkplug wire leading to no. 2 it still sounds the same as before.

Also i have taken off the air filter cover to check whether all three carbs produce the same amount of fuel but no2 only does about half compared to 1 3. First you want to run a boat side fuel system test. It is a bit elaborate so I made the procedure a PDF document.

Testing the fuel pump is in this test also. Boat side fuel system test – click here. The test again is passfail.

If it passes we move on to carbs. If everything has checked out so far then it is the engine side fuel system. Once I put it in gear and plane out the boat the motor does not rev up to full throttle.

I have the trottle arm all the way down and it seems to lack power. Every now and then the motor will instantly red to full throttle but then back down again a second later. New plugs are in the motor.

New gas coming from a clean Jerry can. Loosing power at full throttle Remove lower unit—-Inspect waterpump—–Look UP INTO EXHAUST housing and look for blockage in exhaust. Quick Navigation Mercury Mariner Outboard Forum Top.

Johnson outboard looses power while at speed. When this happens check the primer bulb. Does it go flat.

If so then you have a problem upstream of the motor. Clogged tank vent clogged pickup screen fuel filter fuel line ect. To eliminate the vent you can crack open the filler cap while running and see if that helps.

Outboard wont run full throttle unde load. Why you will see 10 different posts from 10 different people of what the fault isI would not be mucking around with a outboard engine if you cant do or do not understand the basics in mechanics or electricalIf you dont know how to pack bearingsuse a multi meter or cant change an impeller I. Check that the air vent on your fuel tank is open and not blocked that there are no air leaks in your tank-to-motor hose and that your fuel pump is in good shape.

Another possibility is overheat Check out your cooling. 30hp model AE loses power at 34 to full throttle. It seems to be a fuel issue.

When it starts to lose power I can squeeze the bulb once to keep it running for another 30 seconds or so until it starts running weak again. Squeeze bulb and it improves. Cheap fuel lines hose clamps and connectors commonly cause problems with your outboard engine.

First squeeze the ball as you watch the fitting between the engine and the line the barb and the hose the barb on either end of the ball and if its visible the fitting between the line and the tank. With my 70hp my boat will top out at 30mph and now i put the throttle down and it goes 9mph wide open. I can get it to 28 to 35 mph trolling speed and it runs a little rough while trolling and if i go any slower it will stall and while trolling i have to hit the choke every 15min or it will stall or as it feels like its gonna stall i throttle up a hair.

Outboard motor runs but wont plane. Steilacoom WA 2003 Trophy 2302 with 200 HP EFI Mercury saltwater outboard – running along today at 32 mph on Puget Sound when boat suddenly lost power kept running no engine alarm noises – now the boat continues to run but wont plane – anyone have any ideas on what could have gone. Outboard Motor Not Running At Full Power About Outboard Motor Not Running At Full Power If you are looking for Outboard Motor Not Running At Full Power.

Check to make sure that the shifter is not in forward or reverse. If the engine turns over or cranks like it always has then chances are you are looking at a fuel problem. Always start troubleshooting with the simplest items first.

Check the fuel system step by step from the tank to the motor. If your outboard engine is sputtering at any speed idle or full throttle it could be the result of several common malfunctions. You may need to make a few timing adjustments or replace a spark plug or you may need serious mechanical inquiry.

Basic troubleshooting for YAMAHA outboard motors part I A problem in the fuel compression or ignition systems can cause poor starting loss of power or other problems. This basic troubleshooting and possible remedies and covers all Yamaha outboard motors. Therefore some items may not apply to your model.

10-26-2014 0848 AM. Dt140 91 running issues. The heavier gas smell in enclosed areas may be related to evaporation of gas from multiple carbs.

And Or could be the gas spilled down inside Cowling from working on the motor. And if floats in carbs are set too high gas may sit in throats of carbs. This spark then ignites the fuel which keeps your motor running.

Symptoms of a Bad Coil on an Outboard Motor. If your coil does go bad there are several symptoms you might notice. Engine Experiences a Hard Starting Condition.

When the coil becomes weakened and damaged it is unable to produce the energy that it once did.