Mercury outboard wont run full throttle

Hi guys am seeking help with my 1997 Mercury 2stroke 99hp outboard it runs great in idle and reverse but as soon as you click into forward as you increase speed itll kick in but then start to decrease speed after about 10 seconds but sometimes will run fine for 10 minutes or so. The motor ran great and I ran full throttle for about 15 minutes from the launch to my slip.

When I started the motor she ran a little rough and when I left the dock the boat would not go at full throttle.

Mercury outboard wont run full throttle. Apr 23 2018. Ahoy all Our motor will not run out correctly above half throttle we believe the new style plastic floats may be to blame. The fuel pump is new all the hoses are new as well as one of the tanks.

We can get the motor to. Motor wont run at full throttle - Boggs down when full throttle. I have a 1990 75hp Mercury outboard engine on a 155 foot bumblebee bass boat.

When I first launch the motor always seems to run best. Outboard wont run full throttle unde load - Boating - Fishraider. Hi guys am seeking help with my 1997 Mercury 2stroke 99hp outboard it runs great in idle and reverse but as soon as you click into forward as you increase speed itll kick in but then start to decrease speed after about 10 seconds but sometimes will run fine for 10 minutes or so.

I launched my 2005 Montauk 170 with 90 Mercury yesterday. The motor ran great and I ran full throttle for about 15 minutes from the launch to my slip. Later in the day I went out again.

When I started the motor she ran a little rough and when I left the dock the boat would not go at full throttle. The engine bogged down. On my 1990 100 Mariner outboard it will run at full throttle of about 10 minutes then without cahangong the throttle it will slow down to a idle and continue running at an idle.

What can I do to corre. Mercury outboard won t run full throttle. I take throttle back to slow idle for 10 seconds go back to full throttle runs smooth for 5 seconds bogs down again.

Nov 05 2019 Lawrence recommends. Do not modify your engines. 0-liter displacement powerhead on the Mercury 150hp FourStroke is coupled up to a robust 4.

Bobs201 New Member. My 2003 2 stroke 150 merc runs fine at 12 throttle but dies out at full throttle after about 3 mins. It begins to sputter until I either ease off the throttle or it shits off.

It it hard to start after shutting off and cranks similar to trying to crank it with the kill switch off. I have changed the fuel filters had carbs. One possible reason why boats no longer achieve appropriate speeds at full throttle is a spun prop.

This occurs when the bond between the propshaft and blades are broken which subsequently causes the rubber insert to spin independently. 1999 200 efi mercury outboard motor starts and runs great except at full throttle it will die after couple minutes but then restart right away go to full throttle and repete. Mercury Tracker 40 hp 2 stroke 4 cylinder Changed out water pump now I have no reverse or neutral and it starts up in gear.

My 50 HP Mercury will only run at half throttle. I have replaced the powerpack coils and trigger but am still only getting half throttle. I tested the voltage on my powerpack and am getting 295 volts from the stator side and around 150 from the coil side.

The compression on all four cylinders is around 130 psi. 45 horse mercury outboard runs fine till warm then loses power at full throttle. Throttle is reduced and it starts to rev up then bogs down.

Outboard Boat Engine wont stay running - Adjust Idle Screw - VERY EASY - YouTube. 1976 75 HP Evinrude runs good but wont run full throttle. So if I understand it correctly to set the timing the plugs must be grounded or set to spark a gap.

The throttle should be set all the way up. Make sure the timer base is against the bump stop. Then use the light to see if it hits 4 degrees under factory spec.

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. My 2006 5 HP Mercury Outboard started easily and idled perfectly first trip this year.

Wouldnt rev to full power. Assumed Ethanol affected carb or small amout of gas left from previous year. Cleaned carb and replaced same problem.

Installed new carb same problem. Replaced exterior tank tank line wbulb filter and all interior gas lines. Fuel Line Air Leak.

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.

My 2002 Mercury 99 4 stroke outboard will only run 2k rpm full throttle idles very rough and dies idle oil - Answered by a verified Marine Mechanic. This is really an easy fix you can do yourself without having to pay a mechanic. HERE IS PART 2 of this Mercury outboard fix.

Finding the high pressure f. Mercury 50 1987 bogs down when full full throttle 13 posts Sep 12 2013 Motor Runs great bogs down under load. 1 - iboats.

Mercury outboard won t run full throttle.