2000 25 HP Mercury 2 Stroke Outboard, Tiller, Manual Start

[tryn2rtre]

I have a 2000 25 HP Mercury Outboard 2 stroke. I have put in a new carburetor kit, replaced the fuel tank, fuel hose, primer bulb, filter, fuel lines, primer diaphragm, motor fuel connection and fuel line fuel connection. I have gone from motor starting only, starting but dying when put in gear, running at WOT for 1 minute and dying with immediate restart to now starting, running at WOT or mid for 10 or 15 minute run, shutting down when I arrive at my spot. After 30 minutes of fishing, motor restarts on first pull, but dies when forward is engaged. I have to pull the cowling, slightly rev the motor a few times and then put in gear. Runs fine after that. Idle seems to be at the right RPM.

I suspect some minor adjustment, but I can't find a reference on the procedure and don't have a manual. Each repair noted above was in response to a specific problem ie.. fuel leak, no fuel, running problems etc. Bought this motor from a "Boat Mechanic" that said he went through everything. Also, not overheating and good water stream. Does not appear electrical.

 

[orbanp]

Here is an on-line factory service manual for Mercury motors.
Hope that helps.

EDIT:
Sorry, the system does not let to post the correct link, it overwrote it to its own web site.
Send a PM with your e-mail address and I will send the url!

Peter

 

[tryn2rtre]

Thanks Peter.

The manual is very helpful. Looks like I have just a little more work.

 

[tryn2rtre]

So I added the fast idle linkage and tested again. The motor dies when I put it in gear after the first run. I had to put it in forward, pull the primer button until the boat started moving and then push it back in. I am going to change to ethanol free gas and see if the symptoms change.

 

[undone]

E-0 will have no effect on this. you still have a fuel supply issue, not a fuel type issue. If you need to pull the primer knob out to make it run it means it's running too lean. Check for air leaks in the fuel line, weak fuel pump,, carb still dirty, etc.

 

[tryn2rtre]

It may still have some garbage in the carb. I replaced the full carb kit, but may need to run some wires through some of the ports. I'll get something to soak it in also. I pulled the plugs and they're not oily, so the lean part sounds correct. All of the fuel lines have been changed, the primer bulb and the connections. Fuel pump was rebuilt also.

Thanks for the tip.

 

[oldman570]

You can try using a can of Power Tune carb cleaner that can be bought at the local Merc dealer before tearing the carb off . It will do wonders at times, and can save work. Make sure that the idle jet screw is turned out 1 1/2 turns from lightly seated, and that the air vent jet on the carb is clean. Adjust the idle jet, after the motor has warmed up, so that it is set in the middle of the lean and rich missing of the motor. Best is to go a little to the rich side a blade with of a screwdriver. If the motor still dose not run good, use a piece of clear tubing in place of the gas line to the carb and check for air bubbles in the fuel supply indicating a air leak. Remove the clear tube and replace the standard fuel hose when done. JMO
Oldman570

 

[tryn2rtre]

Thanks for the advice. I ran it yesterday after taking it apart and inspecting everything and the stalling while engaging forward was no longer an issue. It did flood on me after the third stop, but getting it into gear was no longer a problem. I like the tip about the clear hose. That would help diagnosing air leaks. I did discover that the previous owner or "mechanic" gutted the thermostat. I have a new one on order. I figured that inconsistent head temperature may have an effect on setting carb. Orbanp had also made the same recommendation and provided a manual that has been very helpful.

Thanks.

Tryn2rtre