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Thank you so much for your reply that is fantastic in advice and informationHi,
Are you running off of a remote tank?
You say "the valve is open in the tank". Do you mean the venting valve?
If you're running from a remote tank, try pumping the primer bulb as you drop into gear to see if you can keep it running that way. If so, you could be sucking in air through a crack in the fuel line or it might be a bad fuel pump.
Other things to check might be:
Make sure you're running an NGK BPR5ES Spark plug gapped to 0.035"
The carburetor might be gummed up. These are very simple carbs and pretty easy to clean although I don't know how much of a pain it is to take one off and put back on this particular outboard. I have very limited experience with the 5 horse motors.
A couple of little tricks though you could try:
Refer to the link below....
Make sure that the throttle stop screw (item #.7) hasn't backed out due to vibration (they do sometimes) and allowed the idle speed setting to drop too low. If you're not sure about the setting you can try it in 1-2 turns to see if that makes a difference.
Note: if the screw has backed out, you'll want to replace it with a new tension spring.
Remove the jet plug (item # 28) and shoot some carb cleaner in that passage. Give the cleaner time to work and, VERY IMPORTANT....evaporate!... ....before attempting to fire the engine.
That might take more than 1 or 2 tries and ALWAYS be patient to allow the cleaner time to evaporate prior to turning the engine. You don't want to hydro-lock the cylinder by being in a hurry.
Remove the idle mixture screw and spring and spray that passage with cleaner. You can do that at the same time you spray the jet passage.
When removing the mixture screw, it's a good idea to count how many turns so that you can put it back as before. If you lose track, it's not a big deal because you can screw it in CAREFULLY until it SLIGHTLY bottoms out and then back it up 1 1/2 to 2 turns. You may need to make minor adjustments to that setting for best starts and smoothest idle but it's easy to do. Just remember to adjust after the engine has warmed up.
Find the small, horizontal holes in the top of the carb body used to vent the carb bowl and give them a squirt of cleaner.
You might also try opening the float bowl drain screw (item# 6) a couple of turns and spraying cleaner in there through the drain hose (item 25) or nipple.
Close the drain screw while the bowl is full and let the cleaner sit an hour or two.
Then, open the drain to release the cleaner and refill the bowl with WD-40 and allow it to drain before closing the screw.
That's a "poor man's" carb job. It works but not always.
There are internal passages and jets that, if plugged, will require disassembly to properly clear.
Other things that come to mind that could cause this symptom are...
Poor fuel volatility/contaminated fuel.
Fuel tank pick-up tube damaged/screen clogged.
Fuel tank vent valve plugged. Try running with fuel cap loose or off.
Fuel line quick connector worn or not properly latched. (Often causes a leak but not always)
Incorrect valve clearance. Adjust valves.
I hope there's something here that helps.
Good luck.
Than you so much for your reply and fantastic information I will check all those suggestions,hnank you againHi,
Are you running off of a remote tank?
You say "the valve is open in the tank". Do you mean the venting valve?
If you're running from a remote tank, try pumping the primer bulb as you drop into gear to see if you can keep it running that way. If so, you could be sucking in air through a crack in the fuel line or it might be a bad fuel pump.
Other things to check might be:
Make sure you're running an NGK BPR5ES Spark plug gapped to 0.035"
The carburetor might be gummed up. These are very simple carbs and pretty easy to clean although I don't know how much of a pain it is to take one off and put back on this particular outboard. I have very limited experience with the 5 horse motors.
A couple of little tricks though you could try:
Refer to the link below....
Make sure that the throttle stop screw (item #.7) hasn't backed out due to vibration (they do sometimes) and allowed the idle speed setting to drop too low. If you're not sure about the setting you can try it in 1-2 turns to see if that makes a difference.
Note: if the screw has backed out, you'll want to replace it with a new tension spring.
Remove the jet plug (item # 28) and shoot some carb cleaner in that passage. Give the cleaner time to work and, VERY IMPORTANT....evaporate!... ....before attempting to fire the engine.
That might take more than 1 or 2 tries and ALWAYS be patient to allow the cleaner time to evaporate prior to turning the engine. You don't want to hydro-lock the cylinder by being in a hurry.
Remove the idle mixture screw and spring and spray that passage with cleaner. You can do that at the same time you spray the jet passage.
When removing the mixture screw, it's a good idea to count how many turns so that you can put it back as before. If you lose track, it's not a big deal because you can screw it in CAREFULLY until it SLIGHTLY bottoms out and then back it up 1 1/2 to 2 turns. You may need to make minor adjustments to that setting for best starts and smoothest idle but it's easy to do. Just remember to adjust after the engine has warmed up.
Find the small, horizontal holes in the top of the carb body used to vent the carb bowl and give them a squirt of cleaner.
You might also try opening the float bowl drain screw (item# 6) a couple of turns and spraying cleaner in there through the drain hose (item 25) or nipple.
Close the drain screw while the bowl is full and let the cleaner sit an hour or two.
Then, open the drain to release the cleaner and refill the bowl with WD-40 and allow it to drain before closing the screw.
That's a "poor man's" carb job. It works but not always.
There are internal passages and jets that, if plugged, will require disassembly to properly clear.
Other things that come to mind that could cause this symptom are...
Poor fuel volatility/contaminated fuel.
Fuel tank pick-up tube damaged/screen clogged.
Fuel tank vent valve plugged. Try running with fuel cap loose or off.
Fuel line quick connector worn or not properly latched. (Often causes a leak but not always)
Incorrect valve clearance. Adjust valves.
I hope there's something here that helps.
Good luck.
Thank you very much for your replyHow did it run for you last season ?-----Do you store it with fuel in the carburetor ?----Open carburetor slow speed mixture screw 1/8th turn at a time and test run.
