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40 hp evinrude runs briefly

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bunky1940

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My 40 hp Evinrude runs in idle position for about 10-15 seconds and quits. Its easy to start and runs very well, but stops suddenly. If I am able to shift into gear, it will run for 10-15 seconds and quit.I have had the carburetors overhauled and new gas lines
 
kimcrwbr1 said:
Have you adjusted the idle mixture needle? Turn it in clockwise to lightly seated and then out 1 1/2 counterclockwise. Choke it and start it and let off the choke then feather the choke usually a few times until it idles on its own at high idle. You are mixing 50:1 oil mix correct. When posting give as much info as possible, model number, when it started acting up and what have you done. Your really brief on your description of the issue.
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Let me begin with the engine is Evinrude 40hp model # E40ELC. When I purchased the boat I had it in the shop for tune up and carburetor adjustment. It ran great when I got it back. After running it for several weeks it would not accelerate, only at lower speeds.
I have replaced the gas with non ethanol gas added Stabil (sp) and carburetor additive.
As current, with your previous suggestions the motor will start and run for 10-20 seconds and stall. I have discovered that when it begins to stall to push in the choke switch and it will rev up, but will not continue to run. I believe it has the electric primer system.
Thank you for your assistance.
 
Depending on the validity of your description, it clearly is running out of fuel. Next question is why. You say that squeezing the primer bulb doesn't help, so the fuel pump probably is not the problem. So.......it looks like it's back to see what was done incorrectly with the carburetor. But if it were me, I would first verify the fuel delivery to the carburetor by temporarily teeing a fuel pump pressure gauge in between the pump and carburetor. Reckon I believe in diagnosing before fixing.
 
Thank you for all your help, but I'm afraid that what I said may have been misleading. When it begins to stall I push in the choke and it revs up again. As long as I continue to choke the engine, it will continue to run. As soon as I stop choking it, it will stall. It always starts very easy and runs well on the gas it has, but when it begins to stall, I need to choke it over and over.
 
The electric primer which is fed from the fuel pump ,by-passes the carburetors.---------This clearly points to a problem with the carburetors / adjustment of them.
 
racerone said:
The electric primer which is fed from the fuel pump ,by-passes the carburetors.---------This clearly points to a problem with the carburetors / adjustment of them.
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Thank you very much for all the good advice. I will adjust the carbs like you said. If problem exists, back to the shop or any suggestions about tackling the problem myself?
 
Where this motor has two carbs, I find it interesting that you have to keep choking it to get it to run at all. You say it ran fine for a few weeks and then no power, only at low speed or now idle. If it ran well for a while the carbs were adjusted correctly unless the boat is now at a different altitude then when it ran well. I think your fuel delivery is bad. Pump up the ball until it is hard then unhook the fuel line from the tank. Next undo the drain screws from the bottom of the carb and see how much fuel comes out. If it very little you are not filling the carbs, float issues. If there is a lot of gas then your main jets in the carb are plugged up and they need to be disasembled and re-cleaned. This is all based on the information you have provided.
 
thebubba said:
Where this motor has two carbs, I find it interesting that you have to keep choking it to get it to run at all. You say it ran fine for a few weeks and then no power, only at low speed or now idle. If it ran well for a while the carbs were adjusted correctly unless the boat is now at a different altitude then when it ran well. I think your fuel delivery is bad. Pump up the ball until it is hard then unhook the fuel line from the tank. Next undo the drain screws from the bottom of the carb and see how much fuel comes out. If it very little you are not filling the carbs, float issues. If there is a lot of gas then your main jets in the carb are plugged up and they need to be disasembled and re-cleaned. This is all based on the information you have provided.
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I appreciate all your assistance.
 
kimcrwbr1 said:
http://www.marineengine.com/parts/j...LCRM&manufacturer=Evinrude&section=Carburetor
Do you have to prime it to get it to fire? Put a small dish under the carb and remove the high speed jet #19 you may need to grind a wide screwdriver narrow to fit the high speed jet good so not to damage it. It is possible the jet is clogged clean the jet with a soft copper wire and get a can of seafoam spray. Pull the low speed orifice top center of the carb and blast it good with seafoam. Also clean it with a copper wire. Put it back together and fill the carb with seafoam and plug the fuel ine back in. Start the engine and just keep pushing the primer at high idle and see if it will run on its own. Do you run the engine out of fuel after each use?
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I removed the #19 jet and fuel came out of both carbs. Also I could not get a firm primer bulb. After squeezing it several times I notice fuel leaking out of the #1 carb. The fuel line to it wasn't leaking, but the entire carburetor was wet. All other lines were dry. I had these overhaul just 3 months ago.
 
It is possible that the float on that carb is not set correctly and does not shut off. Sometimes if you squeeze hard you can overflow a carb even with it set correctly. Sounds like carb issues to me, specifically float adjustment as I suspected. Could even be just a small piece of something caught in the float preventing it from shutting off.
 
modderman said:
Is the fuel pump working fine? did they do it well?
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Well, I'm back. I have done all that you recommended, put new kits in the carbs, new supply line from the gas tank and check all adjustments.
My main issue now is that the motor which is an Evinrude e40elcud, 1987 with a VRO fuel pump. The oil line is disconnected and I mix the gas 50:1 2 cycle oil.
The motor starts very easy and will idle without shutting down. I can put in forward and the motor will perform excellently for about 10-15 minutes and then will lose power down to a slow, medium thrust. It will eventually die unless I pump the primer bulb to keep it running, however it will not get back up to a faster running speed.
Could it be the VRO fuel pump? Thanks
 
kimcrwbr1 said:
It does sound like a restriction somewhere or a bad fuel pump. Is the primer bulb partially collapsed when it starts to falter? You can allways just add a fuel pump for a lawnmower motor and see if it cures the problem. Is the pulse hose on the motor in good condition and tight on both ends?
http://www.ebay.com/itm/FUEL-PUMP-f...692?pt=LH_DefaultDomain_0&hash=item2c73e5813c
You can get one at any lawn mower shop. A faulty vent cap on the tank or a restriction in the puckup tube strainer could also be the problem. To verify either loosen the cap or take the fuel line off of the fitting at the fuel tank and just stick it down into the fuel. If that cures the problem the tank needs serviced or replaced.
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Yes, I did notice that the primer bulb was collapsed, but not completely. When I pressed the bulb , it seems to help. I don't know where the pulse hose is on the motor. It has a VRO pump. Could I change the VRO pump to a regular pump on earlier models? I mix the gas now and don't need the VRO. If so, can I get directions on how to install?
Thanks for your help.
 
A simple pump that bolts directly to a pulse hole on the side of the top cylinder is available.----Look on this site for the simple pump.--It is found on the 48 HP model and on commercial models.-------If the bulb collapses then that points at a restriction in fuel flow from the tank or hose downstream of the bulb.
 
bunky1940 said:
Let me begin with the engine is Evinrude 40hp model # E40ELC. When I purchased the boat I had it in the shop for tune up and carburetor adjustment. It ran great when I got it back. After running it for several weeks it would not accelerate, only at lower speeds.
I have replaced the gas with non ethanol gas added Stabil (sp) and carburetor additive.
As current, with your previous suggestions the motor will start and run for 10-20 seconds and stall. I have discovered that when it begins to stall to push in the choke switch and it will rev up, but will not continue to run. I believe it has the electric primer system.
Thank you for your assistance.
Click to expand...
bunky1940 said:
My 40 hp Evinrude runs in idle position for about 10-15 seconds and quits. Its easy to start and runs very well, but stops suddenly. If I am able to shift into gear, it will run for 10-15 seconds and quit.I have had the carburetors overhauled and new gas lines
Click to expand...
Try this-
Remove the air chamber from in front of the carbs. (It’s not difficult).
The carb bowls have a drain screw at the forward bottom. Remove those and drain the old fuel. Remove the bottom carb (it’s not difficult). Remove the bowl and you’ll see a tiny port behind the drain screw hole. That is probably plugged with corrosion and crud. Poke a thin wire all the way thru that port. You can see when you’re thru.
Reassemble and reinstall the carb.
Clean the port on the top carb without removing it. Now that you know where the port is, you can do it by feel.
Put it all back together, and I’m betting she purrs like a kitten.
Next time, don’t let it sit over winter with old fuel in it.-🙂
 
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