18 hp B&S dies after a few minutes

[kyle3194]

So I have an 18 hp B&S on my old Murray mower. I broke the plunger on the original carburetor so I went out and bought a used one from a guy on craigslist. It now starts up fairly well (took a lot of cleaning of the carb) however it now dies on me a lot. I can have it running in the garage in neutral at all different throttle levels for 10 minutes, but when i put it into gear and drive it out, it dies on me in 30 seconds or so. I talked to my uncle and he said it may be a problem with the coil. How would you guys go about working on this?

Thanks guys, your help is appreciated!

-Kyle

 

[Rivets]

Two things I would check first. First I would check to see that the fuel line from the tank to the carb is clear, don't forget to check. The inside of the tank. Last week I had a similar problem and found debris in the tank causing the problem. If everything is. Clear, I would that a second look at the carb. Is the float level correct and the float needle moving smoothly. Did you rebuild the carb or just clean it?

 

[Carscw]

When it dies on you will it start right back up or does it have to sit a few mins?

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[kyle3194]

Ya it usually starts right back up. It sat out last night in the snow and I tried to start it today, and it wouldn't stay running. It would turn over and just burn the carb cleaner that I put down it. Really becoming a pain now.

 

[Carscw]

Two things I would check first. First I would check to see that the fuel line from the tank to the carb is clear, don't forget to check. The inside of the tank. Last week I had a similar problem and found debris in the tank causing the problem. If everything is. Clear, I would that a second look at the carb. Is the float level correct and the float needle moving smoothly. Did you rebuild the carb or just clean it?

I would just do as he has said he knows what he is doing.

Sent from my iPhone using LMF

 

[DaveTN]

So I have an 18 hp B&S on my old Murray mower. I broke the plunger on the original carburetor so I went out and bought a used one from a guy on craigslist. It now starts up fairly well (took a lot of cleaning of the carb) however it now dies on me a lot. I can have it running in the garage in neutral at all different throttle levels for 10 minutes, but when i put it into gear and drive it out, it dies on me in 30 seconds or so. I talked to my uncle and he said it may be a problem with the coil. How would you guys go about working on this?

Thanks guys, your help is appreciated!

-Kyle

I've got a twin cylinder B&S 18hp on a Murry as well. It has gone through 3 coils in 3 years since a friend got tired of it and gave it to me. Now it is sitting in the bone yard. Engine runs strong but weak coils. I also had the fuel pump to go out. In your case it could be either one. I would check the fuel pump to see if it's delivering sufficient fuel. It may be giving enough under a "No Load" situation but when you "Load" it by engaging blades it doesn't have enough fuel to operate. Also check the fuel supply from tank to carb and make sure no trash or blockages. Then try the "Jug Test" where you get a fuel tank above the carburetor, then try the start, run, and load and see what it does. I use a small pushmower plastic tank temporarily for the test. Be careful with gas fumes ~~ ~~~~ ~~ inside as they can find an ignition source like a pilot light or fridge switch or something and cause an explosion. A neighbor up the road did just that. Fueled his rider inside and the water heater pilot ignited the fumes and burned the house to the ground!! Better safe outside.