Briggs and Stratton 550E not starting

[dhes]

I took out the plug and pulled the engine over about 15 times. It only really splurted on the first pull and not much more came out after that. I then got the engine up and running again after a bit of effort with cleaning and changing plugs. It was not running smooth and still throwing out black smoke with fairly strong smell of fuel. After about 5 mins it then started running smooth for about 10 seconds and cut out. I checked the fuel tank which had emptied. After a fuel refill and cleaning/changing plugs I got it running again but still not running smooth. Some white gunk started coming out of the air port on the carb as shown in pic below. I assume this is water in the engine? (This mower has been sitting outside all winter).

Anyhow I have the mower draining oil at the moment. Do I need to take off the flywheel and clean the white gunk out of the air port. I have sprayed carb cleaner into it and left the mower on its side to drain over night.

 

[Rivets]

I wish you would have changed the oil before trying to run the engine. Because the oil in the engine was contaminated with fuel, you didn’t have a lot of protection. The engine was running rough because of the contaminated oil, it should clear up and run smooth after it gets fresh fuel and oil, but this may take 30 minutes. I see no reason to remove the flywheel and try to clean the white gunk. Wipe off what you see and run the unit. This to will need to work its way out of the system.

 

[dhes]

Ok I changed the oil and got fresh fuel. The engine took a bit of effort to get started and it ran it for about 7 - 8 mins before running out of fuel. I noticed when I was filling it that fuel was running out of the carb so Im guessing the float is stuck or not sealing correctly. Anyhow i refilled and it fired first time and ran for another 10 mins. The engine is still blowing black smoke but feels a bit smoother to pull start. The video below shows it running but not easy to see black smoke. After 40 seconds of the video you can hear where the engine starts running a bit smoother before running out of fuel. I'm thinking that too much fuel is going to the engine. Would this be a reason for black smoke and running rough?

 

[Rivets]

What you described means the float needle is not closing the seat, producing a rich mixture. Time to rebuild the carb with a new needle and seat. If you don’t have experience with carb rebuilding, this is not the carb you want to make your first attempt.

 

[dhes]

Honestly, I am happy to give it a go. This is my friends old mower and I only took it on to learn how these engines work. He has bought himself a new mower and the honda in our garage runs like new after 20 years. We are going to sell this on either as running or for spares/repairs. Any advice on how to rebuild the carb with needle and seat would be appreciated. I have time but not worth spending money on a new carb for something that will be sold for 100 euro or less

 

[Rivets]

The price for a new carb is less than $50.00 US. Might be you best bet.

 

[dhes]

The price for a new carb is less than $50.00 US. Might be you best bet.

If I was going to keep the mower it might be worst investing in a new carb. I will try clean the needle and if that doesnt work it will be sold for spares or repair. Appreciate your help all the same and learned a bit about small engines.

 

[dhes]

Rivets: What you described means the float needle is not closing the seat, producing a rich mixture.

This indeed was the problem. The pin holding in the float bowl was not sitting correctly in the clips allowing the float bowl to drop as shown in pics below. When I pushed the pin down into the clips it would work correctly but then when I take pressure off the pin the bowl would drop. Lucky enough I found a second hand carb locally so replaced the whole carb and mower now runs perfect.