Need a some help on this one.

Situation

1) Prime carb, enguine starts, after about three seconds or so, dies. Will not continue to run.

What I have done.

1) Check spark, all good. Even when the engine dies after start-up, still strong spark. We will rule out the spark for sure.
2) Taken carb off and cleaned multiple times. I have been into every small hole and cleaned this out top to bottom. It is a plastic carb with a main jet.
3) Fuel gets into bowl fine.
4) Filter over main jet has been cleaned. There is no issue there as priming sends fuel up the carb
5) I have reset the float. It was a little low. Reset to parellel to carb.
6) I cleaned out the exhaust. Dont think it is that as it start and runs.

I can keep it running by hitting the primer. It is the only way.

It feels like the engine is not sucking like a vaccuum the fuel up to the carb intake as it is running. I do not understand this???? Is there anything I can try to prove this?

I have had the carb off 5 times. I did not buy a rebuild kit. Do not really want to to be honest.

Is there anything else I can try on this. The engine did not start as well when I had the filter and the filter cap off. Only when i put the filter back in and lid, then primed it, would it fire up. I found that strange as I have never encountered that on a 4 stroke.

I am at wits end with the two stroke and could really use some advice. I love the way it runs when it does go and beleive there is value in keeping it gonig. It is a nice mower.

Lanwboy gold series 5hp 2 stroke.

Craig

 

Post the model number for the mower so we know what engine it has, you have a fuel restriction somewhere or an air leak, you can check for the air leak by spraying carb/brake parts cleaner behind the carb and along the crankcase mating surfaces while it is running, if the engine tempo changes you have found the leak. Have a good one. Geo

 

Hi Geogrubb,

The model number is 10422.

I am going to have a hard time finding an airleak when I can barely keep it running.

Not much room inder there it spray carb lceaner anywhere to find an air leak.

I am sure it is an airleak now that you mention it.

What if I choke the carb right off where the air filter is to give me more vacuum,

Would thi ultimately prove that there was a leak somewhere?

Like I said, it would not even start at priminig until i put the filter back in and put the cover back on. I found that strange to begin with.

If I hav an airleak somewhere, would it mean i just need to tighten up some bolts on the engine. Probably a dumb question if I do not even know where the air leak is yet.

Thank you for your help.

Craig

 

If it runs choked, it only proves that it isn't getting enough gas, which we already know. Still sounds like a carb problem to me... might need to put some new parts in the carb... this carb is plastic, right?

 

Cheese,

Yes, the carburetor is plastic. I have cleaned every orifice of this carburetor. I have used a piece of wire in and out of all holes to clean it out. Carb cleaner followed. There is no blockage. The jet was also cleaned. There are two small holes each side of themain jet. I have cleaned them out as well. When I take the bowl apart, there is plenty of gas.

As I said previous. When I primed the carb, and had the air fliter and cover off, the mower would not start. When I add the filter and cover, prime, it starts fine.

Ther eis no choke on this carburetor. I will add a diagram of the carb.

tonight I will be taking it apart again. I will be pulling the flywhell off etc to see if anything is loose like bolts etc. The gaskets seem fine on the carb as well.

Please see attached link of the carb.

www.partsandservice.com/bin/ipl.cgi"]
www.partsandservice.com/bin/ipl.cgi[/URL]

Thank you for looking.

Craig

 

Maybe time for seals on the crankshaft???? If they leak around there you'll never get them to run right,,,,
Roger

 

Hi Everyone,

I got it running. What I did was put a small piece of cardboard in front of the air filter in front of the carb in effect choking it off. Primed it, and boom she continued running. I let it run for a minute or two. I then removed the cardboard, primed, gave her a pull and it ran.

It doesnt seem as though she run perfectly but she is running. Seems like a little bit too much smoke but not as much as start up. Might be normal for a two stroke.

I will leave her overnight and see how she starts tomorrow.

I dont toally understand why she is running now outside of the fact by putting ther piece of carboard over the carb and choking it off, there would be more vacuum and this pulling fuel up from the bowl into the engine.

She still always starts after a prime.

Is it possible that it just needed the extra vaccuum in order to finally get gas flow.

Not quite sure, seems strange.

I will send another update tomorrow after a cold start.

I really do apprecaite the replies. I am learning a tonne and I guess at the end of the day it is really what it is all about.

Just trying to do my piece to keep them out of landfills.

Craig

 

Hopkins,

I have one question. Where do I find the seals for the crankshaft. Would that be under the flywheel. Might be a dumb question but is the crankshaft what the pill cord/flywheel goes over to start the motor. Would I have to open the engine to replace this seal?
Can I look to see if it is leaking somewhere?

I have always been concentrating on the carb but want to be sure I do not have an air leak somewhere.
Craig

 

While I am not familiar with your model I have experienced clogged mufflers causing the same symptoms - starting, then quitting. The ones I've experienced this with are blowers and string trimmers which are smaller. Both experiences came with engines that had spark arrestors in the muffler that had clogged. Anyway, it might be something to check out.

 

The crankshaft is the part that the flywheel is bolted to on top & the blade on bottom. You do need to remove the flywheel & blade & muffler to get to them. If you see any sign of oil around them, air & fuel is leaking out & just air gets drawn in & leans the mixture out.. Roger

 

Hopkins,
Thank you for the information, it is helpful to understand.

I have the mower running. I prime it, start it, runs for 3 seconds, dies, i do this about 6 times and then she runs fine. Just feels like when she is cold, it takes about 6 or seven starts and stops to finally keep it going. In other works, once it is warmed up, all is running not so bad.

I do not see any oil aroujnd the crankshaft.