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Surging idle - to much air suspect

I have a Craftsman High wheel weed trimmer model #917773703 (Briggs engine)

Was sitting around for a while so I cleaned the carb, put it back on and it wouldn't start. Used a sprayer with gas to start an sustain it.
Gas lines are fine and free flow gas to the carb, not very much coming out the check on the bowl. Pulled off the bowl, float is free, little gas, not much.

Bought kit for it: Kit-Carb Overhaul [498260] - $10.16 at eReplacementParts.com

Installed today, still will not start, gas flow issue. Installed new needle and seat and seals all around. Kit came with more stuff but doesn't look like it all goes on this carb.
Started and sustained with sprayer but will die if I stop.

Not sure what to do now, any ideas?

Exploded carb diagram: http://c.searspartsdirect.com/lis_png/PLDM/P0301218-00002.png

~ED~

So I went out and messed with it again, now it works
Turns out I hadn't pressed the needle seat all that way down..

Moving on now. It starts, runs, and even cuts. Only issue is the surging, not a normal idle. Less noticeable when cutting.
There isn't a adjustment that I can see.

Just did a quick Google search. Going to check the air filter closer, looked clean but who knows. Not sure what else to check for unless I didn't clean the carb well enough.

~ED~

Took the filter and its housing off for direct access to carb. Still had the surging idle. So I assume its getting to much air. I placed my thumb over the hole to restrict air flow and it starts to idle a better. So I have a air leak?

It sounds like the idle circuit is dirty.

The carb uses different circuits at different stages of running.

Thats why it does not surge underload.

pugaltitude said:

It sounds like the idle circuit is dirty.

The carb uses different circuits at different stages of running.

Thats why it does not surge underload.

Click to expand...

I do not understand how I would go about fixing that. This carb is minimal. There is a spot where it looks like a adjust screw would go but it has a plug in there.
~ED~
Oh I see, dirty. So then I should pull that carb back apart and clean it again? I used some spray carb cleaner from the dollar store the last time.
The kit I bought came with two welch plugs, one smaller then the other. I seen where one of them might have went and might have been been able to get the older one out but I didn't replace it. Not sure what is under that plug.

humphrey1989 said:

I do not understand how I would go about fixing that. This carb is minimal. There is a spot where it looks like a adjust screw would go but it has a plug in there.
~ED~
Oh I see, dirty. So then I should pull that carb back apart and clean it again? I used some spray carb cleaner from the dollar store the last time.
The kit I bought came with two welch plugs, one smaller then the other. I seen where one of them might have went and might have been been able to get the older one out but I didn't replace it. Not sure what is under that plug.

Click to expand...

I wouldnt remove welch plug as too much hassle back in.

Usually an ultrasonic cleaner would help but a good spray with carb cleaner and a compressed air should do the trick.

Thanks. Will let you know how that turns out. Ive got the compressed air, need to get more carb cleaner and also one of those welder/torch tip cleaners so I can really dig in there.

~ED~

Google ultrasonic cleaner. Wow, thanks for bringing this to my attention.

humphrey1989 said:

The kit I bought came with two welch plugs, one smaller then the other. I seen where one of them might have went and might have been been able to get the older one out but I didn't replace it. Not sure what is under that plug.

Click to expand...

Anyone have some input on this?

So today I took it back apart and cleaned it. Used some small wire to dig around in the holes and carb cleaner for a good clean. Still has idle problem. I may try taking the carb off another one and using it on here, I just cleaned that one today and runs excellent.


~ED~
Well it is going to be the carb that is at fault cause its causing two different mowers to surge. I don't know what to do with this thing.