# Help with the choke and throttle settings?



## Pilot1226

Hey everyone,

I recently picked up a snowblower from my neighbor who was buying a bigger one for himself. I changed the oil in it (5w30) with some Motul I had on hand already, and had to change the broken primer bulb. Done and done. Filled with stabilized gas, and good to go.

This model has an electric start but I used the pull cord and it fired right up. *But, I don't understand the choke settings.*

I've only used fuel-injected engines, so I'm confused. I've read up on carburetors and how they work, so I understand what the choke is trying to do, I just don't know how to manipulate it effectively. 

My snowblower is a Craftsman 21", model 247.88705... I have the manual, but the pictures are different. I've attached a picture below to describe what I mean. 










Basically, the choke says "Choke" on it, with a picture on the bottom. I don't know what's "on" or "off" - the manual suggests that there's a choke on the bottom and a run at the top, but I don't see run.

Throttle is straightforward, and I've read on the forum that this should be at full rabbit the whole time except for maybe a minute when I let it "idle" to cool down after I'm done clearing snow.

Directions from manual on starting: 
1. Throttle to Rabbit
2. Choke on (where???)
3. Primer 3-5 times.
4. Pull cord to start (no trouble here).
5. Rotate choke to off position. "If engine falters, restart engine and run at half-choke for a short time, then rotate to OFF."

So, here's my problem. When I touch the choke to rotate it upwards (in the picture, away from the carburetor picture), the engine sounds unbalanced. I let it run for 10 minutes, and the same thing happened again... Instead of a nice, balanced purrrrrrr sound, I get more of a vroom, (no sound), vroom, (no sound), vroom... like a V6 would sound like if only 3 cylinders were firing?

Thanks for your help. I haven't used it yet in actual conditions. Also, how long does this thing need to warm up before I take it from full choke to half choke to no choke?


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## vinnycom

choke "on" means the choke "plate" is fully "closed" which means less air entering carb for a better cold engine start.
choke "off" means choke "plate" is "open" so more air can enter carb for "normal" operations of motor once started.
choke means less air, so "on" means its choking motor of air.

first start, cold engine, it only needs lees than a minute, sometimes seconds for choke plate to be in the full "on" position, roughly a minute in half choke and sometines not even. 10 minutes is way too long to be on choke unless u need a carb clean or adjustment


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## crazzywolfie

where you have the choke knob in the picture is full choke which is where you want it for starting and you turn it up for running. it sounds like the jet in the carb might be partially clogged if it starts surging when you open the choke. it is usually a pretty easy thing to clean. with that engine you can usually tip the machine up on the bucket and pull the 10mm bolt out of the float bowl and pulling the floar bowl off. then use a piece of telephone wire with casing removed and running it thru the jet which is right in the where you pulled the bolt from. usually that fixes most carb issues.


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## Pilot1226

Hey,

Thanks for the replies. I'll try to get it started tomorrow morning with the settings you've both suggested. Again, carbs are unknown to me, so if I can't get it working, I'll probably try to sell it to someone for the $50 I paid my neighbor for it and invest it into an electric one since it's maintenance free. 

Thanks for your suggestions.


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## crazzywolfie

it is still a lot easier to sell and you can get a bit more for it if it is at least running good. it is a super simple fix. i have worked on couple of those. once you clean the jet it will run good and it is about a 2 minute fix requiring a 10mm socket and ratchet


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## Pilot1226

crazzywolfie said:


> it is still a lot easier to sell and you can get a bit more for it if it is at least running good. it is a super simple fix. i have worked on couple of those. once you clean the jet it will run good and it is about a 2 minute fix requiring a 10mm socket and ratchet


Okay. I have the tools, I just don't have the know-how. I've changed the oil in it (and my cars, too, so I'm willing to get my hands dirty) I just don't know where to start. You have some clear directions for me and I'll give it a shot.


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## vinnycom

Pilot1226 said:


> Okay. I have the tools, I just don't have the know-how. I've changed the oil in it (and my cars, too, so I'm willing to get my hands dirty) I just don't know where to start. You have some clear directions for me and I'll give it a shot.


there are so many vids on howto run a sb, clean a carb, repair almost any part of a sb.
is it hard? no. simple tools, no mechanics licence needed, but it is a learning curve but only a short one.
donyboy73 has plenty of vids on fixing and running a sb


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## cranman

If you are near SE Massachusetts, I'll give you the $50


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## tlshawks

How warm was it when you try starting it?

If it's say 30 degrees or above, you may only need to "half-choke it", or possibly not at all.


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