New carb???

My troybilt snowblower always ran great. Till last week refused to start. I put on new carb, huayi 170-s type and it ran awesome. For 1/2 hr. Shut it off and 3 hrs later it refuses to start. Dead again. New plug. New gas. Wtf? Ran super. Shutoff. Won't start. With new carb? Even put old carb on. Waste of time. New carb is back and it runs now at 1/2 throttle but won't go full speed. Is this a fuel issue? Good spark too.

Cavell said:

My troybilt snowblower always ran great. Till last week refused to start. I put on new carb, huayi 170-s type and it ran awesome. For 1/2 hr. Shut it off and 3 hrs later it refuses to start. Dead again. New plug. New gas. Wtf? Ran super. Shutoff. Won't start. With new carb? Even put old carb on. Waste of time. New carb is back and it runs now at 1/2 throttle but won't go full speed. Is this a fuel issue? Good spark too.

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:welcome: Troy Bilt made your snowblower but they did not make the engine so lets start with the basics.
What engine is in there ?
Next get an inline spark tester and hook it up to confirm you are getting a spark

Locate the governor lever , start the engine and move the lever by hand slowly to see if you can manually make the engine run full speed ( Don't over do it ).

Let us know how you go.

Has a 208cc power more motor. It's a chinaclone. Lowes special. It's not Briggs, not Tecumseh, it's the Honda clone special. Thought everyone was aware of these motors? Original carb is the huayi 170-s. The new carb is 89% identical but it has a adjustable mixture screw on side where the huayi has a plug. I did not touch this screw. Spark is nice and blue/hot. 2 days ago it started on 1st crank. Throttle lever works fine. Motor will run with no choke and will idle at "zero" lever position. Motor never would idle that low with old carb. So, it ran perfect for 1/2 hr. 1/2 speed, 3/4 speed, full speed. Shut it off and 3 hrs later it refuses to start. Wtf?

If possible put a small amount of gas into the intake and see if it will start and keep running or run and then die. If it has a primer can you see it push fuel into the carb venturi when pumped. Sounds like something is possible clogging the fuel jet in the carb, but could be related to other issues so let us know.

And people need to stop treating those chinese honda clone engines as there own separate item. If you have a briggs, honda, kohler, kawasaki engine then they are treated as a separate piece of equipment for repairs, the Loncin, Rato, Power more, and some of the LCT engines are part of the piece of equipment and parts are sold thought the equipment manufacturer and not the engine manufacturer. The powermore engine is a MTD engine, the LCT on a Husqvarna product is a Husqvarna engine, a Loncin engine on a Toro is a Toro engine. The Loncin or Rato on a Generac is a Generac engine.

i put the old carb back on as it is not real hard. it sorta started and backfired and popped and really did not like it. so, i put the new carb back on and i think i figured out throttle needs to be at 1/2 speed appx and it will start/run. no choke. it ran ok enough to let me blow out the driveway again but anytime i tried to increase throttle to 3/4 or higher it would stumble and bog down. seemed to run ok at 1/2 throttle. but it wont throw snow very far. each time i change carbs i have to drain what little fuel is in tank. so i have filled/drained tank about 5 times. maybe its the gas now as i am doing this in open garage and it was snowing and maybe the gas is water contaminated now? i am going to drain the tank again and dump out the gas can and get fresh fuel from another station. i can get non-oxy gas but i dont see how E-10 would affect a brand new carb.
i do see a bit of blackish smoke when the unit is running. too rich? should the mixture screw on side need adjustment as it is new? how many turns in is it set too now? 1-1/2?

Screw on side should be for idle speed. Can have some effect on high speed load, but not much. If you try to go above 1/2 throttle, does is just bog down like it is running out of fuel, or does it start to blow black smoke out the muffler like it is too rich. Sounds like a carb issue, but other things can also effect running, Like a flywheel key partially sheared effecting timing, or a valve that is out of adjustment.

I wonder if the screw on the side might be some sort of mixture or atm. adjustment. Wouldn't hurt to tinker with that. Screw it in and see how many turns it takes to bottom out so you can reset it. Then open to that setting and give it 1/2 turn or so more. Really sounds like a piece of dirt in the main jet though. A picture of the carb would help some here.

this is ebay pic and i just noticed there is a plug in the pic where i have a screw. they dont even send the actual carb that is in their ad. thats funny. i did remove the main jet and it is spotless. its new, why not? hole is open. i drilled out my jet on old carb 2 yrs ago and it runs the same as before. i think the new jet is #74-75? certainly smaller than my old jet is.
this is pic of my old carb. the huayi model. you can see the plug on the left side. my screw has a tension spring also for the screw.
pic shows my magic tool box. i am kinda a mad scientist. i work on various auto projects all the time. yes i know the float bowl is askew. i removed it and reseated it properly

tom3 said:

I wonder if the screw on the side might be some sort of mixture or atm. adjustment. Wouldn't hurt to tinker with that. Screw it in and see how many turns it takes to bottom out so you can reset it. Then open to that setting and give it 1/2 turn or so more. Really sounds like a piece of dirt in the main jet though. A picture of the carb would help some here.

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Need to be very careful about adjusting some of those screws on the side. On some carbs they are designed to break off if somebody attempts to turn them. The picture posted in the post after yours shows a picture of the carb of the type of carb that he is using, and the adjustment screw is broken off in the picture.

ILENGINE said:

Need to be very careful about adjusting some of those screws on the side. On some carbs they are designed to break off if somebody attempts to turn them. The picture posted in the post after yours shows a picture of the carb of the type of carb that he is using, and the adjustment screw is broken off in the picture.

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Hey IL Engine ........ I don't see a broken screw on his carb ....... Unless you are talking about the black idle screw on top holding down the idle port jet......

That's another thing that should come out and get a damn good cleaning.... As much as sneaux blowers set up the idle jets get gummed up and sometimes the only way to get em right is to take a thumb bit and ream it out ........

Plus Tard ............