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Discussion Starter #1
Hey guys, new to the group. I’ve been working on an older noma snowblower with a 5hp tecumseh engine. Bought it not running. Replaced the fuel lines on it. Popped the carb in an ultrasonic cleaner for a couple hours cleaned it up and replaced the needle and seat.Has a newer plug in it. The unit will fire up. Runs fantastic for 30 seconds, then chugs/spits flames out of the muffler then dies. I tried removing the gas cap to rule out a vacuum but no change?

Could anyone steer me in the right direction?
Cheers
 

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Welcome to the forum!

Will it do this repeatedly? Like, will it re-start right after it dies?

Are you getting good fuel flow, if you pull the line off at the carb? Is there a fuel filter, either on the lines, or maybe in the tank?

When it starts to die, if you add choke, or push the primer button, will it keep going? Do you have spark after it dies?

Have you checked your valve clearances? Perhaps as it heats up, the exhaust valve is expanding, and no longer seats properly, due to the valve clearance being too small. That could be consistent with flames out the muffler, if the valve stops closing fully.
 

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Discussion Starter #3
So I played around with it some more. Have lots of fuel coming up to the carb. Pulled the carb back off. Cleaned it out again. Removed and reinstalled the seat. Reset my float. Must of been running a little lean but it’s perfect at full throttle now. But now I’m at my next hurdle. It’s all good until I engage the auger. The rpms drop way down. And tried to put it through 4cm of fluff and it died.

Compression is 115. Spark looks good.
 

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Is the governor functioning properly, and connected properly? Sometimes there are multiple holes that the governor links can go into. If you watch the carb while applying a load (going into the snow), is the governor actually opening the throttle?

You could also briefly open the throttle plate manually, just quickly, to see if it's starving for gas when the throttle opens. With no load, even at full RPM, you're likely running mainly off the low-speed jet. Once a load is applied, and the throttle plate opens, you'd change over to the main jet. Just in case that one is somehow not providing enough fuel.

As an easy test, you can try adding partial & full-choke, when going into the snow, to see if anything changes.
 

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Discussion Starter #6
If I hold the auger engaged and turn the main screw it’ll start to rev up for me. But if I let off the auger the rpms shoot up really high and then I start to get a lot of popping out the muffler
 

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"turn the main screw" . . . as in main jet? Might just be too lean . . . The jet doesn't set speed, the gov does, so if that is what you are turning, and it's overspeeding, the gov is wonky.
 

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Yeah, I have fixed jets stuck in my head. After my last post it occurred to me that maybe your carb still actually has adjustable jets, which would be great.

Which is this "main screw"? Under the center of the bowl? As tadawson said, that's the main jet, adjusting the mixture for higher throttle settings.

If the RPMs stay high after you remove the augers load, then I'd suspect maybe your governor is sticking somehow, despite you saying that it is *opening* the throttle under a load.

And if it's dying under a load, but not blowing black smoke at the same time, maybe it's running lean when the throttle opens. Unscrewing the main jet, under the center of the carb bowl, should richen the mixture, giving it more fuel. I'd try to make small adjustments to the jet, maybe 1/8 turn at a time, max.
 

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Discussion Starter #10
Yeah so I’ve got my main jet and my air screw on the side. Set them to 1.5 on the main and one out on the air screw.

Fire it up and it runs great at full throttle. Then when I engage the auger the rpms come way down even tho the throttle plate is wide open. While it’s running like this with the auger engaged, I can turn the main jet and get my rpms to come back up.then upon releasing the auger the rpms go way back up. It’s like I can’t find an inbetween for no load and load.

That’s where I’m confused between the fuel and governer
 
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