# Engine stops running after 45+ minutes



## SteveBinNev (3 mo ago)

Hello everyone! Newbie here with a perplexing (for me) issue and could really use some guidance from the experts on this forum. A good friend gave me a 2003 Craftsman 11/30 that needed work after years of sitting. I replaced the carburetor with a brand new one, installed a new gas line from the tank and added a fuel cutoff valve, changed the oil, and gave it a good cleaning, sanding etc. The two belts looked "ok" and functioned well in drylands yet runs (auger spins, forward/reverse speeds are fine) but I'm plan to replace them soon anyway like I should have done over the summer. 

I used the blower for the first time in early December and it ran fine though I didn't clear that much so it did not run for a long time. This morning I cleared two driveways after yesterday's storm that left 10" of wet Sierra cement. Overall the blower performed well. The impeller mods really helped, throwing cement 20'... nice! The engine runs well given what it's been through. It fires up on first pull after a bulb prime and runs strong. At full throttle the engine will "cough" a tiny tiny bit but outside of that it's fine.

After 45-55 minutes of clearing (the longest I've run it) the driveways this morning, I moved on to the sidewalks and oddly the engine stalled. I had to prime the fuel to get it to start again. I don't have to re-prime the fuel if I stop and restart the engine so I thought that was odd. I resumed clearing the sidewalk and after a minute it stopped again. Time for some science to figure out what is going on so I did a test where I start it and then just let the engine idle without running the auger. Same result. The engine ran for about a minute maybe less then sputtered and died. Each time this happens I have to prime the fuel to get it to start.

So my novice brain is telling me it's not drawing fuel from the tank for some reason. The short run time is likely from burning the fuel that I brought into the carburetor via priming. There's plenty of gas in the tank and the engine was running fine for nearly an hour so it's not gas quality etc. (It's brand new gas with stabilizer added). This only happens after running just fine for nearly an hour.

Looking for your guidance here.... I searched around before posting to see if someone else had this issue but I didn't find something so starting a new post...

TIA,
Steve


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## cranman (Jan 23, 2016)

Gas cap vent not venting I suspect


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## 1132le (Feb 23, 2017)

yup unscrew gas cap next time it starts to stumble


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## Big Ed (Feb 10, 2013)

My guess too, gas cap not venting, an easy fix if the vent is not venting.


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## HasseBF (2 mo ago)

My blower with a 9 hp Tecumseh does that when the fuel level starts to get low. Looking down the tank its easy, at least for me, to misjudge the amount of fuel in it. Seems like it needs the pressure from the weight of the gas to get a good fuel flow.


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## SteveBinNev (3 mo ago)

1132le said:


> yup unscrew gas cap next time it starts to stumble


Interesting... I learn something every day... as my wife frequently points out to me. 

When you say unscrew, should I just loosen it or do I literally unscrew and take it off? Seems dangerous to do the latter?


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## 1132le (Feb 23, 2017)

loosen it enough to let air in if it runs better your cap is junk like mr cranny side


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## Big Ed (Feb 10, 2013)

SteveBinNev said:


> Interesting... I learn something every day... as my wife frequently points out to me.
> 
> When you say unscrew, should I just loosen it or do I literally unscrew and take it off? Seems dangerous to do the latter?


Most of the time it would shut off sooner. If the cap is not venting it creates a suction holding the fuel from flowing.
So yours might be venting a little as it takes a long time to stop the flow.
Try taking out some of the gas and see what happens with the cap off. Or run it till it stops, then take the cap off to relieve pressure and put the cap back on tight and run it again, if it runs fine after you take the cap off your cap is shot or the vent is blocked. Some have a rubber flapper in the cap so it sucks air in but prevents gas from spilling out.
Most likely that is your problem.
Edit, Gas caps are not that expensive. Search with your serial numbers.


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## 1132le (Feb 23, 2017)

Big Ed said:


> Most of the time it would shut off sooner. If the cap is not venting it creates a suction holding the fuel from flowing.
> So yours might be venting a little as it takes a long time to stop the flow.
> Try taking out some of the gas and see what happens with the cap off. Or run it till it stops, then take the cap off and run it again, if it runs fine after you take the cap off your cap is shot or the vent is blocked. Some have a rubber flapper in the cap so it sucks air in but prevents gas from spilling out.
> Most likely that is your problem.





Big Ed said:


> Most of the time it would shut off sooner. If the cap is not venting it creates a suction holding the fuel from flowing.
> So yours might be venting a little as it takes a long time to stop the flow.
> Try taking out some of the gas and see what happens with the cap off. Or run it till it stops, then take the cap off and run it again, if it runs fine after you take the cap off your cap is shot or the vent is blocked. Some have a rubber flapper in the cap so it sucks air in but prevents gas from spilling out.
> Most likely that is your problem.


most of the time
a partial clog it can happen
my 414cc lct did it i was shocked it took 40 min myself


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## Big Ed (Feb 10, 2013)

1132le said:


> most of the time
> a partial clog it can happen
> my 414cc lct did it i was shocked it took 40 min myself


My neighbors power washer would run for about 30 mins then stop.
He tried blowing air thru the cap hole, but it didn't help.
A new cap fixed it.
Right before it would stop the engine would stutter and run rough, then eventually stopped running.
He did a whole house by timing it and loosening the cap.
Then he spent an hour trying to fix it, he hates buying anything, he finally bought a new cap.


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## 1132le (Feb 23, 2017)

Big Ed said:


> My neighbors power washer would run for about 30 mins then stop.
> He tried blowing air thru the cap hole, but it didn't help.
> A new cap fixed it.
> Right before it would stop the engine would stutter and run rough, then eventually stopped running.
> ...


i drilled a hole in mine it fixed it called ariens mentioned the recall about the cap she said but not your model number
i said i have the 414cc same motor as recalled cap
she said you are not the orig owner 
i said so what its a recall ive had 40 plus ariens blowers recommend them alot and mentioned the ariens rep from here
she sent me the revised cap
ariens= good customer service


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## Big Ed (Feb 10, 2013)

1132le said:


> i drilled a hole in mine it fixed it called ariens mentioned the recall about the cap she said but not your model number
> i said i have the 414cc same motor as recalled cap
> she said you are not the orig owner
> i said so what its a recall ive had 40 plus ariens blowers recommend them alot and mentioned the ariens rep from here
> ...


When you drilled the hole did it leak when the tank was full?


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## WVguy (Nov 24, 2018)

A remote possibility (and I agree the gas cap is the most likely culprit here) is that when the ignition coil is heated from warmth from the engine it gets an "open" in the circuit and then when it cools down the open closes and it will fire again. But I agree fuel supply is most likely the issue.

This is rare and doesn't really fit the description (not enough cool-down time between restarts) but it is something to think about after all other possibilities have been exhausted. The Canadian guy Bruce on youtube has run into this a couple of times and did videos on it.


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## SteveBinNev (3 mo ago)

Thanks everyone for your insights. The plot thickens... I just went outside and loosened the cap to so that it was just barely on. I had to prime the bulb 8-10x until the engine would start. Odd I used to only need to prime just 2-3x. The engine runs for less than a minute then it sputters and dies. Prime again 8-10x and the cycle repeats. Also the gas tank is nearly full.

+ Doesn't seem to be a vent issue if the cap is barely on but it's still sputtering out?

+ The tank was bone dry and appeared clean to me when I got the blower. I installed a new fuel line and carb. Also started this cycle with fresh gas in my filler tank so debris not likely the culprit? Plus it ran for almost an hour this morning although it won't do that now...

+ Doesn't seem to be an engine-heating-up issue because the blower has been sitting outside in 32 degree weather for at about 4 hours before this most recent test. Or maybe it needs longer to cool down? 

+ I checked carefully for gnomes, gremlins, Santas elves or anything that could disrupt/restrict gas flow. Not seeing anything... although I didn't pull off the covers etc to see if the gas line is pinched somewhere? I mean its only like 6-8" of travel from one side of the engine to the other, but maybe?


The priming seems to be an important clue here. When I first replaced the carb/installed a new fuel line and cutoff valve, I could feel the gas rushing in when each push of the priming bulb. I'm sure you know that feel, like there's a little resistance because it's pushing the gas over. I can also hear the rushing sound of the fluid moving. Now I have to push the bulb many times before enough gas gets into the carb to start. I don't hear the gas rushing sound on the initial presses and it just feels like air versus that resistance-from-fluid feeling. 

Thanks everyone for your investigative skills and opinions here. Experience matters and I have none with snowblowers but I do like a good mystery! And yes I love to watch crime shows!


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## 1132le (Feb 23, 2017)

Big Ed said:


> When you drilled the hole did it leak when the tank was full?


no


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## WVguy (Nov 24, 2018)

Now I'm thinking crud in the fuel line blocking it. Turn the fuel valve off, have a cup or something to catch fuel, turn the fuel valve back on, and then pull the fuel line away from the carburetor to see if the fuel is flowing freely. I bet it does not.

Some fuel tanks have a built-in fine mesh fuel filter and that MIGHT be what is going on here given the age of the snowblower. Try using a flashlight to look into the fuel tank when it is empty and see if there is a filter in there. Or try pulling the fuel line from the bottom of the tank, some filters are inside the fuel line there. But of course you want the tank empty when doing this.


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## 1132le (Feb 23, 2017)

SteveBinNev said:


> Thanks everyone for your insights. The plot thickens... I just went outside and loosened the cap to so that it was just barely on. I had to prime the bulb 8-10x until the engine would start. Odd I used to only need to prime just 2-3x. The engine runs for less than a minute then it sputters and dies. Prime again 8-10x and the cycle repeats. Also the gas tank is nearly full.
> 
> + Doesn't seem to be a vent issue if the cap is barely on but it's still sputtering out?
> 
> ...


primer line is sucking air or junk
doubt its related


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## Cstanis (Oct 19, 2021)

Did you check the condition of the primer bulb for cracks? Is it possible the primer hose may have pulled off? Those are a couple of things that could explain the need to prime it more. Even though you installed a new carb doesn't mean is hasn't picked up dirt or had issues from the start. I have had several Chinese carbs have burrs in the emulsion tube and needed to be cleaned


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## UNDERTAKER (Dec 30, 2013)

*Just might be junk in the bottom of the tank. Or built up condensation in the tank. Or water in your fuel source.*


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## vangasman (Oct 21, 2021)

The primer does not actually move fuel like a small weedeater style carb, it applies positive pressure to the top of the fuel bowl forcing fuel up the main jet. You said you added a fuel shut off, most of these did not come with one. Maybe causing the fuel line to be too low to flow properly.


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## SteveBinNev (3 mo ago)

Thanks everyone for your suggestions. It's given me the direction necessary to set a plan of attack for today. I plan to pull the gas line at the carb and check flow to determine if there is a blockage somewhere upstream or if the cutoff valve I installed is impending flow because of the drop where the vale is. If the flow is too low then I'll research from there and modify or remove the cutoff valve I added. 

If the flow looks good, then I'll look into the primer bulb setup. I installed the new one that came with the carb I purchased so maybe it's not pushing air into the fuel bowl as stated above. 

But the big thing I discovered this morning was that in all the research this past fall to buy a new carb, it looks like I bought the wrong one? I'm new at working on small engines but am learning so much especially from my mistakes. It was a lot of work for me to figure out what engine model is on the blower. I couldn't find a Tecumseh engine id stamped anywhere but I found a Sears model id then found online a Sears-to-Tecumseh crossover list on the web, which lead to the Tecumseh engine ID and then the carb part #.

I used Amazon to find the right carb and had put several potential choices into the shopping cart to hold them, and then went back to the cart with the short list and picked the one I want. Maybe I had a few beers that day but somehow I bought the wrong one! Idiot! I didn't give it a second look when the carb arrived. The fittings were the exact same dimensions so I thought of course this is the right one. 

The carb I purchased is for HMSK80 or HMSK90, located here: https://www.amazon.com/gp/product/B01N2HLDIY

The engine I have is an HMSK110.
(FYI the Sears ID is 143.041101, which lead me to this -> "HMSK110 - 159967C 911307 756340B")
Jacks small engines has a parts list for this engine and identifies the carb as Tecumseh 640349.

But looking at Amazon this morning there are _so_ many of these Chinese-manuf carbs out there but I don't see an exact match on HMSK110 and 640349. There are many options for HMSK110 but have a different carb part #. And the HMSK110 compatible carbs also list 8hp, 9hp etc like the one I bought.

I'll look at Amazon and other web sites later after I examine the fuel line situation. Any advice or direction of how to best navigate the quagmire of carburetor replacements would be most appreciated. Same goes for how I arrived at the engine id/carb part#.

Thanks everyone!
~Steve


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## cpchriste (Jan 19, 2014)

My prime suspect would be the cheapo fuel valve shipped with the carb.


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## Ziggy65 (Jan 18, 2020)

Yes, if the fuel shut off and the primer you installed came with the cheap carb, I would replace both with quality parts. Usually the cheap knock off fuel shut offs leak after a few days or months, but it could be restricting fuel flow as well.
I toss all the items that may come with the cheap Chinese carbs (fuel line, fuel filter, primer, shut off valve, spark plug etc) into the trash. I will use the gasket if it came with one if the old one is damaged.

Compare the new carb to the old one, is it physically the same? similar choke and throttle plates for linkages?
I think the carb you purchased should work on your engine.

A couple of Tecumseh manuals:


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## SteveBinNev (3 mo ago)

Ziggy65 said:


> Yes, if the fuel shut off and the primer you installed came with the cheap carb, I would replace both with quality parts. Usually the cheap knock off fuel shut offs leak after a few days or months, but it could be restricting fuel flow as well.
> I toss all the items that may come with the cheap Chinese carbs (fuel line, fuel filter, primer, shut off valve, spark plug etc) into the trash. I will use the gasket if it came with one if the old one is damaged.
> 
> Compare the new carb to the old one, is it physically the same? similar choke and throttle plates for linkages?
> ...


Wow those manuals are very helpful thank you! Yes the carbs were physically the same except for the bottom of the fuel bowl. The old one had two screws, one looked like it was for adjustments and the other was something I could depress to drain the fuel from the bowl. The new one doesn't have the drain thingy and there's a fixed bolt in the center of the bowl that doesn't adjust. Outside of that, the carbs (choke, throttle etc) were the same. So maybe this carb will work? Going to head out soon to check the fuel flow... Thanks for the manuals! Nighttime reading!


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## tadawson (Jan 3, 2018)

Sounds like you got the downgraded, EPA crippled version of your carb as a replacement . . .


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## SteveBinNev (3 mo ago)

tadawson said:


> Sounds like you got the downgraded, EPA crippled version of your carb as a replacement . . .


Yikes can I buy the climate-change muscle-car version? Or is that now contraband?


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## SteveBinNev (3 mo ago)

Update: Problem solved (hopefully) !!!

I started to remove the fuel line from the carb but it's a very tight, fit likely because the hose is cold. I couldn't get it to budge off the carb nipple unless I cranked on it with pliers. Fearful that I would nick or tear the line, I figured there has to be some trick to get the dang thing off (warm it up etc). So after a quick pause I changed direction and researched the primer bulb. Turns out the primer line has a big cut in it halfway between the bulb and carb. I grabbed the old primer bulb/line which I kept, connected it to the carb directly without threading it around the engine, and primed the fuel. The engine started on its first pull and it ran just fine!

Back when I installed the new primer bulb and line, I just pulled out the old hose and then shoved the new one in from the top until I saw it come out the bottom. Pretty easy or so I thought. I did not do the trick of connecting the new hose to the old hose and then pulling it through. I ran the new fuel line using that trick but the primer line seemed so easy so I just shoved it through. Well I guess there is more to it because the primer line looks like it came in contact with heat or something else and made a cut almost all the way through the line.

I'll do some research to figure out how to thread the line correctly given that my "guide" of the original primer hose path is not available any more. If it's a pain to do now, I'll just gerryrig it until after the season. It's temporary anyway because I plan to swap out the junk parts with quality replacements. With luck all of this can wait until after winter. It's more fun to work on it during the summer!

Thanks everyone so much for your help. As my dad always told me, making mistakes is the way you learn!


Until the next storm,
Steve


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## tadawson (Jan 3, 2018)

SteveBinNev said:


> Yikes can I buy the climate-change muscle-car version? Or is that now contraband?


The adjustable, pre-EPA (read: adjustable, work far better) versions are available from your faborite offshore sources . . .


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## Big Ed (Feb 10, 2013)

If that is your problem I wonder, if it was a big cut........didn't it leak?


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## SteveBinNev (3 mo ago)

Big Ed said:


> If that is your problem I wonder, if it was a big cut........didn't it leak?


The air line was nearly cut in half in between the carb and the primer bulb, up inside the engine housing somewhere. The cut was well above the carb so nothing would leak out, but with the slice it would likely act as though the hose wasn't even connected to the carb. Guessing that there needs to be some sort of air resistance/vacuum to ensure proper fuel flow in the carb?


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