# Hole in carburator



## timdagolfer (Nov 7, 2021)

I have an MTD model 316-611D000 snow blower. I put gas in it and I see it running out. Upon inspection I found a hole in the side of the carburator body. Has anyone ever heard of this before?


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## Oneacer (Jan 3, 2011)

I have never seen a whole in the side of a carburetor that was not intentionally put there for a screw or the such.

LOL .... Maybe it was stored outside, water got in and it froze and popped a plug? ?


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## cpchriste (Jan 19, 2014)

Tecumseh carbs have a vent hole in all their carb bodies. Pic please.


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## Oneacer (Jan 3, 2011)

Yeah, I would like to see the hole he is referring to that should not be there.


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## timdagolfer (Nov 7, 2021)

Oneacer said:


> Yeah, I would like to see the hole he is referring to that should not be there.





Oneacer said:


> Yeah, I would like to see the hole he is referring to that should not be there.


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## timdagolfer (Nov 7, 2021)

timdagolfer said:


> View attachment 182503
> View attachment 182503


I have fixed a lot of carburators and have never seen one get a hole in it. Everything was drained last winter so nothing froze and it was stored inside. I am clueless. Planning on buying a new carburator.


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## Tony-chicago (Feb 10, 2021)

Poor casting with a mold that is littered with at least one low pressure spot. Rattle around a while and voila. Okay wag. But that seems to be best guess


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## timdagolfer (Nov 7, 2021)

Tony-chicago said:


> Poor casting with a mold that is littered with at least one low pressure spot. Rattle around a while and voila. Okay wag. But that seems to be best guess


Thank you. I tend to agree.


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## sledman8002002 (Jan 20, 2021)

Looks like a vent hole to these tired eyes. In my experience, if its leaking while not running, there's debris on the needle/seat and/or a float issue.
Pull the bowl off and have a look to start with.


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## tadawson (Jan 3, 2018)

Sounds like a stuck float - the fuel level should never get that high. Pull the bowl and take the 2 minutes to check it . . .


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## Yanmar Ronin (Jan 31, 2015)

Agreed check the float and needle first.

And welcome to SBF Tim, glad to have you here.


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## Tony-chicago (Feb 10, 2021)

Much better explanation. I assumed things were checked out first. Should have known.


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## timdagolfer (Nov 7, 2021)

Yanmar Ronin said:


> Agreed check the float and needle first.
> 
> And welcome to SBF Tim, glad to have you here.


Thank you everyone for all the replies and welcoming me. I will check the float and needle valve first. I appreciate you all!!


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## Oneacer (Jan 3, 2011)

Oh, I did not know if was coming out the carburetor throat... Then indeed check you float and needle valve.


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## Ziggy65 (Jan 18, 2020)

Yes the fuel level should never reach the vent hole on the carb, you can find instructions on adjusting the float level in the attached manual.


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## oneboltshort (Dec 16, 2019)

Yellow is atmospheric vent (hole).


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## EntropyKnower (Aug 27, 2021)

Taryl explains it here:
Says the bowl will overflow if the vent is not clean:




*How To Rebuild Tecumseh Snow Blower Carburetors with Taryl*


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## Oneacer (Jan 3, 2011)

Hmm... interesting ...I know many people miss the second miniscule hole in the main adjusting needle on the adjustable carbs, but honestly, I don't recall checking for that exterior case vent hole when cleaning one.


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## timdagolfer (Nov 7, 2021)

Oneacer said:


> Hmm... interesting ...I know many people miss the second miniscule hole in the main adjusting needle on the adjustable carbs, but honestly, I don't recall checking for that exterior case vent hole when cleaning one.


Hello Everyone. I'm sorry it took so long to respond but work and life got in the way. I finally got back to my snowblower and took everyone's advice. I pulled the carb, took it apart and cleaned it, checked the float and the needle valve. I also replaced the fuel line. Put it back together and my snowblower is running perfectly. I appreciate everyone and you taught me about that vent hole. There are so many knowledgeable people out there and I think you are all wonderful for wanting to help people. Thank you again!!


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## cpchriste (Jan 19, 2014)

EntropyKnower said:


> Taryl explains it here:


At the 23 minute mark Taryl starts talking about a loose tube inside drilled passages in the idle circuit. Anyone have experience confirming its existence? I've never noticed this "sound" and I wonder how this tube could ever move once corrosion set in.


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## EntropyKnower (Aug 27, 2021)

cpchriste said:


> At the 23 minute mark Taryl starts talking about a loose tube inside drilled passages in the idle circuit. Anyone have experience confirming its existence? I've never noticed this "sound" and I wonder how this tube could ever move once corrosion set in.


I think Taryl doesn't get that quite right: I believe what he is talking about is not a tube, but is a "metering rod or pin in fuel transfer passage" in the pilot circuit, and it is not present on all models. I have a Series 3 carb, and I haven't been able to detect the rod, but my carb seems to work okay. 

Somebody please confirm or deny: I think the rod, if present, is inserted from below and is retained by a plug. But presence of the plug doesn't imply that a rod is actually installed or supposed to be installed on the particular model. If the rod is moving freely, you can hear it rattle or see it through the idle-mixture screw hole when the screw is removed. I don't think you can obtain the rod as a separate part, so if you mess it up by tightening the idle-mixture screw onto the rod, then you are going to need to replace the carb. The most likely way of damaging the rod is to tighten the idle-mixture screw while holding the carb upside down.

See page 10 of:








TECUMSEH SERVICE REPAIR MANUAL 3 HP TO 11 HP 4 CYCLE L HEAD FLAT HEAD ENGINES 692509 : Ariens, tecumseh : Free Download, Borrow, and Streaming : Internet Archive


This manual covers engine models:ECV100 - 120, H22 - 80, HH40 - 70, HHM80, HM70 - 100,HMSK70 - 110, HMXL70, HS40 - 50, HSK30 - 70, HSSK40 - 50,HT30 - 35,...



archive.org




Tecumseh Technician's Handbook, 3 to 11 HP 4-Cycle L-Head Engines


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