# HS80 Idle Surge



## sr73087 (Feb 9, 2017)

So I picked up an HS80 last week before the blizzard talk. It looks to have an aftermarket carb on it and has a small idle surge while cold. The surge goes away completely under any load. Does this happen with newer aftermarket carbs on older equipment or likely an issue with a jet?


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## alphaboy123 (Oct 27, 2016)

Sounds like a dirty carberator perhaps? I had this with my hs55 and ran some Seafoam in the gas and it cleared it up.

Sent from my SM-N910P using Tapatalk


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## YSHSfan (Jun 25, 2014)

May be a dirty carb. Clean it up real good and see what happens....


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## JLawrence08648 (Jan 15, 2017)

Usually dirty idle holes. There are 2 or 3 holes next to the choke plate, they are also covered by a Welch plug on the side of the carburetor. A good carb cleaner sometimes works but it also sometimes takes awhile to work so don't get discouraged. You can try some spray carb cleaner with a plastic red tube attached and spray it in the holes.


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## sr73087 (Feb 9, 2017)

How similar internally is the GX240 carb vs the GX390? 

I ask because there are some great writeups at the link below on carb disassembly and its nice having a better idea what you are going into. Either way I think I am going to wait until after the coming storm to mess with this. 

Disassembly, Cleaning and Repair of Carb 16100-ZF6-W10 on Honda GX390 QA2X Engine


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## 43128 (Feb 14, 2014)

they are practically the same carburetor


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## YSHSfan (Jun 25, 2014)

sr73087 said:


> Either way I think I am going to wait until after the coming storm to mess with this.


Yes and NO.
One of my Honda HS828 had a symptom like that, and I took the waiting route, storm came, started trying to blow ~8" of snow, it was a no-go, it'll bog and stall (this may not be your case and you'll be fine but just wanted to share my experience).
You may want to clean it using seafoam in the gas tank, and/or cleaning it without major disassembly, this way you won't risk being without the snowblower for the storm.


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## sr73087 (Feb 9, 2017)

I have a backup but it's a small ariens. It might not be up to possibly 2' of snow. I think I'm going to chance it a mess with it today. I had an issue a few years ago and had to shovel 34" by hand, not trying to deal with that again.


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## JLawrence08648 (Jan 15, 2017)

I have to apologize, I gave a description of a Tecumseh carb not recognizing it was a Honda. Whoops!


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## sr73087 (Feb 9, 2017)

JLawrence08648 said:


> I have to apologize, I gave a description of a Tecumseh carb not recognizing it was a Honda. Whoops!


No problem. I always appreciate the help.


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## sr73087 (Feb 9, 2017)

Ok so its running very well now. No surge at all. I did a combination of things, so I'm not 100% which fixed it. 

-Checked pilot and main jets, they were very clean, almost nothing in the bowl either. Carb is definitely not original. 
-Changed plug, old plug was technically not the right one. Very very close but a different NGK part# than what Honda says it should use
-Adjusted the valves, they were both very tight. I think this is likely what fixed it since everything else was not really an issue. 

Thanks everyone for your help.


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## YSHSfan (Jun 25, 2014)

That is good to hear...., enjoy the snowblower....!!!!


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## Molly2175 (Oct 21, 2014)

To all the Seafoam users and fans. Just a word of warning. With Seafoam if a little is good----a lot will kill it. 

The Seafoam is designed for large tanks of gas. 15-25 gallon range. The small tanks on your snowblower, lawnmower, rider, garden tractor have a lot of natural rubber components that strong doses of Seafoam, dry gas, carb cleaner, fuel injection cleaner, etc. will dissolve and plug your small carb or destroy the aluminum of the body. Sometimes less is more. 

The other alternative is a new carb. The price differences between a rebuild kit and a new carb for a small Honda motor are so close that it is impractical to spend a lot of time taking apart the carb more than once to get the idle and loaded speed to work. This is from Honda, not a aftermarket clone. Tecumseh and Briggs and Stratton aftermarket carbs are also coming down in price. If you have a 15-20 year old carb that has seen a lot gas thru it, it might be a better and easier solution to replace the old carb.

Just sayin: "Marvel Mystery Oil" fan forever. Cleans carb, engine oil, valves, etc. Small doses added to gas and oil will help keep carb and engine oil clean.


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## orangputeh (Nov 24, 2016)

Molly2175 said:


> To all the Seafoam users and fans. Just a word of warning. With Seafoam if a little is good----a lot will kill it.
> 
> The Seafoam is designed for large tanks of gas. 15-25 gallon range. The small tanks on your snowblower, lawnmower, rider, garden tractor have a lot of natural rubber components that strong doses of Seafoam, dry gas, carb cleaner, fuel injection cleaner, etc. will dissolve and plug your small carb or destroy the aluminum of the body. Sometimes less is more.
> 
> ...


Interesting. how much mystery oil would you suggest per gallon of gas? per qt of oil?


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