# Craftsman 9 HP Dual Stage Engine Problem



## cableguy (Oct 7, 2011)

Hi all, and I'm glad to have found this forum! I have a Craftsman 9 HP Dual Stage snow blower(Model 536.887992) that was given to me by a good friend of mine. He said it worked fine last year until he accidently grabbed the wrong gas can from his weed whacker (gas and oil mixture) and put it into the tank. The snowblower starts up fine, but has lost power. It runs sluggish. Any ideas I can check to see if I can get this baby ready for this winter? I will gladly appreciate it. 

Thanks,


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## HCBPH (Mar 8, 2011)

Drain the tank, blow out the gas line and put a carb kit into it being sure to clean everything well. Check the sparkplug and replace as needed. Put in fresh, clean gas (I'm finding non-alcohol gas works better in some of mine), and adjust it to specs and you should be good-to-go. Be sure to thank your friend for the snowblower when you're using it and he isn't.


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## cableguy (Oct 7, 2011)

Thanks HCBPH , that's the first thing I did when I got it home, empty out the gas tank. Any ideas where I can get a carb kit for this model. How hard is it to do this? I use to work on my own vehicles back in the days, and I would love to tackle this project. 
Thanks!


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## pfn (Dec 24, 2010)

My bet is that you don't have to rebuild the carb. Running fresh gas thru the system should purge any remaining oil. The plug may be fouled, probably a good idea to replace it anyway.


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## HCBPH (Mar 8, 2011)

*Carb kit*

I'm not familiar with that model so you're going to have to do a little legwork here. First off, I'm going to make a couple of assumptions: it's more than a couple of years old and it has a float type carb.

If you have the manual, it may list a carb kit in the parts section, if not then you're going to have to track it down.
Regardless of what you do here, get the model of the engine as almost every place works off that. If yours happens to be a Tecumseh engine, it should be stamped into the top of the flywheel cover, under the starter button if you have an electric starter. If it's a Tecumseh, IIRC it should start 143xxxxx - get the whole thing. Take the model too: (Model 536.887992) just in case.

Sears should be able to get it for you. Personally I just go to my local shop and they usually have the ones I need on hand and can match it up based on the engine number.

If it's a Tecumseh or one of the other major brands, there are alot of videos on YouTube on overhauling carbs. Same thing on the Manual, I found a PDF version a while back that covers most everything on Tecumseh carbs. If yours is a tecumseh, get the pdf on the manual, it will answer virtually everything you'll ever need to know on your carb.

Biggest things to watch: changing the needle valve seat, put it in the correct direction along with being in all the way. Hooking the needle valve to the float (assuming yours has a float) with the opening in the wire pointing the correct direction. Checking float drop. Insuring that all the little holes are open and not gummed up (I suspect this is alot of your problem) and generally cleaning up everything squeeky clean. Orient the fuel bowl the right way and get the seals in correctly.

I happen to like using brake cleaner when doing carbs, it gets alot more gunk out easier than straight carb cleaner. I do it when I'm putting a full carb kit in.

Remember on an adjustable Tecumseh carb, starting adjustment is 1 1/2 turns on midrange jet and 1 turn on the main jet (be sure to loosen that one up if yours has one before installing).

Hope that helps, come back if you need further help.


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## cableguy (Oct 7, 2011)

Thanks to all of you! I have the manual at home, I will look further. I didn't want to start it till I checked with someone. 

Thanks!

According to sears chat online, Model#536.887992 is a Tecumseh #640349, and yes it has an electric start.


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## HCBPH (Mar 8, 2011)

*Carb*



pfn said:


> My bet is that you don't have to rebuild the carb. Running fresh gas thru the system should purge any remaining oil. The plug may be fouled, probably a good idea to replace it anyway.


Reason I suggested a rebuild is I've seen carbs totally gummed up (including the little holes under the one welch plug) just from stale gas. Add a gas-oil mix who knows how long it was in there and what might be out of whack. Better to start clean and fresh, especially since a full carb kit is only $10-$15 for most Tecumseh engines. If you're going to tear it down anyway, start with a known good setup.

Just my 2 cents.


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## Snowmann2011 (Apr 5, 2011)

HCBPH said:


> Reason I suggested a rebuild is I've seen carbs totally gummed up (including the little holes under the one welch plug) just from stale gas. Add a gas-oil mix who knows how long it was in there and what might be out of whack. Better to start clean and fresh, especially since a full carb kit is only $10-$15 for most Tecumseh engines. If you're going to tear it down anyway, start with a known good setup.
> 
> Just my 2 cents.


Yes I would have to agree with HCBPH on this one. Its your carb, the heart of your engine, if the heart fails, then it all fails. I have a 10hp Tecumseh on mine and rebuilding the carb on mine was the best thing I ever done, despite everyone saying it would be fine. See mine was just all gummed up from sitting for too many years with gas in still in it. Its definitely worth the time and the money and that way you know that if you still have a problem with it after the rebuild, its not the carb. LOL. 

I know not too much that some one else didnt already say but just thought Id chime in anyhow.

Hope you get it going and running good
Cody


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## shawn4545 (Oct 22, 2011)

cableguy said:


> Thanks HCBPH , that's the first thing I did when I got it home, empty out the gas tank. Any ideas where I can get a carb kit for this model. How hard is it to do this? I use to work on my own vehicles back in the days, and I would love to tackle this project.
> Thanks!


No need for carb kit, just put the fresh gas it will clean up by itself.
small engine doctor


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## cableguy (Oct 7, 2011)

*Update*

So I emptied out the oil, it was black and replaced the oil with some new one. I put in fresh gas and started her up. She started fine after 3 cranks, my question is if I put the idle in low (turtle)she shuts off, I have to keep the idle half way or higher for her to remain on. She's idling like up and down, is this the carb??

Thanks


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## cableguy (Oct 7, 2011)

Here are some photos of the plug I found, it looks electrical?


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## cableguy (Oct 7, 2011)

Another photo of plug, Thanks


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## cableguy (Oct 7, 2011)

Engine idles barroom, pa pa barroom pa pa? Is this normal on a snow blower? Should I do the carburetor rebuild?

Thanks,


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## Shryp (Jan 1, 2011)

The rough running sounds like a dirty carb, or possibly an adjustment.

The wire is probably for an optional light.


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## HCBPH (Mar 8, 2011)

*Surging*



Shryp said:


> The rough running sounds like a dirty carb, or possibly an adjustment.


I think Shryp nailed it. It's probably in the carb and if I had to speculate without seeing it, I'd bet one or more of the small holes under the welch plug in the side of the carb are plugged up. If you take that welch plug out, there's little space below the plug and the carb body so be careful or you could damage the carb body. It's not hard to remove if you pierce it and leverage it out with an awl. When you put a replacement in, support the carb directly opposite with a piece of wood (there should be a flat spot on the carb body directly opposite the welch plug, that's where I place the wood to support the carb while putting in the welch plug) and I use a small socket just smaller than the diameter of the plug and tap it in till it's flush with the opening. You can also use a single strand of phone wire and come from the throat side and work it into those 3 tiny holes and see if they're gunked up or not. Some times that's all it takes, just get those tiny holes cleaned out.

If it was me, I'd put a carb kit in and clean everything up squeeky clean (I find brake cleaner works best for me). When reassembling, open the main jet a couple of turns before installing it. While it was apart, I'd clean up the governor linkage too (just don't adjust or move it or it can cause you headaches also). Once the carb is reassembled, start with 1 turn on the main high speed jet (bottom of the carb bowl) and 1 1/2 turns on the midrange jet (side of the carb). Once you have it started, then adjust them as necessary to smooth out the engine.

Good luck


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## kb0nly (Sep 22, 2011)

By your description of the sound its what we call "hunting"

I agree its probably a blocked passage in the carb, she gets a spurt of gas and revs up then trails off and the governor tries to compensate and she revs up again, over and over and over this happens.

Try this though... Start it, when it starts to hunt a bit put the choke on just a bit, does it smooth out with some choke? Let it run til fully warmed up, does it smooth out once warmed up enough to take the choke off?

A lot of these Snow Engines are tuned for cold weather and run like crap when its not cold, once warmed up though it should smooth out. If not time to rebuild the carb!


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## Philscbx (Oct 25, 2011)

cableguy said:


> So I emptied out the oil, it was black and replaced the oil with some new one.
> 
> She started fine after 3 cranks, my question is if I put the idle / she shuts off,
> I have to keep the idle half way or higher for her to remain on.
> ...


Starting with the oil, when it's running good,, change it again hot to really get all the crud out.

It will thank you for years.


As to the idle killing, that's usually the low speed jetting.
It's a bit tricky, but the carb has to come apart.

Give it a good soak, removing the rubber o-rings and any rubber gaskets so they don't get weakened by carb cleaner.

The low speed jet is done a bit different on these, but when the idle mix screw is out, 
squirt carb/or brake cleaner in that hole the needle came out of. 

Up the main jet bore of the carb, it shares the same port as the main jet coming in 
from the side as a very small hole half way up the bore for the main jet that was 
removed to get the bowl off.

Confirm flow with squirts of cleaner through idle screw port.

Yours could be different, but similar.

Air compressor is the main tool to blast out all ports while wet with cleaner.

Re-assemble, should be good as new.


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## Philscbx (Oct 25, 2011)

JUst stumbled on a site for parts, and a troubleshooting section including carb work.
HOW TO REBUILD A TECUMSEH CARBURETOR


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## Shryp (Jan 1, 2011)

Go here and search for tecumseh or carb in his videos:
donyboy73's Channel - YouTube


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## Philscbx (Oct 25, 2011)

*REBUILD Carburetor on 4-5HP Tecumseh*



Shryp said:


> Go here and search for tecumseh or carb in his videos:
> donyboy73's Channel - YouTube


He's does a Good Job.
REBUILD Carburetor on 4-5HP Tecumseh
Still Shot from video.


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