Antique Engines and Old Iron
[Home] - [HELP] - [Forums] - [Groups] - [Classified Ads] - [Subscribe] - [Books] - [Sponsors] -

Go Back   SmokStak > SmokStak® Antique Engine Community > Small Air Cooled Gasoline Engines
Forgot Password? Join Us!

Notices

Small Air Cooled Gasoline Engines Briggs & Stratton, Clinton, Lauson, Maytag, Nelson, Wisconsin and other small air cooled engines. Sub forums for mowers, scooters and powered eqipment.

Small Air Cooled Gasoline Engines

Carburetor spitting gas


this thread has 12 replies and has been viewed 13906 times

Reply
 
Thread Tools Display Modes
  #1  
Old 01-18-2010, 05:36:07 PM
Curtis Curtis is offline
Registered
 
Join Date: Sep 2009
Location: NYC
Posts: 73
Thanks: 0
Thanked 3 Times in 3 Posts
Default Carburetor spitting gas

I started my Ariens st350 3.5 snowblower and let it run first on "slow and then "fast" for about ten minutes. It ran fine then I shut it off. I wanted to make sure the main jet screw under the bowl wasn't running too lean, so I screwed it in and back out two turns. I marked the screw driver so I could put it back it the original position. When I started it up and left the throttle in the slow position it ran fine. When I moved the throttle to the fast position, it started spitting out unburnt gas from the carburetor and popping. I can't figure out what went wrong. Could it be that by moving the main jet screw in and out let dirt in? I took the bowl down last week to look for dirt and it was clean. Also, there is a screw on the left bottom side of the carbuetor. Is this the gas/air screw? I was given the snowblower by a friend who said he started it two years ago and it stalled. He never started it since. When I got it I put gas in it and it started right up. The throttle shaft lever was stuck, so I got it loose and it ran fine. If anyone can shed some light on what went wrong I would appreciate it.
Reply With Quote
Sponsored Links
  #2  
Old 01-18-2010, 06:36:17 PM
Horse Power at 511's Avatar
Horse Power at 511 Horse Power at 511 is offline
Subscriber
 
Join Date: Aug 2007
Location: Fairless Hills, PA, USA
Posts: 299
Thanks: 119
Thanked 90 Times in 65 Posts
Default Re: Carburetor spitting gas

Sounds like its running too rich now, try turning the needle in 1/4 to 1/2 a turn.
Reply With Quote
  #3  
Old 01-18-2010, 06:58:38 PM
Curtis Curtis is offline
Registered
 
Join Date: Sep 2009
Location: NYC
Posts: 73
Thanks: 0
Thanked 3 Times in 3 Posts
Default Re: Carburetor spitting gas

Will do. Thanks.
Reply With Quote
  #4  
Old 01-18-2010, 11:44:32 PM
Andrew Mackey Andrew Mackey is offline
Moderator
 
Join Date: Nov 2004
Location: Rockaway, New Jersey USA
Posts: 14,149
Thanks: 1,992
Thanked 6,767 Times in 4,301 Posts
Exclamation Re: Carburetor spitting gas

Turn in until it seats lightly. Back out 1&1/2 turns. Start engine and let warm set throttle to high, and adjust screw until the engine breaks up, or begins to smoke black. Turn in screw until smoke clears, and or engine just begins to run smooth. You may end up with the needle set between 1 to 2 turns out, each engine is an individual! You want the engine to run slightly rich at high speed, no load, as when loaded, the engine will use all the fuel available to make power. If you set it up too lean, you will end up burning out the exhaust valve.

Double check your valve clearances. If the seats are impacted, clearances disappear, and the valves do not close and open as nescessary. Check your float level and see if the float has any fluid in it. There should be no fluid in the float, and the float seam should be parallel to the bowl mount flange, when the needle is shut.

Andrew
Reply With Quote
  #5  
Old 01-19-2010, 10:01:21 AM
Curtis Curtis is offline
Registered
 
Join Date: Sep 2009
Location: NYC
Posts: 73
Thanks: 0
Thanked 3 Times in 3 Posts
Default Re: Carburetor spitting gas

Thank you.
Reply With Quote
  #6  
Old 01-20-2010, 05:27:40 PM
Curtis Curtis is offline
Registered
 
Join Date: Sep 2009
Location: NYC
Posts: 73
Thanks: 0
Thanked 3 Times in 3 Posts
Default Re: Carburetor spitting gas

I took the carburetor apart, cleaned the main jet screw hole with a thin metal wire, sprayed the carburetor, checked the float bowl for gas (empty) and reassembled the carburetor turning the main jet screw out one and a half turns. I put the carburetor back on the snowblower, started it and got the same popping and spitting out the carburetor. I tried turning the needle in 1/4 to 1/2 a turn but nothng happened. Any further advice would be welcomed.
Reply With Quote
  #7  
Old 01-20-2010, 05:31:25 PM
Craig A's Avatar
Craig A Craig A is offline
Moderator
 
Join Date: Nov 2004
Location: Wisconsin, USA
Posts: 15,480
Thanks: 16,790
Thanked 20,697 Times in 5,986 Posts
Default Re: Carburetor spitting gas

Assuming you can't make it run better by choking it some.......maybe it's a valve problem.......
Reply With Quote
  #8  
Old 01-20-2010, 05:36:05 PM
Motormowers's Avatar
Motormowers Motormowers is offline
Subscriber
 
Join Date: Feb 2005
Location: Hamden, Connecticut, USA
Posts: 2,467
Thanks: 1,275
Thanked 1,222 Times in 636 Posts
Default Re: Carburetor spitting gas

Curtis does it idle OK? Im just wondering how the low speed circuit is in the carb because if its plugged it affects high speed running also. Does your carb have two screws on the side one for idle speed and idle mixture? Some dont have the lower mixture screw but have a brass jet instead that may be clogged. Also make sure you can hear the metering pin clink around when you shake the carb, it keeps fuel from syphoning back to the bowl at idle. Try both mixture screws at 1 turn and make sure you have a new spark plug! I use NGK B2LM in place of the crappy J19LM Champions.
Reply With Quote
  #9  
Old 01-20-2010, 06:39:57 PM
Curtis Curtis is offline
Registered
 
Join Date: Sep 2009
Location: NYC
Posts: 73
Thanks: 0
Thanked 3 Times in 3 Posts
Default Re: Carburetor spitting gas

When I put it back together earlier, I started it on slow throttle with the choke off and it ran fine. When I move the choke setting to off, it started to die out. I tried to move the throttle to fast, but it started popping and spitting. While looking at the carburetor, there is a screw on the left side pointing towards the front of the snowblower. Is this the idle mixture screw? if it is, what would be the setting for it? As far as a valve problem, I wouldn't know.
Reply With Quote
  #10  
Old 01-20-2010, 07:20:18 PM
Motormowers's Avatar
Motormowers Motormowers is offline
Subscriber
 
Join Date: Feb 2005
Location: Hamden, Connecticut, USA
Posts: 2,467
Thanks: 1,275
Thanked 1,222 Times in 636 Posts
Default Re: Carburetor spitting gas

Curtis, if the screw is at the throttle plate then its idle RPM adjust. The screw I mean is lower on the side just above where the float bowl meets the carb. Sounds like your idle cicuit is plugged somewhere if it wont idle off choke. Any pics?
Reply With Quote
  #11  
Old 01-21-2010, 11:13:28 AM
Curtis Curtis is offline
Registered
 
Join Date: Sep 2009
Location: NYC
Posts: 73
Thanks: 0
Thanked 3 Times in 3 Posts
Photo Re: Carburetor spitting gas

I added two pictures of the carburetor:
Attached Thumbnails
Click image for larger version

Name:	Carb-1.jpg
Views:	213
Size:	47.3 KB
ID:	71884   Click image for larger version

Name:	Carb-2.jpg
Views:	182
Size:	48.8 KB
ID:	71885  
Reply With Quote
  #12  
Old 01-21-2010, 01:39:50 PM
Arlie Levy Arlie Levy is offline
Registered
 
Join Date: Dec 2004
Location: Janesville WI. USA
Posts: 870
Thanks: 10
Thanked 385 Times in 275 Posts
Default Re: Carburetor spitting gas

It sounds like the valves don't have the proper clearance. It might start ok when cold and as it warms up is when your problem starts. The valves expands and then there is not enough valve clearance. Arlie
Reply With Quote
  #13  
Old 01-21-2010, 02:03:47 PM
Curtis Curtis is offline
Registered
 
Join Date: Sep 2009
Location: NYC
Posts: 73
Thanks: 0
Thanked 3 Times in 3 Posts
Default Re: Carburetor spitting gas

Is it worth it to have the valves done or just shop for another snowblower? I don't want to dumpalot of money in it and run up a bill to where I could have purchased another one. I just started it awile ago, and it was runningok at low speed. Then as it warmed up, it started popping a little, not much though. When I tried to raise the rpms, I could tell it wanted to spit a pop.
Reply With Quote
Reply

Bookmarks


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

F o r u m Jump

Similar Threads Chosen at Random
Thread Thread Starter F o r u m Replies Last Post
12.5 RJC Carburetor? krc002 Onan Generators 2 11-28-2009 09:39:01 AM
Carburetor Kit help egeschwill Kohler Generators 6 05-24-2008 02:11:05 AM
Carburetor Jerry B Hit & Miss Gas Engine Discussion 1 11-26-2007 04:06:30 PM
Carburetor John Davis Hit & Miss Gas Engine Discussion 3 03-11-2006 09:48:15 AM
B&S Z Carburetor Ralph Leonard Small Air Cooled Gasoline Engines 6 07-18-2005 06:59:27 AM


Use "Ctrl" mouse wheel to change screen size.
All times are GMT -4. The time now is 06:57:14 AM.

Smokstak and Enginads site search!


All use is subject to our TERMS OF SERVICE
SMOKSTAK® is a Registered Trade Mark - A Community of Antique Engine Enthusiasts
Copyright © 2000 - 2019 by Harry Matthews P.O. Box 5612 - Sarasota, FL 34277