3.5 briggs and stratton rough idle - HobbyTalk
  
HobbyTalk Forum for Diecast Collectors, Modelers, Slot Cars, & Radio Control
Home Forums Photo Album RC TrackFinder Catalog Donation/HobbyTalk Supporter

Welcome to the HobbyTalk forums.

You are currently viewing our boards as a guest which gives you limited access to view most discussions and access our other features. By joining our free community you will have access to post topics, view attachments, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is fast, simple and absolutely free so please, join our community today!

If you have any problems with the registration process or your account login, please contact contact us. Forgotten your password? Click here!

NOTE: Once you register and are logged in this welcome section will no longer be visible.

Go Back   HobbyTalk > Small Engine Repair > Small Engine Repair General Discussion
Register Classifieds Help/TOS Members List Calendar Mark Forums Read

Reply
 
Thread Tools
  #1  
Old 04-28-2008, 02:50 PM
skytronic skytronic is offline
Member

My Photos
 
Join Date: Apr 2008
Posts: 3
Unhappy 3.5 briggs and stratton rough idle

i have a briggs and stratton engine mounted on a lawnmower.
model 10D902
type 0129 B1
code 03021754
starts ok but runs very roughly surging and dropping, can see the governor moving back and forward with surges.
fuel,oil and spark plug ok.hope someone can help
Reply With Quote
  #2  
Old 04-28-2008, 04:07 PM
tommyj3 tommyj3 is offline
Member

My Photos
 
Join Date: Sep 2006
Location: Central Indiana
Posts: 272
Remove and clean carb, then install new carb diaphragm B&S P/N 795083.
Reply With Quote
  #3  
Old 05-01-2008, 12:33 PM
skytronic skytronic is offline
Member

My Photos
 
Join Date: Apr 2008
Posts: 3
hi tommyj3 removed and cleaned carb fitted new diaphragm but its still idling roughly any ather sugestions. thanks
Reply With Quote
  #4  
Old 05-01-2008, 01:05 PM
tommyj3 tommyj3 is offline
Member

My Photos
 
Join Date: Sep 2006
Location: Central Indiana
Posts: 272
What I would do is put about 2 ozs of fuel additive in a full tank of gas. Start engine let it run, and see if the additive cleans any crud that may still be in the carb. I personally use Sea Foam Fuel Additive for this.
Reply With Quote
  #5  
Old 05-01-2008, 03:09 PM
dawgpile dawgpile is offline
Member

My Photos
 
Join Date: Apr 2008
Posts: 144
When you removed carb and cleaned it, did you check the fuel inlet pipe and clean it as well? I'm not sure if this has the screen on the bottom of the pipe or on the side, but in either case, a dirty inlet can starve the engine and cause it to 'hunt'.
Reply With Quote
  #6  
Old 05-02-2008, 07:36 AM
skytronic skytronic is offline
Member

My Photos
 
Join Date: Apr 2008
Posts: 3
hi,yes cleaned the gauze at the bottom of inlet pipe.took it apart again and cleaned blew air through jet and body ,still idling roughly ,racing and slowing down.
Reply With Quote
  #7  
Old 05-02-2008, 10:59 AM
pyro_maniac69 pyro_maniac69 is offline
Elder Statesman

My Photos
 
Join Date: Aug 2007
Posts: 813
did you put the gasket and diaphram on the correct way? if you didn't put those on than it will not run coreectly
Reply With Quote
  #8  
Old 05-02-2008, 11:11 AM
ajp ajp is offline
Member

My Photos
 
Join Date: Apr 2008
Posts: 8
rough running

Quote:
Originally Posted by pyro_maniac69 View Post
did you put the gasket and diaphram on the correct way? if you didn't put those on than it will not run coreectly
remove and check spark plug. It could be fouled partially. After cleaning check gap. REinstall. if still rough then the mixture screw may be at fault. Use a screwdriver to first adjust lower screw 1/2 turn either in or out. If problem still exist go to top screw and turn 1/2 turn inand out. Your problem can be old gas also. If all these dont correct the problem them it could be the points. check back later...
Reply With Quote
  #9  
Old 05-02-2008, 09:45 PM
pyro_maniac69 pyro_maniac69 is offline
Elder Statesman

My Photos
 
Join Date: Aug 2007
Posts: 813
oh, I'm sorry, I didnt look at the model number, I was unaware it was an older style diaphram carb
Reply With Quote
  #10  
Old 05-02-2008, 10:08 PM
30yearTech's Avatar
30yearTech 30yearTech is offline
HobbyTalk Supporter

My Photos
 
Join Date: Sep 2006
Location: Central Texas
Posts: 5,626
Quote:
Originally Posted by pyro_maniac69 View Post
oh, I'm sorry, I didnt look at the model number, I was unaware it was an older style diaphram carb
It's not that old, and there are no adjustments on this carburetor skytronic, so don't look for any. It is possible that old gas can cause a problem, your engine has no points either solid state ignition, a partially sheared flywheel key can cause a rough running engine too.

Pyro, this is a pulsa prime carburetor, your inquiry about gasket and diaphragm orientation is a valid question.

Last edited by 30yearTech; 05-03-2008 at 12:03 AM.. Reason: update
Reply With Quote
  #11  
Old 05-03-2008, 12:21 AM
pyro_maniac69 pyro_maniac69 is offline
Elder Statesman

My Photos
 
Join Date: Aug 2007
Posts: 813
ah ok, I saw the 10D model number and thought that it might have been an older model series

thanks 30year
Reply With Quote
  #12  
Old 05-03-2008, 12:22 AM
pyro_maniac69 pyro_maniac69 is offline
Elder Statesman

My Photos
 
Join Date: Aug 2007
Posts: 813
I REALLY need partsmart on my computer or something
Reply With Quote
  #13  
Old 05-03-2008, 12:39 AM
30yearTech's Avatar
30yearTech 30yearTech is offline
HobbyTalk Supporter

My Photos
 
Join Date: Sep 2006
Location: Central Texas
Posts: 5,626
Quote:
Originally Posted by pyro_maniac69 View Post
I REALLY need partsmart on my computer or something
You can find parts look up and various sites on line, like partstree.com, jackssmallengine.com and of course briggsandstratton.com, may be a little slow if you have dial-up but otherwise pretty useful for looking up or at IPL's
Reply With Quote
  #14  
Old 05-19-2008, 08:01 PM
oldstick oldstick is offline
New Member

My Photos
 
Join Date: May 2008
Posts: 2
Very similar question

I think I have the same basic motor and carb. Mine is Model 9D902. This is a small Murray mower with the "throttle free" carb. Someone left behind when I moved in and looks to be used very little.

Prime it and it cranks first try and runs like a scalded dog for 5 minutes then slowly cuts off like when they run out of gas. Prime again and runs great for another few minutes and repeat.

Odd thing is it ran for 20 or 30 solid minutes the other day while I was weeding a rough, steep drainage ditch area. Tilting up/down/sideways pretty much the whole time. Then moved back to the level yard and off it goes after a few minutes.

This has got to be a fairly simple problem. Anyone know what is going on?
Reply With Quote
  #15  
Old 05-19-2008, 08:38 PM
30yearTech's Avatar
30yearTech 30yearTech is offline
HobbyTalk Supporter

My Photos
 
Join Date: Sep 2006
Location: Central Texas
Posts: 5,626
Fuel pump diaphragm may not be pumping fuel into the pickup area, operating on an incline and fuel can make it's way to the pickup without the diaphragm pumping it there. Probably a new diaphragm in the carburetor will take care of the problem.
Reply With Quote

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools

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

Forum Jump


Featured Sponsor
You Can Sponsor
A HobbyTalk Forum


HobbyTalk® Sponsors
Diecast
CScollectibles
Collectables Corner
DieCast Alley
Global Diecast Direct
Milezone
Mini-Motors Inc
Scoomer
The Toy Peddler
Toy Car Aution
Models
MegaHobby
Modeler’s Brand
ParaGrafix Modeling Systems
Radio Control
BeachRC.com
B-Fast RC
Dirt Cheap RC
Discount RC Tires
Irrgang Racing Service
Lefthander RC
MaxAmps.com
RCTV Live
SMC Racing
Speedzone
Thunder Racing
Tekin
Trend Times
TQ Racing
Windtunnel Racing
Slot Cars
AFX Racing
Scoomer
Slot Magazine
Sponsored Events

Become a
HobbyTalk® Supporter

Advertise on HobbyTalk®



Powered by vBulletin®
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
All times are GMT -4. The time now is 12:58 AM.
HobbyTalk® is a Registered Trademark of HobbyTalk Ltd.
All other logos and trademarks on this site are property of their respective owner.
Copyright (c) 1997-2012 HobbyTalk Ltd. No use without permission.