Go Back   Tech Support Forum > Automotive Center > Small Engines

B&S Lawnmower Engine Hunting and Surging

This is a discussion on B&S Lawnmower Engine Hunting and Surging within the Small Engines forums, part of the Tech Support Forum category. I have a Briggs and Stratton Lawnmower engine (4.5 HP, Model 10H902 Type 0333E2, Code 06011155). The engine ran fine

Closed Thread
Thread Tools Search this Thread
Old 05-25-2009, 03:57 PM   #1
Registered Member
Join Date: May 2009
Posts: 1

I have a Briggs and Stratton Lawnmower engine (4.5 HP, Model 10H902 Type 0333E2, Code 06011155). The engine ran fine the first two years, and for the first two mowings of about 45 minutes each the third year. Starting with the third mowing, the engine speed increased and decreased and used about twice the normal amount of fuel. I replaced the fuel tank and carb assembly and the mower ran fine the rest of last season. This spring it ran fine for the first mowing but towards the end the engine seemed to loose power, but kept running. At the next mowing, I had the same problem as the previous year with the hunting and surging. This time I replaced the diaphragm (no obvious rips) and gasket and the engine ran fine. I previously owned two lawnmowers with B&S engines. Never had a problem with them. Has B&S changed the diaphragm design/material? Perhaps it's loosing its resiliency? I called B&S and they told me I need to use their Fresh Start fuel stabilizer. I find it hard to believe not using it is causing the diaphragm problem. (I put about 20 hours a year on the mower. At the end of the season I let the engine run until it is out of fuel, drain the oil, turn the mower upside down to get remaining fuel out of the tank, then soak up remaining fuel with a paper towel.) Is anyone else experiencing the same problem? Will the use of fuel stabilizer really help? Appreciate any info.
must066 is offline  
Sponsored Links
Old 05-26-2009, 07:19 AM   #2
pat mcgroin's Avatar
Join Date: May 2009
Location: Toledo Oh.
Posts: 2,865
OS: Windows 7 Professional x86 :W7 x 64

My System

Yes stabilizer does help.
I have the same troubles where I live with the snow blowers.
I have found that when I drain the fuel as you stated above I have the same troubles.
Now I use the stabilzer and a little fuel injector cleaner in the gas and and dont drain at the end of the year.
I found that even with running it out of fuel, enough stays in the carb to dry up and turn into varnish.
Starting it up once or twice in the off season helps a bit also.
pat mcgroin is offline  
Old 05-26-2009, 07:39 AM   #3
Moderator Offline
Basementgeek's Avatar
Join Date: Feb 2005
Location: Ohio, USA
Posts: 14,417
OS: XP Pro SP3/Vista Ultimate SP2/Win7 64 bit

I second that motion ! I just pulled at 3 1/2 BS tiller, started on the first pull. It has been sitting in a un heated shed for 9-10 months. It had the same gas it had in it when I put it away.

I use stabilizer all the time.


ASAP member since 2006

Four boxes keep us free: the soap box, the ballot box, the jury box, and the cartridge box.

Basementgeek is offline  
Closed Thread

Thread Tools Search this Thread
Search this Thread:

Advanced Search

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
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Post a Question

» Site Navigation
 > FAQ

All times are GMT -7. The time now is 06:41 AM.

vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
Copyright 2001 - 2015, Tech Support Forum

Windows 7 - Windows XP - Windows Vista - Trojan Removal - Spyware Removal - Virus Removal - Networking - Security - Top Web Hosts


Partially Powered By Products Found At Lampwrights.com