Briggs & Stratton Quantum XM 4.5 hp


Old 09-06-07, 08:27 PM
Thread Starter
Join Date: Aug 2007
Posts: 1
Question Briggs & Stratton Quantum XM 4.5 hp

I am having trouble with this motor starting and idling.
It only starts with 3 good pumps of the primer button, puffs blue smoke once, and runs. This is a minor problem.
Once running, it doesn't hit full idle speed but surges up and down. If I physically hold the external component of the throttle plate, it runs smoothly at higher RPMs. I notice there is a spring and small rod connected to either end of the external component of the throttle plate. How can I get it to run smooth? Is it the spring, or is there a vacuum/inertia component that needs fixing?


Sponsored Links
Old 09-06-07, 09:18 PM
cheese's Avatar
Forum Topic Moderator
Join Date: Jul 2001
Location: USA
Posts: 16,815
Sounds to me like you need to clean out the carburetor. Remove the carburetor bowl screw and note the tiny holes in it. Clean these out as well.

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

Thread Tools
Search this Thread
Display Modes