Backfire


  #1  
Old 04-24-11, 12:17 PM
T
Member
Thread Starter
Join Date: Apr 2011
Location: USa
Posts: 146
Received 1 Like on 1 Post
Backfire

I have an older Shindaiwa chain saw. When I try to start it, it backfires every fourth pull or so. Doesn't start. What would you check for that situation?
THANKS!
TomVZ
 
  #2  
Old 04-24-11, 01:20 PM
chandler's Avatar
Banned. Rule And/Or Policy Violation
Join Date: Dec 2005
Location: USA
Posts: 39,964
Likes: 0
Received 9 Likes on 8 Posts
Welcome to the forums! A highly likely scenario is a sheared, or partially sheared key on the crank shaft. It will change the timing just enough to back fire and not run well if at all. Could be rust on the flywheel magnets as well. Have you taken it down below the pull cord yet?
 
  #3  
Old 04-25-11, 06:22 AM
T
Member
Thread Starter
Join Date: Apr 2011
Location: USa
Posts: 146
Received 1 Like on 1 Post
Thanks chandler. No, I was hoping for something much easier! I usually don't go that far into machinery, as I'd likely make things worse. You can't think of anything simpler to check?
 
  #4  
Old 04-25-11, 01:58 PM
chandler's Avatar
Banned. Rule And/Or Policy Violation
Join Date: Dec 2005
Location: USA
Posts: 39,964
Likes: 0
Received 9 Likes on 8 Posts
Backfiring is typically a timing issue, and that's deeper than the fuel cap. It's not that difficult, but I understand if you don't want to go with full heart surgery. Sometimes it is better left to the lawnmower guy to do.
 
  #5  
Old 04-25-11, 07:54 PM
T
Member
Thread Starter
Join Date: Apr 2011
Location: USa
Posts: 146
Received 1 Like on 1 Post
Thanks Chandler. I'll call my small-engine guy.
 
  #6  
Old 04-26-11, 04:58 AM
chandler's Avatar
Banned. Rule And/Or Policy Violation
Join Date: Dec 2005
Location: USA
Posts: 39,964
Likes: 0
Received 9 Likes on 8 Posts
Hey, Tom, I have a Poulan 3400 countervibe bow saw. Simple to change the fuel line, right? I put it all back together and took it to my guy, too. Those lines ran in places where there were no places . Just glad he had the experience to do it.
 
 

Thread Tools
Search this Thread
 
Ask a Question
Question Title:
Description: