Author Topic: Craftsman 4.3 A/VL Idle issues  (Read 414 times)

0 Members and 0 Guests are viewing this topic.

Offline Hoggwood

  • 4 cube
  • **
  • Posts: 64
  • Karma: 17
Craftsman 4.3 A/VL Idle issues
« on: June 20, 2015, 02:13:06 am »
Hi folks,

I am having issues with fuel delivery (I think) while idling.  Saw starts and throttles well.  It will starve out while idling (leaning up) like it is running out of fuel and die.  If I catch it when it begins surging and throttle it, it will respond immediately, settle and return to idle.  I have removed, and rebuilt the fuel cap and venting doesn't seem to be an issue.  After it starves, it will start with a choke and do the same after 20 seconds or so.  I have revamped the entire fuel system, full kit (tried 2 new ones) and had the carb off/apart 1/2 dozen +.  I figured the low circuit might have been plugged.  Pulled the welch.  Spotless. New carb housing/intake block gaskets. 

I have set the L just rich enough to clear hesitation in the throttle.  I want to think it is perhaps simply needing richer L.  But, it will idle really well off of a cold start and suddenly and repeatedly starve out.  I have never experienced this before.   

I am stumped. 

Share on Facebook Share on Twitter


Offline Cut4fun .

  • Administrator
  • Nitro Hotsaw
  • *******
  • Posts: 22115
  • Karma: 550
  • OHIO REDNECK Saw Repair Getter Done
    • Redneck Chainsaw Repair
Re: Craftsman 4.3 A/VL Idle issues
« Reply #1 on: June 20, 2015, 12:07:34 pm »
Craftsman Model  271.358290 on acres.  Echo 701  from reading more on it. Sorry I got nothing good to add to help.

http://www.acresinternet.com/cscc.nsf/ed1d619968136da688256af40002b8f7/e3e3f81f3f49b47e88256dae0051bee5?OpenDocument

REDNECK Saw Repair Getter Done

Offline Eccentric

  • Moderator
  • Nitro Hotsaw
  • *******
  • Posts: 2111
  • Karma: 217
  • Magnesium and Iron.
  • Location: Northern California.
Re: Craftsman 4.3 A/VL Idle issues
« Reply #2 on: June 20, 2015, 02:55:03 pm »
Have you replaced the crank seals and/or done a vac/pres test?  Leaking crank seals can cause the saw to have a weak impulse signal at idle.   That'd cause the pump section of the carb to be weak....................which will allow it to lean out at idle as you describe. 

Seen that several times with Poulan Micros with old crank seals (that seemed to run fine otherwise).  That's a saw series with a 15 mile long fuel line that NEEDS a healthy carb pump section (and a healthy impulse signal).
-Aaron

For older saws:
Tune the H side so that it 4-strokes (burbles) at WOT unloaded and just cleans up when under load.
When you lift cutting load, the saw should immediately revert to 4-stroking.  Fine tune the transition point for the wood you're cutting.

Offline Hoggwood

  • 4 cube
  • **
  • Posts: 64
  • Karma: 17
Re: Craftsman 4.3 A/VL Idle issues
« Reply #3 on: June 20, 2015, 11:47:41 pm »
Thanks guys.  I didn't figure it might be leaking, as it runs really well and idles well in all orientations...until it suddenly and randomly starves.

I really need to buck up and get a vacuum/pressure tester.  One tool at a time.  I see I can get seals through Echo.  Never had to change a seal on an Echo yet.  Then again, I am still pretty new at this.



 

Offline mountainlake

  • 5 cube
  • ***
  • Posts: 119
  • Karma: 21
Re: Craftsman 4.3 A/VL Idle issues
« Reply #4 on: June 21, 2015, 05:02:38 am »
 You didn't mention the fuel line, is it new.  Easy way to check the clutch side seal, take the clutch cover off and spray a little starting fluid around the seal with the engine running, if leaking that will slow down the engine.  Steve

Offline Cut4fun .

  • Administrator
  • Nitro Hotsaw
  • *******
  • Posts: 22115
  • Karma: 550
  • OHIO REDNECK Saw Repair Getter Done
    • Redneck Chainsaw Repair
Re: Craftsman 4.3 A/VL Idle issues
« Reply #5 on: June 21, 2015, 12:59:48 pm »
Thinking this is the craftsman 4.3 I had seen local while back. Could be wrong from memory though. http://chainsawrepair.createaforum.com/echo/craftsman-4-3-avl/msg10317/#msg10317
REDNECK Saw Repair Getter Done

 

Related Topics

  Subject / Started by Replies Last post
3 Replies
529 Views
Last post March 09, 2011, 07:47:49 pm
by hamish
4 Replies
2494 Views
Last post February 20, 2013, 01:47:20 pm
by Cut4fun .
3 Replies
420 Views
Last post February 15, 2013, 04:24:17 pm
by Cut4fun .
6 Replies
130 Views
Last post November 15, 2013, 08:19:21 pm
by Cut4fun
7 Replies
136 Views
Last post March 03, 2014, 07:57:30 pm
by maxmag
17 Replies
715 Views
Last post September 15, 2014, 12:30:02 pm
by 660magnum
1 Replies
288 Views
Last post August 17, 2016, 07:27:27 pm
by Cut4fun .
12 Replies
254 Views
Last post October 14, 2016, 07:03:38 pm
by dannyupsolate
16 Replies
181 Views
Last post September 21, 2017, 07:31:53 am
by jtaxel
1 Replies
126 Views
Last post May 25, 2018, 10:36:47 pm
by farmboy