Chainsaw Repair

WAG Have you looked into  the reeds under the carbs?

I can't see this for all of them, but old clogged fuel filters? Idle may not pull enough gas through.


-•------------------------------------------------------------


Just a home owner that likes the older better made machines

Craftsman 3.7
Echo 290evl
Husqvarna 36

I assume you have a WT carb on yours. The reed is located under the carb. You would have to remove the carb and the box it's mounted in to access the reed. Make sure it's flat and seated and that there is no crap or rust on the reed where it needs to seal against the plastic.

Here's some reading from Walbo.

WT manual
http://www.walbro.com/wp-content/uploads/2016/01/WTseries.pdf

General service manual. Good reading here on how they work and issues

These saws have a LONG fuel line (something like 15") that snakes up and over inside the handle and then down to the carb.  If the pump section of the carb isn't 100% and/or the impulse signal is weak............they'll run like you describe.  You've rebuilt the carbs, so we can focus on the impulse signal.  A leaking reed (grit under the reed, 'tired' reed that won't lay against the carb box surface, etc) can give a weak signal.  Leaking crank seals will too. 

Every Micro I've brought back into service has benefited from crank seal replacement.  They're easy to get and cheap too.  530019059 from any Husky/Poulan parts source (including your local Husky dealer).  Should be around $3-$4 each.  Chicago Rawhide/SKF 4913 will also work, although they'll probably be more expensive than the OEM seals.  Seals on these saws are SUPER easy and quick to change too.  I harp on crank seals a lot..............but in my experience they're a "must replace" when rehabbing an old saw for work.  They're rubber items with a finite life.  They degrade over time just like fuel lines and carb diaphragms....

Thanks all for the excellent responses.  I will order some crank seals and swap them out, it sounds like a good place to start and at that price its not like I am concerned about throwing "good seals" away.  I will check the reed(s) as well.

They are all running Walbro carbs.  Interesting detail- they aren't all identical.  The first difference I noticed was that one or two had three screws for the diaphragm cover, while the other 2 had 4.  Then I noticed one that had a much bigger venturi than the others.  I have already given one saw to a BIL and lent one out, so I can't check those, but I have three carbs in my shop right now and two are of the smaller variety and one is larger. Naturally I put the larger one on the saw I plan on running the most 

Cut4Fun- I will have to get back to you on the L setting.  I tune them to run the best, I rarely count turns; but I know that is the best way to have a discussion like this.