Chainsaw Repair

Husqvarna - Stihl - Poulan - Jonsered - Dolmar chainsaws and more => Stihl => Topic started by: Cut4fun . on May 19, 2012, 09:24:42 am

Title: Stihl 310
Post by: Cut4fun . on May 19, 2012, 09:24:42 am
 ::) another MS310 in.   Worst case of flooding I have ever seen.

I tilted muffler down fuel poured out. I removed spark plug and pulled over and it was flying out. I took carb off and fuel streamed out of impulse line when pulled over.

Carb appears to have been opened up because gaskets were boogered and  some how metering diaphragm put on 180 degree wrong.

Owner said he had tried to blow carb out. Is there any kind of valve inside this walbro hd 290 310 390 carbs that could have been popped or inverted by him using compressed air?

Pulled carb stops and carb H side was only a 1/4 turn out. Has to have been a factory setting IMO, everything was intact.  :o

Also noticed the saw felt like it had a loose AV  when picking up out of the case. Figured that one out pretty quick.

(http://i59.photobucket.com/albums/g289/doemaster789/200T/ms310002.jpg)
(http://i59.photobucket.com/albums/g289/doemaster789/200T/ms310001.jpg)

Title: Re: Stihl 310
Post by: Cut4fun . on May 19, 2012, 01:47:09 pm
Drained all the gas out. Went through carb, made sure everything is aired and dried out, put in new dry plug. Starts with NO mix in tank and runs till out.

Put mix in tank, go to start with just in on position and instantly floods out no start.  Same thing several different ways. Same results.

Seems like when the mix is added to the tank is when it floods into crankcase. 

 Some how mix getting past needle seat maybe? 

Drain tank, pull through till excess mix out of crankcase, put in dry plug it starts without fuel in tank till runs dry.

Ideas?
Title: Re: Stihl 310
Post by: man of stihl on May 19, 2012, 02:13:50 pm
Did you check your fulcrum needle hight? Or Tank vent may be plugged and pressure in the gas tank forcing too much fuel into carb?
Title: Re: Stihl 310
Post by: Cut4fun . on May 19, 2012, 02:46:50 pm
Yep I went there on all 3. Thanks for running it by me though.

I just pulled a extra carb out of my carb boxes, had 2 to be exact. Runs great with no problems.   Going to offer him my carb.

Still want to know what he could have done to the other old non working  carb. He used air to try and blow it out. Anything in there he could have hurt like valve or something that I cant get to? 
Title: Re: Stihl 310
Post by: man of stihl on May 19, 2012, 02:54:57 pm
Are you going to muffler mod it? :D :D :D
Title: Re: Stihl 310
Post by: Cut4fun . on May 19, 2012, 03:03:29 pm
Guy just wanted it running. So nope.  ;D 

 Still havent got a answer on if he wanted my carb yet.  Carb kit is $13 ( I dont think it will fix problem though and  I dont see anything wrong with kit in it ) and I told him he could have my good carb for $20. Hmmmm I know what I would do.  :)
Title: Re: Stihl 310
Post by: mweba on May 19, 2012, 03:04:34 pm
Had this happen a couple times.  Both instances the needle was not sealing proper and a little tank pressure blows by.  Pull the screen and insert a carb spray tube to test for seal.

Are you going to muffler mod it? :D :D :D

Now that is silly ;)
Title: Re: Stihl 310
Post by: Cut4fun . on May 20, 2012, 05:15:22 pm
Thanks for the idea Mitch.  I couldnt get the other carb to seal off, so he went with my used carb fix.

Just comparison photos. MS310 - 036 Pro

(http://i59.photobucket.com/albums/g289/doemaster789/200T/520fishing2036310013.jpg)
(http://i59.photobucket.com/albums/g289/doemaster789/200T/520fishing2036310012.jpg)
(http://i59.photobucket.com/albums/g289/doemaster789/200T/520fishing2036310001.jpg)
(http://i59.photobucket.com/albums/g289/doemaster789/200T/520fishing2036310004.jpg)
(http://i59.photobucket.com/albums/g289/doemaster789/200T/520fishing2036310007.jpg)