Husquavarna 346XP stopped Running

[marvlus]

Hello everyone.  This is my first post and I apologize about bringing it up with an issue.   :(  My Husky stopped running a couple of weeks ago when I was cutting a huge log (on the ground).  I was about half way through a cut when it stopped.  Prior to that, I had made 6/7 slices through the log.   There was plenty of gas, but I could not get the thing started again.

I have rebuilt the carb (Walbro HDA) and I can see that gas is getting through it.  Also, I changed the spark plug and I know that it is generating a spark.   Trying to think of any other things that could be wrong.  Any ideas/suggestions would be appreciated! 

[lumberjack48]

Does the saw have any compression ? Welcome to the forum

[marvlus]

Thanks for your response.  I haven't verified that yet.  Being a novice at this, I assume one would have to have a compression tester to confirm that, correct?  Is this something that can be purchased at an auto parts store?

[AdkStihl]

You should be able to tell if there compression when trying to start it.
Although you wont be able to give us a PSI reading without a gauge.
That saw should be blowing at least 150psi IMO.
You didnt accidently run straight gas in it did you?
Impulse line could've popped off, but I highly doubt it.
Weird that it just quit though.
I suppose you could remove the muffler and take a peek at the piston & cylinder through the exhaust port and check for any scoring. If youre not sure what to look for, just take some pictures and post them. I find that this forum isnt all that picture posting friendly so if you'd like, I could give you my email address and you could send them and I'll have a look see?

I know a guy (fellow forum member) who resides in GA. He rebuilds dozens of 346XP every year. I own one that he rebuilt. My go-to saw.
Definetly worth fixing!!

[marvlus]

There is resistance when I pull the starter rope, which would lead me to believe that compression is ok.  I will take the muffler off later today or this week and take a look at piston to see if I can see any scoring.  Thanks for the suggestion!

[beenthere]

marvlus
Welcome to the Forestry Forum.

Don't let anyone scare you away from posting pics, as it is pretty straight forward and not difficult to master.
Here is a primer that will help you set up a gallery and load your pics which will help with the diagnosis.

https://forestryforum.com/board/index.php/topic,61788.0.html

[thecfarm]

By the way,it does look like alot,but after 2-3 times you will whip right through it. If you have trouble ask and we will help. Most times it's something simple that you missed and you wonder how you missed it. Glad to have you here.

[marvlus]

Hello everyone, I finally got around to taking some pictures.  I actually have three pics.  Two are of the piston and the other is of the cylinder.  As you may see , there is some scoring on the piston and inside the cylinder.  Looking at the piston from the top, you can see that the ring is not expanding around the full circumference of the piston.  It almost seems fused where the scoring is present.

I need the experts to tell me if this is significant or not.   I am guessing that this may be my problem. 

   


 


 

[T Welsh]

marvlus, Welcome to the forum. You have discovered your problem with your Husky, to answer your question,YES its significant. You toasted it. It can be rebuilt, but first find out why it burnt in the first place. It sounds as if you are new to this and learning as you go and did a good job of finding out why it wouldnt start. Now before you go ahead and get a new jug and piston. Find out why it siezed so you dont do it again. Check to see if you ran raw gas in it,a cracked intake boot or have the high speed needle adjusted to far in. Just a few cuases of the top of my head. Do not feel bad about toasting a saw, It happens!

 
I toasted this 064 a year ago. It was an old saw and happened exactly the way you discribed your Husky going down. Good luck! Tim

[marvlus]

Tim, 
Thanks for confirming the scoring issues with the cylinder and piston.  I suspect that the reason for the cause of this may be due to a loose intake boot.  The last time I tried starting this (unsuccessfully and after I had rebuilt the carb), I noticed a small bit of gas underneath the boot (near where it connects to the cylinder).

I found on the web, some information about a Service Bulletin for 357XP, 359, 353, 346XP that was sent out 4-5 years, regarding the plastic clamp holding the intake boot to the cylinder.  It spoke about the fact that the plastic clamp could have impaired clamping resulting in leakage in the intake system. 

For those interested, the link that I found is here -> http://www.treeworld.info/f40/rebuilding-346xp-15492.html

Thanks to all that have responded to my inquiry and helping me solve this problem.  I will follow up with a response after I have replaced the cylinder and piston to let you know how it turned out.

You're all a swell group of people! 

[Cut4fun]

I just did a 350 that scored up the same way from the warped plastic clamp. 350 wasn't near as bad as yours, but only had 90psi. I was able to clean piston up, cylinder up and use a new ring. I took and modded old plastic clamp trimmed it up and used a metal intake clamp. All fixed and running great again.

I then took my 346 off the shelf with plastic clamp and put the updated partition and metal clamp on it too. Wasnt going to take the chance anymore scoring up my woods ported top end.

[Cut4fun]

I posted that updated info on this site too.

Here it is again.

For you guys that didnt know about the UPDATE a couple years back.

Service Bulletin for 357XP, 359, 353, 346XP
This service bulletin is not new. I thought that there might be some out there who were not aware of it so here it is. If your saw has a black plastic clamp around the intake right next to the cylinder it is applicable to it. If the clamp is of steel construction then you should be ok.

B0600023
SERVICE

*537 43 88-01*
*compl 537 25 13-02
English 1 (1)

SB, 357 XP, 359, 353, 346 XP,
Partition wall and clamp for intake system,
2006-03

The existing intake system on 357XP, 359,353 and 346XP currently consists of an integrated plastic clamp in the partition wall. As the clamp is made of plastic, there is a risk of deformation. This results in impaired clamping force against the cylinder, which in turn can result in leakage in the intake system. To prevent this from occurring, we have now introduced a metal clamp and a new partition wall.

The new partition wall is made up of polyamide with 30 % fibre glass.
The new clamp is a hardened steel clamp. The new material and the design of the clamp reduce the risk of deformation and the subsequent risk of leakage.

Full replaceability prevails.
Introduced from serial number:
357XP 061100201
359 061100001
353 061100001
346XP 061100001

New part no. Description Excl. part. no. Remark
537 25 13-02 Partition wall, intake, complete New spare part
537 43 88-01 Clamp, intake New spare part

Spare part, partition wall, part number 537 25 13-01, has been discontinued and is replaced by part number 537 25 13-02.