Chainsaw Repair

Husqvarna - Stihl - Poulan - Jonsered - Dolmar chainsaws and more => Husqvarna => Topic started by: g@z on March 25, 2012, 07:31:35 am

Title: 45 Rancher - scored piston
Post by: g@z on March 25, 2012, 07:31:35 am
Hi,

 I filled the 45 up with gas from a container marked with 2 stoke on it, and i think it was just normal gas.  ran the chainsaw for a bit and it stopped. Had it in the local repair place with the muffler off and you an see a vertical line or two in the side of the piston as you rotate it by hand. Guy said it's stuffed. It moves freely it seems and seems to have compression.

 What are my options? New piston? New piston and cylinder? Is that all i need or should other bits be replaced too? If I'm replacing the piston and cylinder is there anything I can do like put a larger piston in it? How easy is it to do yourself or do I need special tools?

Thanks in advance.

Regards,
g@z.
Title: Re: 45 Rancher - scored piston
Post by: Cut4fun . on March 25, 2012, 10:06:35 am
Husky 40 45 IPL  http://s30387.gridserver.com/partsDiagrams/Husqvarna%2040%20and%2045.pdf
Title: Re: 45 Rancher - scored piston
Post by: man of stihl on March 25, 2012, 10:25:42 am
You will have to take the cylinder off. If there is aluminum transfer from the piston on the cylinder walls. Then you can use muriatic acid and sandpaper to remove the transfer. If its gouged above the exhaust port, then you will need a new cylinder. The piston will need a new ring and sometimes a piston can be saved with sandpaper as well. Depends on how bad. Pics would help. I would change the seals and possibly the bearings since all that area will be exposed anyhow.Being a clamshell design, i doubt you can put a bigger top end on it. If you had a 40 i bet the 45 top end would bolt up to that. Old gas/mix is as bad as straight gas IMO. I fixed a trimmer for a guy that needed new fuel lines, well i changed the fuel lines, started it up and it ran for 10 secs and i smoked it. turns out the gas had been in it for a couple years. >:( Now when i fix something i dump the fuel and use my own.
Title: Re: 45 Rancher - scored piston
Post by: g@z on March 31, 2012, 03:34:14 am
Thanks for the reply. I took it apart and it looks bad. There seems to be either pitting ot some sort of delamination of the cylinder wall in this photo: http://i154.photobucket.com/albums/s250/gkwinder/IMG_9315.jpg


In this one, the piston ring seemed to be stuck in one point, and did not twist around the piston. There also seems to be chips out of the edge of the ring (the dark spot on the ring face is not dirt) : http://i154.photobucket.com/albums/s250/gkwinder/IMG_9316.jpg


I'm guessing it's stuffed. New cylinder and piston time. I think I saw some cheap ones on the net, are these cheap chinese copies? Are they any good? Thanks again, cheers.

Regards,
g@z.
Title: Re: 45 Rancher - scored piston
Post by: man of stihl on April 01, 2012, 07:08:48 am
Some aftermarket P&C's are ok and some are pretty rough. If you want something to get you by. Try one of the cheap ones and let us know. ;D It looks to me you have alot of carbon scoring on the cylinder. was this saw running rich or have a real dirty air filter?
Title: Re: 45 Rancher - scored piston
Post by: g@z on April 01, 2012, 08:07:44 am
I think both. Brother in law that borrowed it said he liked to run it rich so it got more oil, and I think the filter is clogged. In fact I only took it to the shop to get a new filter when he saw the marks on the piston. I have the muffler off as it lost a nut and I was getting another one of them as well.

Thanks for the reply. Cheers.

Regards,
g@z.
Title: Re: 45 Rancher - scored piston
Post by: farmboy on April 01, 2012, 09:53:08 am
Ebay seller dandrikop ("The Greek") sells good AM stuff.  I have used P&C kits from Ebay seller kafar85 (Mag Supply, Golf pistons) with good success.  Main advice on Golf DO NOT USE THE CIRCLIPS supplied with piston use OEM clips.  49 P&C kit should work on a 40-45.  http://www.husqvarna.com/ddoc/HUSI/HUSI2001_AAaa/HUSI2001_AAaa__1062425-63.pdf
Shep
Title: Re: 45 Rancher - scored piston
Post by: man of stihl on April 01, 2012, 10:23:20 am
The only 49 p&c i found on ebay is OEM and pricey. http://www.ebay.com/itm/PISTON-CYLINDER-ASSEMBLY-KIT-HUSQVARNA-49-chainsaw-/390085814791?pt=LH_DefaultDomain_0&hash=item5ad2ed2a07 This after market p&c is the small bore 40cc. http://www.ebay.com/itm/HUSQVARNA-40-45-49-CHAINSAW-CYLINDER-PISTON-40mm-/270778187313?pt=LH_DefaultDomain_2&hash=item3f0ba33e31