Thread: 49sp Jonsereds chainsaw

Originally Posted by MikJank

Cantdog,

Thank you very much, that was information I was looking for.

I wish you all the best.

LOL!!! Glad to be of service!!! Good luck and keep that 49SP running!!!

Thanks to this site I just picked up a good deal. I found a Jonsered 49 on craigslist. Due to a google search I found this thread and got all this info I needed to hear. This is my first saw and after a new plug, carb kit and some fresh gas this saw runs better than Ive ever used/borrowed.

Originally Posted by fullclip

Thanks to this site I just picked up a good deal. I found a Jonsered 49 on craigslist. Due to a google search I found this thread and got all this info I needed to hear. This is my first saw and after a new plug, carb kit and some fresh gas this saw runs better than Ive ever used/borrowed.

Welcome to the site.......That is a dandy looking 49SP...good first post...good first saw...all good!!! It looks to be a real low hr example...nice!!!! Take good care of it especially the piston....hard to come by. If it starts to act wierd/different stop and find out why. It can only be a couple different things and pretty much easy to work on. On a saw that old and that nice I'd consider puting in a set of new crank seals right away and get it over with. They harden over time and start to leak slowly......you can tune your way out of it for a while. One way to tell if they are weak is, start the saw, warm it up for a few minutes, with it idling hold it straight out in front of you, turn it on it's left side, turn it on it's right side, hold it pointing straight up, then hold it upside down and then hold it straight down. It should hold it's idle fairly steady. If the seals are new the idle won't change hardly any if at all. With some wear but still functional the idle may slow down or speed up a small amount. If it struggles, revs up or stalls in any position it needs fixin.....seals are only $6-$9... somewhat of a pain to get to but well worth the effort. Plus when you do the flywheel side you can clean up and set the points. Not tryin to scare you or anything and you may well be good to go but thought you should know some of the signs of trouble before it becomes trouble!! Good luck if you have any problems or questions just ask......there's a bunch of guys on here that know their stuff and are always willing to help...

Wow, can't believe I found this forum.

My dad had an old 49SP that he gave to me to get running after the recent hurricane.

Fuel lines were rotted out, should be easy enough fix.

I have one question - there are two lines to the gas tank. One is supply, going into the carburetor, the second has a check valve then goes towards the front of the saw. Is this just a de-pressurization line, or does it come off the exhaust somehow to pressurize the tank?

I can't seem to get fuel to flow through the new lines, even after priming the system by hand. Wondering if there's some mechism I'm missing.

Thanks for any feedback!

Originally Posted by jtagen

Wow, can't believe I found this forum.

My dad had an old 49SP that he gave to me to get running after the recent hurricane.

Fuel lines were rotted out, should be easy enough fix.

I have one question - there are two lines to the gas tank. One is supply, going into the carburetor, the second has a check valve then goes towards the front of the saw. Is this just a de-pressurization line, or does it come off the exhaust somehow to pressurize the tank?

I can't seem to get fuel to flow through the new lines, even after priming the system by hand. Wondering if there's some mechism I'm missing.

Thanks for any feedback!

The one on the left is the tank vent. The other is the fuel supply line. Maybe this will help. Ipl attached.
Shep

Originally Posted by jtagen

Wow, can't believe I found this forum.

My dad had an old 49SP that he gave to me to get running after the recent hurricane.

Fuel lines were rotted out, should be easy enough fix.

I have one question - there are two lines to the gas tank. One is supply, going into the carburetor, the second has a check valve then goes towards the front of the saw. Is this just a de-pressurization line, or does it come off the exhaust somehow to pressurize the tank?

I can't seem to get fuel to flow through the new lines, even after priming the system by hand. Wondering if there's some mechism I'm missing.

Thanks for any feedback!

Welcome to the site. Farmboy is correct...the line that comes out of a fitting is the tank vent..the fitting is also a one way ball type check valve and it doesn't really go anywhere except through the partition. The other line that goes through the top of the tank is the fuel line...this should pass fuel either way. The usual items should be replaced or rebuilt as a matter of course when trying to get a long sitting saw back on line. First do you have spark?? If you do great...if not you will have to pull the flywheel and clean, file and set the points to 0.016" Next replace the fuel line and filter make sure you get the correct size tubing and it should be Tygon not hardward store stuff. Tygon will stand up better/longer to the effects of E-10. Flush the tank completely clean. Next get a carb rebuild kit and throughly dissmantle and clean you carb and install the new kit. Set the "H" &"L" needles one full turn out from just tight. DO NOT over tighten these!!! Pay close attention to the gasket when you remove the carb from the manifold. If it appears to be in good shape...reuse..if not use it as a pattern to cut a new gasket..or go to a Husky dealer and get the same gasket to fit a 61,266,268 272 etc. Do not use the gasket that comes in the kit..it is to small on the outside and will not cover the impulse corridor and the carb will not pump fuel properly. I you need any help just ask or you can search "49SP and 70E Build From Scratch" There are explanations and many pics dealing with everything except rebuilding the carb it self. Good luck!!

Hi - I have a 49SP that I purchased new in 1980 - I still have the sales brochure and exploded parts list if anyone wants a scan.

My saw never did a great deal of work just firewood for a few years and odd fencing work around the farm, and so over all these years it has only had about 4 chains.

It still works fine however I notice that after say 10 minutes it starts to make funny noises and if I look in the fuel tank - the fuel is bubbling as if boiling. I don't remember this happening before ( but I really hardly use it) - should I be concerned about this?

Originally Posted by keychange

Hi - I have a 49SP that I purchased new in 1980 - I still have the sales brochure and exploded parts list if anyone wants a scan.

My saw never did a great deal of work just firewood for a few years and odd fencing work around the farm, and so over all these years it has only had about 4 chains.

It still works fine however I notice that after say 10 minutes it starts to make funny noises and if I look in the fuel tank - the fuel is bubbling as if boiling. I don't remember this happening before ( but I really hardly use it) - should I be concerned about this?

No this is pretty much normal with these saws especially when they get hot. The all mag case conducts the engine heat right into the gas tank and will boil the fuel sometimes. This is one reason why most (all) newer designed saws have a fuel tank that is a seperate piece and usually seperated from the engine case by the AV mounts.

thanks for this thread. I have a family sp49 that looks identical to the one in the photo, it was purchased new in Springfield Ma. in the early 1980's. Who carries the cranks seals? I assume that after all these years they will need replacing. I will try to post a picture.

The crank seals can be had at any industrial bearing/seals place. You need a Double Lipped seal 35MM (OD) X 15MM (ID) by 7mm thick seal. There are some seals that are better than OEM...buy the best you can get..expect to pay $7-$8 each

When I was a kid my grandpa lived about 1/3 of a mile away and I hung out with him alot. I remember helping him when he was cutting wood and he had a homelite saw. One day me and my dad were helping him and I dont remember exactly what happened but his homelite got crushed by a tree. I mean crushed, we cleaned it up with a rake. He replaced it with a Jonsereds 49sp. He used that saw alot until his health went bad and then he passed. He was a wood cutter into his 80's. When he passed my dad got his 49sp and about a year ago I got it. I cleaned it up good and got it running good. I dont use it often because I have my "go to saws" but I enjoy bringing out grandpas saw when I am grilling and need to cut up some smoking wood. I am sure my grandpa would like to see his saw looking all nice and clean, and I think he would enjoy a piece of smoked chicken. I will take some pics of it tommorrow and post them.

Originally Posted by Cantdog

The crank seals can be had at any industrial bearing/seals place. You need a Double Lipped seal 35MM (OD) X 15MM (ID) by 7mm thick seal. There are some seals that are better than OEM...buy the best you can get..expect to pay $7-$8 each

I have had mine since new in 78 and it has been a great workhorse for firewood on tough Australian hardwoods. However recently had some problems with over-heating and dying so I have put a new carbie kit and plug but I can't get it to idle - the low speed jet appears so touchy... then it occurred to me that it could be the crank seals - any thoughts?

Originally Posted by keychange

I have had mine since new in 78 and it has been a great workhorse for firewood on tough Australian hardwoods. However recently had some problems with over-heating and dying so I have put a new carbie kit and plug but I can't get it to idle - the low speed jet appears so touchy... then it occurred to me that it could be the crank seals - any thoughts?

It could be, but it could also be the fuel line. Have you replaced the line recently, if not you should start there.

Originally Posted by keychange

I have had mine since new in 78 and it has been a great workhorse for firewood on tough Australian hardwoods. However recently had some problems with over-heating and dying so I have put a new carbie kit and plug but I can't get it to idle - the low speed jet appears so touchy... then it occurred to me that it could be the crank seals - any thoughts?

Welcome to the site keychange. It is probably time for crank seals anyway...you can only expect to get 34-35 yrs out of a rubber seal, especially in a hot climate. If you have already put a carb kit in did you use the gasket that came in the kit between the carb and the manifold/isolation block? These gaskets do not work on these saws as they are not large enough to cover the impulse corridor. You will either need to reuse the old one (if intact) , make a new one or go to your local Husqvarna dealer and ask for this gasket to fit a 61,66,266,268 etc. If this gasket leaks air/vac you will not pump the correct amount of fuel or hardly any at all plus you now have an air leak as well. I would be sure of this gasket...also be sure the cyl base gasket is intact and the bolts tight...they have a habit of getting loose on these saws and blowing out the gasket, as it is made of very thin paper. Of course if you are set up to perfom a vac/pressure test you can chase down leaks rather quickly.

Originally Posted by PB

It could be, but it could also be the fuel line. Have you replaced the line recently, if not you should start there.

Yep that too!! Don't over look the filter either, whilst you're there....