49sp Jonsereds chainsaw

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Yep that's something to keep track of on some of the older Jonsereds...the cyl base bolts will get loose after a time. Funny too as the gasket on those is real thin and you wouldn't think it would compress enough to allow for loose bolts. One of my nicest 621s came to me as a parts saw with a few pieces missing...when I looked into it I found the reason it was canned was loose cyl bolts and a blown cyl base gasket. The saw had very, very few hours on it. It is now my best running, nicest looking 621....except I am now a bout to start building another 621 completely from NOS parts....still missing a couple parts but have all the big stuff, P&C, carb, oil pump, cases, clutch and recoil covers and handles etc.
 
Welcome to AS! Glad to another Jred back in action, rep to you.

my 49SP was returned from a local mower shop with the message that "it can't be properly tuned.... the bearings are likely to have worn the casing and it's letting in air"...... well they got it part right.... there was air getting in.... but tightening the cylinder head bolts the exhaust manifold and carby manifold got my lil baby purring like a kitten.......

always loved that saw.... after reading this thread.... now I know why


thanks again
 
Beautiful 49SP

49sp looks just fine.

I have a question,
Does anyone of you know dimensions of the crankshaft bearings or what’s the European mark equivalent for those bearings.
Let me explain,
I’ve got 49sp totally disassembled and owner said that originally it had a spark (electric) problem. In one of the shops they told him the crankshaft bearings were worn and both needs to be replaced, but he was not able to find new ones. That is why the chain saw was laying in the box disassembled for a long time. Meanwhile he lost the original bearings and the only trace he could find was a piece of paper where he allegedly wrote what was written on the bearings “DD 38069 TORRINGTON USA”. I was not able to find anything useful on the net so I’m asking you to help me.
When I said European mark, I mean, as an example, “6202ZZ” mark on my Husky 51 bearings.
This is my first post on this site so I’m sorry if I’m not using appropriate terminology.
 
49sp looks just fine.

I have a question,
Does anyone of you know dimensions of the crankshaft bearings or what’s the European mark equivalent for those bearings.
Let me explain,
I’ve got 49sp totally disassembled and owner said that originally it had a spark (electric) problem. In one of the shops they told him the crankshaft bearings were worn and both needs to be replaced, but he was not able to find new ones. That is why the chain saw was laying in the box disassembled for a long time. Meanwhile he lost the original bearings and the only trace he could find was a piece of paper where he allegedly wrote what was written on the bearings “DD 38069 TORRINGTON USA”. I was not able to find anything useful on the net so I’m asking you to help me.
When I said European mark, I mean, as an example, “6202ZZ” mark on my Husky 51 bearings.
This is my first post on this site so I’m sorry if I’m not using appropriate terminology.

The original bearings on most (if not all) 49SPs and 52/52Es etc were SKF 6002 C3 you should be able to take that info to any bearing supply outlet and either get the exact SKF bearings or equivilant..Do not buy the cheapest..I generaly ask for the best quality available. Cost is minimal between high quality and low for a pair of bearings considering the work involved to get to them.
 
Bravo!!!

Cantdog,

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

I wish you all the best.
 
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.
DSCN1025.jpg

DSCN1026.jpg
 
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.
DSCN1025.jpg

DSCN1026.jpg


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...
 
Question on 49SP

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!
 
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
 
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!!
 
Fuel Boils

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?
 
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.
 
Another 49sp heard from

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.
 

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