Jonsered Chainsaws

[Real1shepherd]

Upgraded air cleaner ....
https://www.ebay.com/itm/2351220719...zCCk5zuRd6&var=&widget_ver=artemis&media=COPY

No appreciable gains there, that's been long proven. They're ugly and owners tend to misplace or throw away the OE NLA air filter covers.

Kevin

 

[palebird71]

Flywheel is tapered friction fit....so locks with the Woodruff key and locknut (30-35Nm). Fuel pump in the Tilly carb....do you mean the carb to manifold gasket?

Kevin

Actually what I meant was a method to keep the crank from rotating as you loosen/ tighten the flywheel nut.
No there is a pump mounted right on top of tank beside the carb. Has an impulse line and two fuel lines. That gasket between pump and tank opening.

 

[Real1shepherd]

Actually what I meant was a method to keep the crank from rotating as you loosen/ tighten the flywheel nut.
No there is a pump mounted right on top of tank beside the carb. Has an impulse line and two fuel lines. That gasket between pump and tank opening.

NO....that's not a "pump" but a vent box(with a check valve) for the tank and fuel feed to your carb. Learn your saw and nomenclature. The fuel pump is inside the Tilly as I said originally. The impulse channel is in the intake manifold under the carb-to-manifold gasket. As far as a gasket there at the vent/fuel supply box...just make one. Would take less time than to hunt one down that is NLA.

As far as stopping the crank from moving while you tighten the flywheel nut. Different ways to do it. Some use a piston stop that's either metal(*cringe*) or plastic. Some use nylon rope shoved through the spark plug hole. Me, I always use a cut piece of rubber V-belt that will fit through the spark plug hole.

Kevin

 

[palebird71]

I don't know. There is a rubber gasket/seal that was underneath what you call the vent box. Looks like a pump to me. Worked on lots of high performance 2 strokes snowmobiles, boats and they all use impulse activated pumps. But whatever. The question was " do these interchange with Husqvarna part numbers, specifically this gasket?" Not a longwinded beratement. This why I don't like these sites so much..too many "experts".As far as stopping the crank from moving I have used those methods. So there is no neat setup like the McCulloch 1-52? Great. Thanks a bunch.

 

[Cantdog]

I don't know. There is a rubber gasket/seal that was underneath what you call the vent box. Looks like a pump to me. Worked on lots of high performance 2 strokes snowmobiles, boats and they all use impulse activated pumps. But whatever. The question was " do these interchange with Husqvarna part numbers, specifically this gasket?" Not a longwinded beratement. This why I don't like these sites so much..too many "experts".As far as stopping the crank from moving I have used those methods. So there is no neat setup like the McCulloch 1-52? Great. Thanks a bunch.

Hey......Kevin gave you nothing but correct information. What you are calling a "pump" is not just as he said. You may know something about boats and snowmobiles but from your pics it is not actually one of these. And from your response you don't know chit about Jonsereds chainsaws and just as obviously have no interest in learning anything from those that do. Since you wanted to know about interchange parts to Husky.........absolutely nothing other than perhaps a sparkplug, and a tilly carb kit.....nothing.....not even fuel lines....true Jonsereds have nothing what-so-ever in common with Husqvarna.......other than both being Swedish.

For the record I also own a 1962 1-52 Mac and have since I was 13 years old.......like for 56+ years of ownership......my BIL bought it new. I hold the Jonsereds 621 about 30 rungs up the ladder of advancement from that slow, loud , heavy old Mac....but perhaps I'm also just another "expert" sayin' chit......

 

[Real1shepherd]

I don't know. There is a rubber gasket/seal that was underneath what you call the vent box. Looks like a pump to me. Worked on lots of high performance 2 strokes snowmobiles, boats and they all use impulse activated pumps. But whatever. The question was " do these interchange with Husqvarna part numbers, specifically this gasket?" Not a longwinded beratement. This why I don't like these sites so much..too many "experts".As far as stopping the crank from moving I have used those methods. So there is no neat setup like the McCulloch 1-52? Great. Thanks a bunch.

You can call it whatever you want, but it's not a pump and you seem reluctant to learn that. This is the most pleasant/helpful chainsaw thread you will ever participate in and has been for yrs. If you wanna upset the apple cart that's your business. You wanna argue with people, go to the Husky thread...plenty of takers there.

The 621 is a true Jonsereds and quite different than Huskies of the same vintage. Learn your Jonsereds history. They were an independent company until Electrolux Group AB bought them around 1978. They also bought out Husky a bit later and so the Husky/Jonsered connection started around 1982 or so with Jonsereds being built at the Partner assembly plant since 1978....also purchased by Electrolux Group AB. As Robin said, the only similarity between Husky and Jonsereds back then is that they were both Swedish saws. No parts interchanging with Husky.

Yes, I know the gasket is rubber....you buy gas-rated rubber gasket material of the same thickness. I buy mine from Amazon because of the convenience. No "longwinded beratement" intended, just trying to explain something that you don't seem to accept.

Kevin

 

[hitchhikersthumb]

Hey there. I had posted a question a few days ago about differentiating between a 920 and an 830. Only got one reply and it was a guess, but I don't know how to use this site very well yet, so it may have never been seen. Anyway, I acquired the saw and measured the bore with a rolled up piece of newspaper. Looks like right at 2 1/8 with my precision instrument, so that would mean 920?

The interesting part is that, as I was taking off the 24" bar, it seemed the sprocket was rather large. Turns out it has 9 teeth/pins/whatever you want to call them. I thought 8 was about as big as one would want to go on an 80-something cc saw with a shorter bar. Were the 920s just that torqy that you could use a 9 pin with a 24" bar?

Also, I'm planning on using it but it's been sitting for many years. It's in good shape, starts and idles nicley. but I'm wondering if there's anything specific to these that I should check/replace before running it hard. I've heard parts are harder to come by so I'd like to avoid breaking something right off the bat. Thanks!

 

[heimannm]

I am rather fond of McCulloch chainsaws, but the Jonsereds 621 is indeed way above any 80cc front tank McCulloch saw; that was my first upgrade ever in the fall of 1981 when I replaced the sad old Mac with a brand new end of the run 621. I used it hard for 26 + years as my main firewood saw with 16 and 24" bars. The upgrade included sprocket nose bars, an automatic chain oiler, and Carlton chain and File-O-Plates...and changed the way I harvested my wood. A new saw included a tool specifically designed to lock the clutch to facilitate changing the sprocket from 8T (16" bar) to 7T (24" bar) which would also lock the crankshaft if you had to remove the flywheel for any reason.





I still have remnants of that original saw including the hand guard and spark plug cover in the model I have in the display today.



Mark

 

[Cantdog]

I am rather fond of McCulloch chainsaws, but the Jonsereds 621 is indeed way above any 80cc front tank McCulloch saw; that was my first upgrade ever in the fall of 1981 when I replaced the sad old Mac with a brand new end of the run 621. I used it hard for 26 + years as my main firewood saw with 16 and 24" bars. The upgrade included sprocket nose bars, an automatic chain oiler, and Carlton chain and File-O-Plates...and changed the way I harvested my wood. A new saw included a tool specifically designed to lock the clutch to facilitate changing the sprocket from 8T (16" bar) to 7T (24" bar) which would also lock the crankshaft if you had to remove the flywheel for any reason.

View attachment 1104429

View attachment 1104430

I still have remnants of that original saw including the hand guard and spark plug cover in the model I have in the display today.

View attachment 1104433

Mark

Excellent Mark!! I never knew of this tool.....learn something new every day!!! Any chance you could post a pic of it in use so I understand how it works......may well work on other models too. Looks easy enough to replicate just from you pic. Funny I've never even seen one on ebay.....of course if you didn't know what it was for it would be a hard thing to list!

 

[Cantdog]

Hey there. I had posted a question a few days ago about differentiating between a 920 and an 830. Only got one reply and it was a guess, but I don't know how to use this site very well yet, so it may have never been seen. Anyway, I acquired the saw and measured the bore with a rolled up piece of newspaper. Looks like right at 2 1/8 with my precision instrument, so that would mean 920?

The interesting part is that, as I was taking off the 24" bar, it seemed the sprocket was rather large. Turns out it has 9 teeth/pins/whatever you want to call them. I thought 8 was about as big as one would want to go on an 80-something cc saw with a shorter bar. Were the 920s just that torqy that you could use a 9 pin with a 24" bar?

Also, I'm planning on using it but it's been sitting for many years. It's in good shape, starts and idles nicley. but I'm wondering if there's anything specific to these that I should check/replace before running it hard. I've heard parts are harder to come by so I'd like to avoid breaking something right off the bat. Thanks!

Sorry I really don't have much experience in the 8XX or 9XX series except for the 910. I think ModifiedMark answered your question in the main forum. If someone else doesn't help you here you might PM him......I know he has quite a bit of time and knowledge in this series.

 

[hitchhikersthumb]

Sorry I really don't have much experience in the 8XX or 9XX series except for the 910. I think ModifiedMark answered your question in the main forum. If someone else doesn't help you here you might PM him......I know he has quite a bit of time and knowledge in this series.

Thanks, I was thinking about PMing him about the Jonny and Heimannm about Mac parts but didn't want to PM people without their permission. Not sure how it works here and I want to be respectful

 

[Real1shepherd]

Hey there. I had posted a question a few days ago about differentiating between a 920 and an 830. Only got one reply and it was a guess, but I don't know how to use this site very well yet, so it may have never been seen. Anyway, I acquired the saw and measured the bore with a rolled up piece of newspaper. Looks like right at 2 1/8 with my precision instrument, so that would mean 920?

The interesting part is that, as I was taking off the 24" bar, it seemed the sprocket was rather large. Turns out it has 9 teeth/pins/whatever you want to call them. I thought 8 was about as big as one would want to go on an 80-something cc saw with a shorter bar. Were the 920s just that torqy that you could use a 9 pin with a 24" bar?

Also, I'm planning on using it but it's been sitting for many years. It's in good shape, starts and idles nicley. but I'm wondering if there's anything specific to these that I should check/replace before running it hard. I've heard parts are harder to come by so I'd like to avoid breaking something right off the bat. Thanks!

The 920 was an Electrolux Group AB saw and as such, had much Partner influence. The 930/930 Super was starting to be Husky influenced. Not sure I'd run the 9 tooth, but the 8 tooth would be OK depending on what you're trying to do with the saw.

Bore should be 54mm to be a 920. 830 would be 52mm. I'm not following the newspaper trick, perhaps you can find something to measure more accurately? You'll lose the entire saw if there's a leak in your crank seals...run too lean. I'd replace both of them due to age and all the fuel/oil lines. Then a vacuum/pressure test on the saw itself by blanking off the muffler and intake port. Protecting your vintage saw that way, then move FWD to whatever you want to do with it. If it were me and the saw had a dubious history of maintenance, I'd USC the carb and put in a fresh kit.

Kevin

 

[Real1shepherd]

Excellent Mark!! I never knew of this tool.....learn something new every day!!! Any chance you could post a pic of it in use so I understand how it works......may well work on other models too. Looks easy enough to replicate just from you pic. Funny I've never even seen one on ebay.....of course if you didn't know what it was for it would be a hard thing to list!

Oh hell yeah....let's see it work!!

Kevin

 

[hitchhikersthumb]

The 920 was an Electrolux Group AB saw and as such, had much Partner influence. The 930/930 Super was starting to be Husky influenced. Not sure I'd run the 9 tooth, but the 8 tooth would be OK depending on what you're trying to do with the saw.

Bore should be 54mm to be a 920. 830 would be 52mm. I'm not following the newspaper trick, perhaps you can find something to measure more accurately? You'll lose the entire saw if there's a leak in your crank seals...run too lean. I'd replace both of them due to age and all the fuel/oil lines. Then a vacuum/pressure test on the saw itself by blanking off the muffler and intake port. Protecting your vintage saw that way, then move FWD to whatever you want to do with it. If it were me and the saw had a dubious history of maintenance, I'd USC the carb and put in a fresh kit.

Kevin

I read on here about using a plastic drinking straw to measure the bore by removing the muffler and sticking the straw in to the back of the cylinder then pulling the starter cord until the piston creases the straw. Pull the straw out and measure to where the crease is and there's your bore size. I'm on vacation and the only thing I had handy was newspaper so I rolled it up like a straw and it seemed to serve the same purpose.

Is there someone on here I should talk to about parts like crank seals and such? Or is that just a google/ebay thing? I'm planning on doing the same general overhaul on a PM850 and was planning on asking Heimannm if he sold things like av mounts and crank seals or if I should find them elsewhere. I appreciate the info!

 

[heimannm]

Did you ever wonder why the clutch drum on the 621 and related saws had those two small slot openings?



The tool fits through that opening and into the clutch. Notice the 8T sprocket since I have the saw fit with a 16" bar in the display, .058 gauge by the way...



Crankshaft is locked.



The tool is made from 12 gauge (.100" thick) steel but I've made them from14 gauge as well. It is not a tool that will see hard, daily use.

I do have crankshaft seals and AV mounts for the SP/PM type McCulloch saws, you can send a PM or "conversation" by clicking on that envelope looking icon in the upper right hand corner of the screen.

Mark

 

[Cantdog]

Ahhhh....Thanks Mark taking the time to set that up and photo it. I must admit it took me a minute or two to figure out how it locked the clutch itself not jut the drum, even with the pics. But I get it now. Nice!! Thanks again for sharing!!!

 

[heimannm]

The top photo shows the slot on the left aligned with the gap in the clutch shoes, that would be the normal orientation for removing the left hand threaded nut. Rotate the clutch a bit and switch side when you are putting it back together.

Mark

 

[Cantdog]

Yep....makes perfect sense........Thanks again!!! Now to see how many of my Jreds stll have slotted drums......

 

[RedneckChainsawRepair]

Did you ever wonder why the clutch drum on the 621 and related saws had those two small slot openings?

View attachment 1104641

The tool fits through that opening and into the clutch. Notice the 8T sprocket since I have the saw fit with a 16" bar in the display, .058 gauge by the way...

View attachment 1104639

Crankshaft is locked.

View attachment 1104640

The tool is made from 12 gauge (.100" thick) steel but I've made them from14 gauge as well. It is not a tool that will see hard, daily use.

I do have crankshaft seals and AV mounts for the SP/PM type McCulloch saws, you can send a PM or "conversation" by clicking on that envelope looking icon in the upper right hand corner of the screen.

Mark

Thats cool.

I learned something like that years back working on partners which also jred 490 590 etc.

I learned the trick of holding the topend still through the crankcase with a hex wrench years ago. Didnt have to use a piston stop or rope trick through the sparkplug hole anymore.

 

[Real1shepherd]

I read on here about using a plastic drinking straw to measure the bore by removing the muffler and sticking the straw in to the back of the cylinder then pulling the starter cord until the piston creases the straw. Pull the straw out and measure to where the crease is and there's your bore size. I'm on vacation and the only thing I had handy was newspaper so I rolled it up like a straw and it seemed to serve the same purpose.

Is there someone on here I should talk to about parts like crank seals and such? Or is that just a google/ebay thing? I'm planning on doing the same general overhaul on a PM850 and was planning on asking Heimannm if he sold things like av mounts and crank seals or if I should find them elsewhere. I appreciate the info!

15x30x7mm is the seal size and try to find a 'double lip' style. I buy my hoses at a local Honda outdoor equipment place.

Seals are everywhere on the Net and in bearing houses if you have one. You'll dredge the world for AV mounts unless someone is hoarding them.

Kevin