Bringing back a 621 Jonsereds

[SawTroll]

Yes Niko I did mean 220 lbs. Thanks! I will edit that. I will get you the numbers later today when I go to the shop.

This was the compression just after the first start, having burnt the assembly lube off.

View attachment 516820

My impression is that is perfectly normal on a healthy 621 - and I have seen much higher numbers posted. It also was one of the first models to have a Nikasil coated bore, as far as I know.

One of the reasons for the high compression likely is the domed piston.

 

[Cantdog]

Niko here are the numbers;

The saw in this thread is 872162

The saw with the Total bar is 853290

The saw with the gray Windsor bar is 902520


And yes I would consider 220 to be pretty average for a 621 in good condition.....the nice thing is that they have such a large diameter starter pulley that even with these compression figures they are very easy to pull over.

 

[SawTroll]

Thanks!

I understand you are not a member on the Swedish based Chainsaw collectors site that is linked up at Acres site. Would it be OK if I posted the numbers (+ a couple of your pictures) in the (older) Jonsereds serial number thread there? Most of the numbers posted there so far are in the 3xx xxx range...

 

[Stihl 041S]

What an awesome study on Saw Philosophy.......

 

[tbone75]

No not quite yet.....another issue to deal with now that it starts and runs OK. Someone did something and I can't understand why.

The front bar stud was cranked way to far into the case......so far in fact I could only get about a turn and a half on the threads and as I pondered that I noticed that what I had taken for really nice bars nuts were indeed flawed. Someone had scrunched, mechanically I presume, three equidistant flats on the nut. Kind of a reverse knurling so that the nut size was reduced enough to create an interference fit to the point where it overcame the threads in the case. So I had to double nut and heat the case to get the stud back out. Cleaned both threads thoroughly with acetone and set at the correct depth and locked with some really heavy duty red locktite (that someone gave me LOL!!). Then replaced both bar nuts with used stock ones. The offending nut is the one on the left.

View attachment 516809

Looks way to even to be done by man ? Seen some nuts like that , but never on a saw ? LOL

 

[tbone75]

Yes Niko I did mean 220 lbs. Thanks! I will edit that. I will get you the numbers later today when I go to the shop.

This was the compression just after the first start, having burnt the assembly lube off.

View attachment 516820

That baby gonna run !!!

 

[Cantdog]

Thanks!

I understand you are not a member on the Swedish based Chainsaw collectors site that is linked up at Acres site. Would it be OK if I posted the numbers (+ a couple of your pictures) in the (older) Jonsereds serial number thread there? Most of the numbers posted there so far are in the 3xx xxx range...

Not sure.....I think I joined Magnus's site years ago.....that may not be what you are talking about. but Yes you may repost anything helpful. This info should be made available to those that have an interest in these saws....after all,the original company is gone.......we are the only ones who care......and our numbers are probably slowly becoming less as time goes by.....sad but true.....so, Niko feel free to rewpost anything I have ever posted concerning the Jonsereds line...with the understanding that I am not the omnipotent one......there well could be error in some information.......Oh wait......that is why you are my editor...LOL!!!

 

[Cantdog]

That baby gonna run !!!

Well it did run.......took it up to Mikey's woodpile yesterday and put it to her. Was very hot......about 90 degree 'Merican......and I wailed it onto this saw .....it cut good out of the box but as time went by it got noticeably stronger......but at the 1/4 left mark it started having problems......it failed after a big cut.....just kinda died out.....then would not restart. Put it away.......I think it just got to hot breaking in a new piston......it was boiling the gas in the tank rather frantically.......we'll see tomorrow......again.....this is what makes a good thread.......not so much the build but the trouble shooting after the build. Anyone can build a saw and have it run.....but the joy is to build a saw and find out why it doesn't run......they say we learn by our mistakes.......I should be getting quite a bit of knowledge by now!!!!

 

[Stihl 041S]

Well it did run.......took it up to Mikey's woodpile yesterday and put it to her. Was very hot......about 90 degree 'Merican......and I wailed it onto this saw .....it cut good out of the box but as time went by it got noticeably stronger......but at the 1/4 left mark it started having problems......it failed after a big cut.....just kinda died out.....then would not restart. Put it away.......I think it just got to hot breaking in a new piston......it was boiling the gas in the tank rather frantically.......we'll see tomorrow......again.....this is what makes a good thread.......not so much the build but the trouble shooting after the build. Anyone can build a saw and have it run.....but the joy is to build a saw and find out why it doesn't run......they say we learn by our mistakes.......I should be getting quite a bit of knowledge by now!!!!

Troubleshooting Guide included.

How is Mikey doin?

 

[Toyboy]

No not quite yet.....another issue to deal with now that it starts and runs OK. Someone did something and I can't understand why.

The front bar stud was cranked way to far into the case......so far in fact I could only get about a turn and a half on the threads and as I pondered that I noticed that what I had taken for really nice bars nuts were indeed flawed. Someone had scrunched, mechanically I presume, three equidistant flats on the nut. Kind of a reverse knurling so that the nut size was reduced enough to create an interference fit to the point where it overcame the threads in the case. So I had to double nut and heat the case to get the stud back out. Cleaned both threads thoroughly with acetone and set at the correct depth and locked with some really heavy duty red locktite (that someone gave me LOL!!). Then replaced both bar nuts with used stock ones. The offending nut is the one on the left.

View attachment 516809

That nut on the left is one of self locking style. The other style I'm familiar with is the nylock type.

 

[Cantdog]

Troubleshooting Guide included.

How is Mikey doin?

Mikey's doing pretty good......he finished the cutting the other day with an old beat 028.....20 minutes or so....I expect he was hurting yesterday but he has to keep pushing the limits or he will lose mobility. I was going back to the woodpile yesterday but garden work in the morning and then the bride's cousins all want the have a lobster bake on the shore starting around 2 pm and continued with many beverages, bugs an 5 guitars and much singing until darkness overtook us. No saw work yesterday.....gonna try the 621 in the wood again today after I (hopefully) fix an outboard this morning.....That's where I was headed when we spoke yesterday afternoon.....call got dropped I guess cause it got real quiet on my end!!

 

[Cantdog]

That nut on the left is one of self locking style. The other style I'm familiar with is the nylock type.

It odd that they are the same style nut with flanges but one is a lock nut the other not. Needless to say they both went in the circular file.

 

[SawTroll]

Not sure.....I think I joined Magnus's site years ago.....that may not be what you are talking about. but Yes you may repost anything helpful. This info should be made available to those that have an interest in these saws....after all,the original company is gone.......we are the only ones who care......and our numbers are probably slowly becoming less as time goes by.....sad but true.....so, Niko feel free to rewpost anything I have ever posted concerning the Jonsereds line...with the understanding that I am not the omnipotent one......there well could be error in some information.......Oh wait......that is why you are my editor...LOL!!!

Thanks!

Btw, I can't find you on the member list of Magnus' site, at least not as Cantdog. Is it possible that you used a different user name at that site?

 

[Cantdog]

Thanks!

Btw, I can't find you on the member list of Magnus' site, at least not as Cantdog. Is it possible that you used a different user name at that site?

Hmmm Well I would be on as Cantdog......perhaps then I did not join....thought I did, but I guess I must have been there as a guest.

 

[tbone75]

Just happen to think I never got my 621 running right , seemed like it needed seals ? But gonna be up to someone else to fix it soon . Lots of red is leaving the shelf . Not sure if I will just fleabay them or what yet ? Stihl not sure what or if I will keep any of them ? Most likely all gonna go .

 

[Cantdog]

I guess I found my "dying out" problem........pinhole in the fuel line....right at the carb end. Moved the spring clamp down and cut the line back...lost about 1/2" of line but still reached fine. Would have replaced it but those are rather special lines and I don't have any NOS ones of those. Pressure and vac tested both fuel lines. The line in the tank looked and tested fine but while I was there I replaced it and the filter too. That tank was pretty rough inside...the filter had already accumulated some debris. Pulled the carb down to make sure it was clean inside. Starts and seems to run normal again....which it definitely was not doing earlier this morning. Will test in the woodpile first opportunity.

 

[tbone75]

I guess I found my "dying out" problem........pinhole in the fuel line....right at the carb end. Moved the spring clamp down and cut the line back...lost about 1/2" of line but still reached fine. Would have replaced it but those are rather special lines and I don't have any NOS ones of those. Pressure and vac tested both fuel lines. The line in the tank looked and tested fine but while I was there I replaced it and the filter too. That tank was pretty rough inside...the filter had already accumulated some debris. Pulled the carb down to make sure it was clean inside. Starts and seems to run normal again....which it definitely was not doing earlier this morning. Will test in the woodpile first opportunity.

Kinda thinking you may have ready to cut some wood now .

 

[Cantdog]

OK!!! The 621 has passed it's test with flying colors!!! Finished Mikey's 8 cord pile this afternoon. The old thing ran perfectly.....ran it pretty hard....never threatened to stall...returned to idle quickly and smoothly. Throw a very light touch up on the chain......and Thursday I'll be picking up a few more thread inserts so I can redo the upper left hand recoil bolt and this project will have reached it's desired conclusion. I forget from time to time how much I love running a 621......generally I grab something a little faster...a little lighter...a little newer. But you know...in the end I don't think I get done any sooner....the 621 is an incredibly steady wood cutting tool...even "Mikey liked it".....and misguided as he may be, he likes nothing but Stihls and Fords....silly man.....Mikey says "Hey" Unc...


Just goes to show......the old 621 can still "Get 'er Done"

 

[Stihl 041S]

Hell of a tale!!!!

 

[Cantdog]

You know me Unc......there's gotta be a story!!!!!


But I sense it's not over yet...LOL!!