Jonsered Chainsaws

[xl130]

Agreed. I prefer to leave the ignition as it was designed. I just know from experience that chips are easier to source than a condenser.

Ive had a good success rate in the past with cleaning points and carrying on but every now and then a condenser is simply no good anymore.

Does not look like a typical chip install on this saw though. Was wondering where exactly you clip the points wire to eliminate the points on this set up.

 

[xl130]

All good now. No need to deface the ignition assembly. Points cleaned and gapped to .016”.

Fire up off the tank and flooded out. On to the fuel system

 

[Cantdog]

Good job! Now a couple pointers on the fuel system you need to know. First there are two fuel lines, one in the tank and one that runs from the square white vent block under the left side on the carb. The one that runs to the carb is quite special so if it's in decent shape leave it be. It is a different size on either end and rather hard to duplicate. The one in the tank is just regular tubing but if your fuel system is still original there will be what looks like a crimped metal clamp on the upper end and the filter end. These too, are special so don't tear them up. Gently pry them off both hose barbs and when you replace the hose put them on the hose first well away from the ends, slip the hose on the barbs and then slide the stainless clamps back in place.......this is how they work and they will prevent the hose from slipping off the barbs in use. The biggie that stumps many newcomers to the old true Jonsereds is the carb to isolation block gasket. Do not use the diamond shaped gasket that come in all the the kits. Reuse your original if it is decent. If it isn't you can make one or pick up a gasket from your local Husky dealer for a 61, 266, 268, 272. The ones in the kit don't cover the impulse corridor as they are to small. Look it over when you have it apart and you'll see what I mean. Good luck...impressive old school saw.

 

[xl130]

I was trying to figure that fuel line contraption! It’s a check valve?

All the hoses appear to be original. I hate to pull the lines because at least one will rip. The hose for the vent line is the only one that is rotted off at the moment. Does that hose usually have a filter on it? It just runs up towards the clutch without a filter on the end.
Thanks for the tips of the carburetor base gasket. I likely would have missed that one.

 

[Cantdog]

I was trying to figure that fuel line contraption! It’s a check valve?

All the hoses appear to be original. I hate to pull the lines because at least one will rip. The hose for the vent line is the only one that is rotted off at the moment. Does that hose usually have a filter on it? It just runs up towards the clutch without a filter on the end.
Thanks for the tips of the carburetor base gasket. I likely would have missed that one.
View attachment 927045View attachment 927046View attachment 927047View attachment 927048

Yes that line in your first pic is the vent line which attaches to the tank vent shown in your pic. However the correct routing for this line is straight up and over the choke shaft then down under the carb and exit above the clutch . This line and he in tank line are easily exchanged with easily sourced lines....unlike the carb line.

 

[xl130]

Rebuilt the carburetor and replaced the vent line. Kept the fuel lines.

Fired up and died just like before. Seems like it’s choking out or flooding…?

Is there a diaphragm or valve that could be bad in the tank vent assembly?

 

[mogulmasher]

Take end of line off tank and see if you can freely suck in on it. If not still plugged somewhere. Did you flush the sintered brass with brake cleaner or something to make its not clogged?

 

[Cantdog]

Rebuilt the carburetor and replaced the vent line. Kept the fuel lines.

Fired up and died just like before. Seems like it’s choking out or flooding…?

Is there a diaphragm or valve that could be bad in the tank vent assembly?


View attachment 927072View attachment 927073

That fitting you put the vent line on is a check valve more or less......there is a steel ball inside that should rattle when shaken. If it does then all should be well with that.
But your problem sounds more like a metering valve issue if it's getting to much fuel. When at rest the metering lever should sit just flush with the surrounding carb bottom. This may have to be slightly bent to achieve the correct adjustment.

 

[xl130]

Take end of line off tank and see if you can freely suck in on it. If not still plugged somewhere. Did you flush the sintered brass with brake cleaner or something to make its not clogged?

I’ll check it.

 

[xl130]

That fitting you put the vent line on is a check valve more or less......there is a steel ball inside that should rattle when shaken. If it does then all should be well with that.
But your problem sounds more like a metering valve issue if it's getting to much fuel. When at rest the metering lever should sit just flush with the surrounding carb bottom. This may have to be slightly bent to achieve the correct adjustment.

Metering lever is good. Something else going on. I’ll have to have a good look over everything. It will fire up and sputter with the decomp in. Won’t start with the decomp valve closed. And the cord is about a foot long now. Keeps ripping. Damn pull cord needs to be replaced. Old rotten rope doesn’t hold up too well.

 

[Real1shepherd]

https://www.hunker.com/12226169/how-to-test-a-condenser-in-a-small-engine

Did you clean and rebuild the carb?

Kevin

 

[xl130]

https://www.hunker.com/12226169/how-to-test-a-condenser-in-a-small-engine

Did you clean and rebuild the carb?

Kevin

Thanks for the link. Yes carb rebuilt and cleaned. Pressure tested and good to go.
The vent line is clear. I am leaning towards a possible condenser issue.

I have two of these saws. Going to test the second saw and if it runs will swap the condenser.

 

[xl130]

Jonsereds 90 #2 runs after a points cleaning and kill switch removal.

 

[Real1shepherd]

Thanks for the link. Yes carb rebuilt and cleaned. Pressure tested and good to go.
The vent line is clear. I am leaning towards a possible condenser issue.

I have two of these saws. Going to test the second saw and if it runs will swap the condenser.

Lol....I was even going to suggest swapping out condensers from another running saw if you had one.

Like anything else that's subjected to a lot of heat/high current, condensers fail....although not with the regularity that we all thought back in the day.

Wished I had all the condensers back I pitched as a matter of course when renewing points......

If a known good condenser makes no difference and you think you rebuilt the carb properly, there's this....start with the commnets made by 'old fart';
https://www.arboristsite.com/community/threads/testing-ignition-module.197354/

Kevin

 

[edju1958]

Well guys,I got the crank seals for the 49SP in the mail today.I put grease in the seal pocket,on the shaft,& all over the seal (lightly).I started the seal by hand & had it almost halfway in when I put a washer on top of it & then a deep well socket on top of the washer.Tap,tap,tap,& it was in,easy-peasy.I got the clutch side all back together then had to quit for dinner.I'll do the ignition side finishing touches tomorrow.Both seals are in.I can only hope that all seals will go in this easy.This was my first seal replacement.

 

[Real1shepherd]

Well guys,I got the crank seals for the 49SP in the mail today.I put grease in the seal pocket,on the shaft,& all over the seal (lightly).I started the seal by hand & had it almost halfway in when I put a washer on top of it & then a deep well socket on top of the washer.Tap,tap,tap,& it was in,easy-peasy.I got the clutch side all back together then had to quit for dinner.I'll do the ignition side finishing touches tomorrow.Both seals are in.I can only hope that all seals will go in this easy.This was my first seal replacement.

Ed, you really just need a seal driver or socket to match the outer most part of the metal seal(I use tall sockets because of the crank shaft height). Some seals like on the oiler side of some big Huskies, will have to have the inner seal part pushed in so they don't fold.

That's the only way in this application you can go wrong;fold the inner part of the seal so the spring drops out, or drive it in crooked. Sounds like you did fine!

I like to coat the inner seal with whatever it's exposed to...in this case, straight oil from the oil/gas mix I'm using.

Kevin

 

[xl130]

Bad condenser was the problem on Jonsereds 90 #1. Swapped the condenser from the second saw and it fired up and runs strong. Actually sounds great for a saw with a smashed up muffler. Fun learning curve in a new saw brand to me. Definitely a nice addition to my collection. Now to find a condenser for the other saw.

Thanks for your help and guidance! It makes it a whole lot easier to troubleshoot stuff with people that participate in these stickies.

 

[Real1shepherd]

Bad condenser was the problem on Jonsereds 90 #1. Swapped the condenser from the second saw and it fired up and runs strong. Actually sounds great for a saw with a smashed up muffler. Fun learning curve in a new saw brand to me. Definitely a nice addition to my collection. Now to find a condenser for the other saw.

Thanks for your help and guidance! It makes it a whole lot easier to troubleshoot stuff with people that participate in these stickies.

Great! I have worked extensively with the 80/90 series. Great saws, although I plug the 90 decomp because the way I carry the saw running, my cotton gloved knuckles hit the decomp. Easy saw to pull start and so having the decomp for me is of no advantage. Recoil assembly is plenty strong to start the saw without decomp.

Enjoy your 90. And ask away if you have more issues!

If you're really up against the wall and can't find a decent used condenser, let me know.....I'm sure I have one.

Your idle is a little fast.....turn the saw on its side and adjust so it doesn't stall out idling. Otherwise you're wasting gas with the saw idling that fast. An ol' tip from someone who used to have to pack their gas for miles ea day......

Kevin

 

[edju1958]

Trevor,I might have a condenser for you.I'll need you to send me a pic of the old one to match it up.An AS member sent a bunch of condensers & points to me when I bought the 49SP & they don't fit the 49SP..I can post pics of what I have available too.

 

[xl130]

Trevor,I might have a condenser for you.I'll need you to send me a pic of the old one to match it up.An AS member sent a bunch of condensers & points to me when I bought the 49SP & they don't fit the 49SP..I can post pics of what I have available too.