Jonsereds 49sp leaking fuel & oil

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Found me some all thread and used my existing harmonic balancer puller. Bent the heck out em but it did the job.
The point gap was about 0.010 maybe 0.012. manual calls for 0.04 so that explains low power recently.
Then I noticed the hex bolts were rounded. Thanks a service center I used a couple years ago I'm sure.
So I guess I'm going to take a break today. Maybe tomorrow I'll heat up the bolts and chisel me a Philips end and try and remove them that way.
Cheers
IMG_20200315_154755.jpgIMG_20200315_154812.jpgIMG_20200315_154820.jpg
 
I set mine at 0.016". This is the high side of spec which will give you the longest service life as points always become closer as the wear. Make sure the contacts are flat, come together evenly, each face matches the other perfectly and are not pitted. If you have to dress the contacts be very careful as the actual contact material is quite thin and if you file through that layer the point set is junk. When matching the contacts you can bend the movable contact arm with needle nose plyers to match the stationary contact if need be rather than filing them to match. Also when reassembling condenser/coil/point set electrical connection make sure you get the insulating washers assembled in the correct order or you'll not have spark.
 
I would also add to take notice of how your points plate is adjusted as this is what sets your timing. The 49sp is very easy to do this with as it is simply set to full advance...….in other words the base plate rotated counter clockwise all the way in the adjustment slots like in your pic. Here is a pic of a cleaner set.

As far as getting the screws out, I'd just get on them with a pair of vice grips...…they are spent and will want to be replaced anyway on reassembly.
More than likely someone trying to us a standard size hex key instead of metric was the reason for the damage.

49 SP and 70E Build 082.jpg
 
I'm having trouble removing this last part. It's already jacked up the center shaft on my harmonic balancer puller. I've heated it up with a torch IMG_20200316_184826.jpgand tried to pull. No go! If I am to replace the case gasket I must have this piece (unknown name) removed. Suggestions/advice?
 
I'm having trouble removing this last part. It's already jacked up the center shaft on my harmonic balancer puller. I've heated it up with a torch View attachment 807595and tried to pull. No go! If I am to replace the case gasket I must have this piece (unknown name) removed. Suggestions/advice?
First, thread the nut back on nearly all the way so you have a bigger footprint to push against and don't bugger the threads, then take as much strain as you can get with your puller. Then with a steel hammer strike the puller's center jack screw really hard and square....it will come. Technically you don't HAVE to pull the clutch spyder to replace the gasket.....but....if you're going through all this work you really need to replace both crank seals and the PTO side seal is behind the spyder…..
Again, you could just pull the flywheel side case half and replace the gasket but it's false economy if the 40 year old seal fails and toasts your top end.
These are pics of removing the spyder and crank from a donor saw.....

49 SP and 70E Build 010.jpg49 SP and 70E Build 011.jpg
 
@Cantdog, any dimensions or other info you can offer? Looks real handy and I'll need to fab something to get the flywheel and clutch spyder off to swap seals.

Either one of you offer some insight on bolt/all thread sizes? Metric I assume.

Thanks


Saw Tools 010.jpg
 
I would also add to take notice of how your points plate is adjusted as this is what sets your timing. The 49sp is very easy to do this with as it is simply set to full advance...….in other words the base plate rotated counter clockwise all the way in the adjustment slots like in your pic. Here is a pic of a cleaner set.

As far as getting the screws out, I'd just get on them with a pair of vice grips...…they are spent and will want to be replaced anyway on reassembly.
More than likely someone trying to us a standard size hex key instead of metric was the reason for the damage.

View attachment 807361
The picture looks like it's rotated fully clockwise, not counter clockwise?
 
@Cantdog, any dimensions or other info you can offer? Looks real handy and I'll need to fab something to get the flywheel and clutch spyder off to swap seals.

Either one of you offer some insight on bolt/all thread sizes? Metric I assume.

Thanks


View attachment 807950
Definitely metric but unsure of the size....maybe M4....not much to tell... this started out just to pull 49sp flywheels but evolved as needs changed. The only thing I'd add or change is the addition of a center ram bolt. That way you would not need a number of different length small bolts.....always have to be very careful to have the correct length bolts.....to short you risk pulling the threads out of an alum flywheel...to long you risk destroying your ign system.....especially true on the 66/70E electronic modules.
 
I have been here too. Do yourself a favour right away, get to an air line and blow off all the sawdust and other crud that you can possibly get off. Once you get that Spyder off you will most likely be left with the key stuck in the crank. Most likely it'll be stuck too, and when it comes you will lose it......finding another may not be so simple.
With the guidance you are getting, you will find the whole job MOST satisfying. Fresh crank bearings and seals while you are at it.......
When I split one of mine, I found the case halves did not wan't to separate at the rear handle area......see to it that it comes off the two pins at ends evenly....don't rush.
Turn your balancer puller over, it's stronger up the other way....and flat !
You WILL be delighted with the result !
 
I have been here too. Do yourself a favour right away, get to an air line and blow off all the sawdust and other crud that you can possibly get off. Once you get that Spyder off you will most likely be left with the key stuck in the crank. Most likely it'll be stuck too, and when it comes you will lose it......finding another may not be so simple.
With the guidance you are getting, you will find the whole job MOST satisfying. Fresh crank bearings and seals while you are at it.......
When I split one of mine, I found the case halves did not wan't to separate at the rear handle area......see to it that it comes off the two pins at ends evenly....don't rush.
Turn your balancer puller over, it's stronger up the other way....and flat !
You WILL be delighted with the result !
You may be able to print out gaskets required from the attached. Try it first on A4 paper and check dimension shown on the sheet is correct. If not adjust printer scale until it is, then print direct to gasket paper. This works for me, but by the time it's been across the Atlantic dodging various virus's....who knows. It's a little agricultural, but it works nonetheless !
 

Attachments

  • Jonsereds 49sp crankcase gasket.pdf
    186.4 KB · Views: 10
You may be able to print out gaskets required from the attached. Try it first on A4 paper and check dimension shown on the sheet is correct. If not adjust printer scale until it is, then print direct to gasket paper. This works for me, but by the time it's been across the Atlantic dodging various virus's....who knows. It's a little agricultural, but it works nonetheless !
Another thought... You are going to need some hole punches, leather punch set Ebay or spent 7.62mm cartridge case's and a file or similar to put an edge on mouth for cutting .30/06 .303 etc might do. .223 is too small, but might flare out if stuck. Get the holes done first and check fit before the laborious cutting out. Keep us informed
 
Please look at this video. The crank is a little bent. It's not much but I'd appreciate some expert advice. Between gaskets, sprocket, and time I want to be sure it's still worth it.

And I'm having a heck of a time removing this spider. Just purchased some new all thread (m5 x .8) trashed the last set of threads.
I'll plan to heat it up a little longer this time. I only have propane. I suppose I could buy a bottle of mapp gas for a little more heat.
IMG_20200324_173533.jpg
 
Please look at this video. The crank is a little bent. It's not much but I'd appreciate some expert advice. Between gaskets, sprocket, and time I want to be sure it's still worth it.

And I'm having a heck of a time removing this spider. Just purchased some new all thread (m5 x .8) trashed the last set of threads.
I'll plan to heat it up a little longer this time. I only have propane. I suppose I could buy a bottle of mapp gas for a little more heat.
View attachment 810446

The picture looks like you're off center. Could just be the camera angle.
 
Please look at this video. The crank is a little bent. It's not much but I'd appreciate some expert advice. Between gaskets, sprocket, and time I want to be sure it's still worth it.

And I'm having a heck of a time removing this spider. Just purchased some new all thread (m5 x .8) trashed the last set of threads.
I'll plan to heat it up a little longer this time. I only have propane. I suppose I could buy a bottle of mapp gas for a little more heat.
View attachment 810446


Yep you got problems...…...however your crank is not bent......these cranks do not bend.....they will break but will not be bent. What has happened is you counter weights have gone out of phase......this happens when someone uses a tool like a screwdriver to lock one side of the crank in place to remove either the flywheel or clutch nut. Under this type of strain the crank pin actually shifts/rotates slightly in one or the other of the counter weights. This can be realigned if you know someone with the equipment to do this type of work...….I find it much easier to simply replace with an in phase donor crank from another saw......you're gonna have the cases apart anyway so not a big deal really. You'll notice that you can't achieve a good chain adjustment with your crank in this state. If you adjust to the tight position it will be way loose after a small amount of rotation....if you adjust when it's loose it will be way to tight after some rotation.
 
Yep you got problems...…...however your crank is not bent......these cranks do not bend.....they will break but will not be bent. What has happened is you counter weights have gone out of phase......this happens when someone uses a tool like a screwdriver to lock one side of the crank in place to remove either the flywheel or clutch nut. Under this type of strain the crank pin actually shifts/rotates slightly in one or the other of the counter weights. This can be realigned if you know someone with the equipment to do this type of work...….I find it much easier to simply replace with an in phase donor crank from another saw......you're gonna have the cases apart anyway so not a big deal really. You'll notice that you can't achieve a good chain adjustment with your crank in this state. If you adjust to the tight position it will be way loose after a small amount of rotation....if you adjust when it's loose it will be way to tight after some rotation.
I sure appreciate your advice cantdog, I guess I'm out.
 
I sure appreciate your advice cantdog, I guess I'm out.
If you like the saw here's what I would suggest......scroung around on ebay or chainswr.con for a decent used case with the crank.......you can pretty much tell how much use the saw has had by how much paint is missing......the more intact the paint is the less use it's had as a rule. Many of these saws get parted out when they toast the P&C. This would solve all of your problems without case splitting. Throw a new set of seals in it and move all your parts onto it. These are very easy to work on compared to newer saws. Other than the crank nuts and the two nuts that hold the air box on it only takes two sizes of allen wrenches and a screw driver to take the whole saw apart. Here are three that Brice has for sale presently.....pretty cheap compared to the work you would have to go through to get yours back to the shape these are already in.......I wouldn't hesitate buying either of these....they look to have very light use and I've always had good luck buying from Brice.....

https://www.ebay.com/itm/JONSERED-C...925568?hash=item5202e5b040:g:dXUAAOSw9mpaOAFN
https://www.ebay.com/itm/JONSERED-4...443427?hash=item54543b93a3:g:pyYAAOSwnTdaN-6b
https://www.ebay.com/itm/JONSERED-4...000559?hash=item51fe12deef:g:yNgAAOSwkWNZpxUa
 
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