Anyone still have a running 70E?

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zuren

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My original reason for joining this forum was to repair my dad's Jon. 70E. It had a bad SEM (ignition) unit that apparently fail often and are nearly impossible to find. I guess he was lucky that it last 20+ yrs. before it died. Links to my threads are here:

http://arboristsite.com/showthread.php?t=33589

I'm sad to report that the used SEM unit that I installed also went bad several months later, so I'm back to searching for a NOS or used but working SEM.

I'm curious to know how many running 70E's are still out there? I also wonder if there are any other lesser known parts sources out there that I may be able to mine? I already have a call into George Blake (motorsag).

Thanks! :cheers:
 
My 70E is still running like a top, don't bring it out that often. It is a heavy sob, but old power is great. Never had to find a parts source before, so I can't help you out in that respect. Good luck in your search.
 
My 70E runs like a raped ape. Pulls a 28" bar. Big and heavy... but cuts great. Started leakin' bar oil though after a day of cuttin'. Leaks just sittin' there.

Other than the leak... it runs like a top.

Sorry, but I have no idea where to find an ignition for it.

Here is an IPL for it...

Gary
 
My 70E runs like a raped ape. Pulls a 28" bar. Big and heavy... but cuts great. Started leakin' bar oil though after a day of cuttin'. Leaks just sittin' there.

Other than the leak... it runs like a top.

Sorry, but I have no idea where to find an ignition for it.

Here is an IPL for it...

Gary

Hello...can you send the email address for the IPL you sent?....I need an IPL for an 80 and would like to se if I can fint it there. thanks
 
70E was electronic ign., from back around 1980 or so.

I think there might have been a plain 70 (without the "E") but not very many.

I imagine that something more modern could be cobbled together and made to work, but it would take a lot of ingenuity. You'd probably have to match a flywheel with very similar weight and balance, find a way to mate it to the crankshaft, and mount the new coil/ign.

The 70E was a great saw, and there are some still surviving. I tried to find an ign for a friend a couple of years ago, emailing a whole bunch of dealers. No luck. I bought him a parts saw on Ebay, but I think we paid too much for it. The ign system is still working, and he has all other parts but a good piston and top cover...none of which will be much use if the second ign system gives up the ghost.
 
i looked ebay and there is one on there flywheel, coil,cylinder head,all wiring,for converting earlier model to later model.:greenchainsaw:
 
Jonsered 70E Plus

I have a nice 70E in my collection that I use and like. Aside from the weight you can't fault the power! I have a 24" bar and full comp chain on it and handles that just fine. I have two more coming from a recent auction plus a 66 and should have extra parts once everything gets checked out. I'm not sure but I think the coil will fit several models. There are those here who can tell more about that. In the meantime here are some pictures of few of my Jonsereds.......Bob
 
i looked ebay and there is one on there flywheel, coil,cylinder head,all wiring,for converting earlier model to later model.:greenchainsaw:

Yeah, I saw that listing. So lets visit this idea (converting from older ignition to "newer") for a second, as it was not something I explored the first time around......so here are a couple questions:


  • [*]Is the coil electronic ignition a more serviceable ignition to have? What I mean is, if I go to the trouble of "upgrading" a 34 yr. old ignition to a 22-27 yr. old ignition and have trouble with it later, will it be something that could be fixed easier or am I in the same boat of having an antique saw with few or no parts available?

    [*]What years did the 70E have the electronic coil ignition? My dad's saw is definitely a pre-1980.

    [*]Would you really need a new cylinder head if you had the newer flywheel, coil and wiring to make the converstion?

Sorry if these questions are elementary, but like I said, it was never suggested to switch the saw over and what the pros/cons of doing so would be.

Thanks!
 
the way i understood the ad was there is 2 version. heres ebay ad.This kit includes all the parts necessary to convert an early model Jonsered 70E to the later model ignition set up. The parts included are: complete flywheel, cylinder head with coil mounting bosses, igition coil, electronic trigger, and wiring. so guess now all ya have to do is figure out which 1 you have.im sure theres some 1 on here can answer your questions.sorry cant be of no help.
 
Which fan wheel you got on that saw? Plastic? Metal? If plastic, you might try taking off the re-coil (starter) check and see if coil can be cleaned. It might be dirty, metal fan wheels used the crank trigger located under the top cover at rear. A small silver box you can usually see it after you take out the air cleaner. Bob
 
I have the 70E coils

The internal magnet SEM units.

When did it stop sparking? The triggers can screw up and also the secondary coils can go bad.

Post some pics so we can get you going.
 
Which fan wheel you got on that saw? Plastic? Metal?

The fan wheel is plastic:

PA170060.jpg


The is what the SEM unit looks like (sitting between shaft and gas cap):

PA170057.jpg


Click this link to see all of the pics I have so I don't eat up more bandwidth:

http://arboristsite.com/showthread.php?t=33589

When I did the original refurbish, the saw had been sitting for about a year. I installed the replacement SEM unit, the saw started, ran and all was blissful. The saw was used intermittently for ~9 months then quit, just like it did before. Now it's been sitting for about a year. My dad said there was no spark, just like before so I'm assuming it is the SEM unit again.

So how does one diagnose a bad SEM vs. bad secondary coils? One complication to this is that I'm in CT, the saw is in MI. I will be back in a couple weeks to deer hunt, so I plan to play with it when I'm back.

Thanks!
 
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