Jonsered Chainsaws

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Not every day can you still snag a rare bargain off e-bay anymore......

But I did this morning.......found two El Motor (EM) OEM NOS #587 329 602 ign modules delivered, sales tax included for $28.49 for the pair.

These fit any of the 625, 630, 670/ Champs and the equivilant Husky 2 series with the one piece ign .

I have needed a couple of these for some time but couldn't bring myself to buy the cheap China versions or the the super expenive OEM ones.

Priced these on partstree this morning........sit down now.........ready? $106.99......EACH plus shipping and sales tax!!!!
 
Slightly off-topic but I value the opinion of those of you mechanically inclined on here that may not see posts from other threads.

I recently acquired a Stihl MS462 that came with a stripped out plug hole, for real real cheap money. Naturally never having fixed one myself I searched and asked the question on a different sub-forum, and searched YT.

On here, almost universally spring helicoils were pooh-poohed as a choice, and time-serts and sav-a-thread were praised. Then I looked at YT and Rich Dougan says spring heli-coils are a-ok and he has two videos on the subject.

What do you guys think, are spring heli-coils a sufficient repair or do I need to spring for a time-sert (sav-a-thread isn't really a choice since it only comes in M14x1.25, the OEM plug is m10x1.0).
 
Slightly off-topic but I value the opinion of those of you mechanically inclined on here that may not see posts from other threads.

I recently acquired a Stihl MS462 that came with a stripped out plug hole, for real real cheap money. Naturally never having fixed one myself I searched and asked the question on a different sub-forum, and searched YT.

On here, almost universally spring helicoils were pooh-poohed as a choice, and time-serts and sav-a-thread were praised. Then I looked at YT and Rich Dougan says spring heli-coils are a-ok and he has two videos on the subject.

What do you guys think, are spring heli-coils a sufficient repair or do I need to spring for a time-sert (sav-a-thread isn't really a choice since it only comes in M14x1.25, the OEM plug is m10x1.0).
That's about the only time that a Helicoil may have the advantage....in that it won't unscrew back out. That's the issue with a regular steel insert like Time-Sert.....most folks try to put them in with regular red Loctite. Trouble is that the head temp gets so hot if you try to pull out a hot plug, you may unscrew the thread insert along with it.

But Loctite does make a product, 2620, that will handle the heat. The Helicoil will work fine in this application because it won't back out. The trouble is if you should happen to cross-thread that Helicoil.....good luck getting that sucker out. Rich has talked before about dissimilar metals and the problems you can get into with spark plug inserts. He's looking at it from a shop perspective....if he sends it out, will it come back in with the same issue or worse?

Time-Serts are probably the best insert system out there, but they require proprietary taps and tools. You could easily spend $80 to do one hole. I endorse EZ-LOK inserts. They go the extra distance to make sure you can install with common taps and tools. I've never had one fail and have been using them for over a decade. They even have them with US outside threads and metric inside threads.....so if you just have a US tap set you're good to go. I have shaped old screwdrivers to fit their inserts for installation. They sell an install tool, but most of the stores I buy them from just carry the inserts, because they couldn't sell the tools.

EZ-LOK even has thin wall inserts which come in really handy when you don't have much meat to work with.....

Kevin
 
That's about the only time that a Helicoil may have the advantage....in that it won't unscrew back out. That's the issue with a regular steel insert like Time-Sert.....most folks try to put them in with regular red Loctite. Trouble is that the head temp gets so hot if you try to pull out a hot plug, you may unscrew the thread insert along with it.

But Loctite does make a product, 2620, that will handle the heat. The Helicoil will work fine in this application because it won't back out. The trouble is if you should happen to cross-thread that Helicoil.....good luck getting that sucker out. Rich has talked before about dissimilar metals and the problems you can get into with spark plug inserts. He's looking at it from a shop perspective....if he sends it out, will it come back in with the same issue or worse?

Kevin
Interesting, Time-sert's own instructions for washer type plugs specify not using thread locker. They only require it for taper plugs. The Loctite they sell and recommend for using on tape plugs is Loctite 266. That 2620 is EXPENSIVE from a quick Google search.

The varied opinions about helicoil vs inserts are very interesting, Donny Walker also prefers sav-a-thread estimating he has a 90% retention in the threads he repairs using that method. After talking to another user here who is known for doing weld/drill/retap repairs on cylinders on the forum also recommend I give heli-coil a try, especially seeing that it's a smaller m10x1.0 plug. I'm gonna give that a try first.
 
Interesting, Time-sert's own instructions for washer type plugs specify not using thread locker. They only require it for taper plugs. The Loctite they sell and recommend for using on tape plugs is Loctite 266. That 2620 is EXPENSIVE from a quick Google search.

The varied opinions about helicoil vs inserts are very interesting, Donny Walker also prefers sav-a-thread estimating he has a 90% retention in the threads he repairs using that method. After talking to another user here who is known for doing weld/drill/retap repairs on cylinders on the forum also recommend I give heli-coil a try, especially seeing that it's a smaller m10x1.0 plug. I'm gonna give that a try first.
Interesting point on tapered plugs versus washer plugs. I think you'll be fine with a Helicoil in this example. I know it won't back out.

Kevin
 
Thanks Kevin.

1) Do you have any preference on brand of helicoil? There's so much out there (PowerCoil®, Heli-coil®, Perma-Coil®, E-Z Coil®, and then a million chinese iterations floating around on Amazon)
2) does the helicoil have to be the same length as the reach of the plug or can I be a little shorter (say 10mm vs. 12.7mm)?
 
If I was gonna use one, I'd probably stay with the original; Heli-coil. Everyone tried to make one 'as good', but better(?), haven't heard that.

As far as length, I'd want it to match the thread length of the original hole. Sticking way into the combustion chamber, no.....being short on length of the original threads, no. Probably not a big deal, but the goal is always to approximate the original in most repairs.....unless there is a design issue.

Kevin
 
That Save-A-Thread system by Helicoil looks really slick and Walker shows how to use it in a vid. I'd sure use the high-heat Loctite I recommended above.

Ahhh, but you said that system only comes in 14mm and you need 10mm.....my bad.

Kevin
Yea, this M10x1 sizing makes things a bit tricky, a similar m10x1 sav-a-thread kit would've been huge.

Although I did find in my internet journey this kit using inserts from a German saw shop that looked intriguing, at a much lower cost than time-sert. Not much info on how it secured to the cylinder though.
 
Yea, this M10x1 sizing makes things a bit tricky, a similar m10x1 sav-a-thread kit would've been huge.

Although I did find in my internet journey this kit using inserts from a German saw shop that looked intriguing, at a much lower cost than time-sert. Not much info on how it secured to the cylinder though.
Yeah, be nice if they had a vid on using it. I search YouTube....nada.:reading:

Kevin
 
In this video, Rich Dougan shows the use of HeliCoil to repair spark plug threads and he mentions that aluminum shavings from the repair that end up in the cylinder are not a concern. I'm...skeptical, but intrigued.

I would get the shavings out at any cost. Granted they're soft, but still. Get the piston close to TDC, do the grease trick and a piece of paper shop towel stuffed in there first. Everyone blows the remnants out with compressed air. Why push metal bits IN instead of OUT? I use a very strong vacuum...my best shop vac after I've swabbed the hole with a few Q-tips damp(not dripping) with solvent.

Kevin
 
If were me.......I'd just pull the cyl......just 4 more bolts. Put the cyl in a bench vise so it is totally stable and you aren't chasing a rolling chainsaw around the bench while trying to bore a staight hole Then the shavings are no worry...
I've considered it. But this Stihl 462, is not like the 451 I've been working on what seems like forever now. It's a puzzle just to take it apart, SO MANY PIECES just to get to the cylinder.
 
I've considered it. But this Stihl 462, is not like the 451 I've been working on what seems like forever now. It's a puzzle just to take it apart, SO MANY PIECES just to get to the cylinder.
And that is exactly why I don't own ANY Stihl Chainsaws...........but they will come apart and go back together again......I've done it....hated every minute of it too!!!! Overly complicated just because they could......
 
And that is exactly why I don't own ANY Stihl Chainsaws...........but they will come apart and go back together again......I've done it....hated every minute of it too!!!! Overly complicated just because they could......
Wait!!......That is not completely true. I came back from a week at my camp on the island once and found two orphans on my home front doorstep........and 041AV and an 021.......they are behind the back burner of project saws......I've done nothing to or with them except bring them from home to the far back corner of the shop........hoping someone needs them more than me......
 
I've considered it. But this Stihl 462, is not like the 451 I've been working on what seems like forever now. It's a puzzle just to take it apart, SO MANY PIECES just to get to the cylinder.
That's why I didn't suggest pulling the jug....heard that about Stihls....a real puzzle to take apart. Can't say 'I hate them' because I never had one, nor will I.

Just out of curiosity, I watched them come apart on YouTube and I'm thinking 'What were they thinking when they designed these saws?' Donyboy has many vids of them coming apart.....hope he charges appropriately.

Kevin
 
And that is exactly why I don't own ANY Stihl Chainsaws...........but they will come apart and go back together again......I've done it....hated every minute of it too!!!! Overly complicated just because they could......

That's why I didn't suggest pulling the jug....heard that about Stihls....a real puzzle to take apart. Can't say 'I hate them' because I never had one, nor will I.

Just out of curiosity, I watched them come apart on YouTube and I'm thinking 'What were they thinking when they designed these saws?' Donyboy has many vids of them coming apart.....hope he charges appropriately.

Kevin
Like @Cantdog said, they do come apart, and then you put them back together. I obtained a service manual to try to avoid any issues, and that has actually been good read (just for the general troubleshooting 2-strokes and standard shop procedures).

I was thinking I would expose the cylinder as much as possible taking everything around it off, then use clamps to secure the saw to my bench, keep it stable and such. I got a piloted tap to help avoid tapping it in crooked. Grease + shop towel + solvent + vacuum.
 
Like @Cantdog said, they do come apart, and then you put them back together. I obtained a service manual to try to avoid any issues, and that has actually been good read (just for the general troubleshooting 2-strokes and standard shop procedures).

I was thinking I would expose the cylinder as much as possible taking everything around it off, then use clamps to secure the saw to my bench, keep it stable and such. I got a piloted tap to help avoid tapping it in crooked. Grease + shop towel + solvent + vacuum.
As in any shop, the more methodical you are, the better it turns out. Let others laugh at the extremes you go to, but you'll never be on the short end of the stick that way!:cheers:

Kevin
 

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