Stripped Plastic screw holes (especially in Echo/Stihl saws), the fix!

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  • / Stripped Plastic screw holes (especially in Echo/Stihl saws), the fix!
I've found my customers, mostly Echo pull starters come loose from the plastic block.

After removing the starter, you can see the brass inserts yanked out with a big hole left.

Depending on the machine, the thickness of the plastic, I've used two options.

For the thicker blocks, I'll pick up some self locking nuts (same machine thread as the stockers) and a long bolt.
Clean the hole real well. Put the new nut on the bolt (grab with a vise grip) and heat with a heat gun as hot as possible.

Now, insert the nut into the block pushing hard. It'll center itself but stop approx. 1/2 way in.

Remove the bolt and take out your Weller soldering gun. Get it good and hot and a medium flat head screw driver.

Put the gun dead center to the nut, the screw driver in the "crutch" of the working end and pull the trigger.
Between the heat, gentle pushing, it will PUSH that nut into the block. Get it just below level. Let it cool in place.

You can push some plastic with the gun over the edges of the nut (with the gun) if you like but you'll find the install better than the original brass inserts.


For thin plastic, again, use the soldering gun (I prefer the thin, single, pointy smaller gun) along with plastic zip ties.

Heat the area (hole) the soldering gun tip and add your zip tie (melting it as you go along) as a filler. Depending on the tip, you can flatten out the surface as need be. You will have to re-drill a new hole as the old one is NOW solid, works on any machine.

Hope this helps...
 

cpurvis

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  • / Stripped Plastic screw holes (especially in Echo/Stihl saws), the fix!
I've never had to repair one of those but it's good to hear from someone who has.

Thanks for the tip!
 

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  • / Stripped Plastic screw holes (especially in Echo/Stihl saws), the fix!
Yep, their commercial machines run very hard, 5 days a week and VERY abused.

With the self locking nut, most times, a good part of the time, the nylon inside remains inside and keeps those machine bolts from loosening..
 

motoman

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  • / Stripped Plastic screw holes (especially in Echo/Stihl saws), the fix!
There are some "cold" epoxy kits available for this kind of fix also. If I can find the book I will cite it.
 

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  • / Stripped Plastic screw holes (especially in Echo/Stihl saws), the fix!
There are some "cold" epoxy kits available for this kind of fix also. If I can find the book I will cite it.

This is much easier, no waiting (well, maybe a minute), and you have STEEL THREADS (like OEM or a heli-coil).

I've probably done 8-10 or so and so far, the workers have NOT been able to yank them out of the block...

The holes left, after the factory brass comes out is a knats hair smaller and makes lining up the new nut a piece of cake...

The only factory threaded hole left, is the top right one. You can somewhat see the "new" nuts set in the block (Echo 355T chain saw) for the pull starter:



This engine is broke down currently to remove a "crankshaft stuffer" that came off while being used:

 
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