Stihl 090 Early Conrod Problems

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Hi Guys,

Well I spent several weeks trying to find either a Geunine or a Meteor piston 66mm for the 090 but I just couldn't get one. I even emailed Meteor directly in the US. So I decided to buy just a normal cheap aftermarket piston.
The one I purchased is a West branded piston from a supplier here in Australia. It arrived in early January.

And I am not sure if anyone has had this feeling, but i just couldn't bring myself to fitting that type of piston to the 090. Everything in my mind was saying NO. If it wasn't this type/size of chainsaw I might have just used the aftermarket piston.

So after careful looking I decided to use the original piston. There were some very small mark on the skirt of the original piston, and even with my finger nail I could feel them. I also used a brand new set of 66mm Stihl OEM rings, Stihl OEM Conrod big and little end bearings. Plus I rebult the carby as well.

It all went back together perfectly.

However now I do not have spark, it did have spark before the conrod bolt broke. It does have spark sometimes when turning it over but it looks weak.

I will remove the flywheel and just check everything , but my big question is how do I remove the starter cup from the flywheel. I have tried to look it up and I really couldn't find anyting helpful . I even looked and the workshop manual and that wasn't much help either.

Can anyone help. I do not want to force anything .

Cheers

Justin
 

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Probably just super duper snug on the crank threads. Try tapping it or twisting it lightly.

I know exactly what you mean with the piston. Big, expensive saw like that needs factory parts.

Chris B.
 
Hi Guys,

Well I spent several weeks trying to find either a Geunine or a Meteor piston 66mm for the 090 but I just couldn't get one. I even emailed Meteor directly in the US. So I decided to buy just a normal cheap aftermarket piston.
The one I purchased is a West branded piston from a supplier here in Australia. It arrived in early January.

And I am not sure if anyone has had this feeling, but i just couldn't bring myself to fitting that type of piston to the 090. Everything in my mind was saying NO. If it wasn't this type/size of chainsaw I might have just used the aftermarket piston.

So after careful looking I decided to use the original piston. There were some very small mark on the skirt of the original piston, and even with my finger nail I could feel them. I also used a brand new set of 66mm Stihl OEM rings, Stihl OEM Conrod big and little end bearings. Plus I rebult the carby as well.

It all went back together perfectly.

However now I do not have spark, it did have spark before the conrod bolt broke. It does have spark sometimes when turning it over but it looks weak.

I will remove the flywheel and just check everything , but my big question is how do I remove the starter cup from the flywheel. I have tried to look it up and I really couldn't find anyting helpful . I even looked and the workshop manual and that wasn't much help either.

Can anyone help. I do not want to force anything .

Cheers

Justin


Unthread it. Use something like a strap wrench, or oil filter wrench (small) with some old inner tube or something to protect the cup.
Once initial seal is broken and undone a couple of threads you should be able to remove it by hand.
 

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