The Forestry Forum

General Forestry => Chainsaws => Topic started by: terizea on April 11, 2017, 07:40:01 AM

Title: chainsaw mount screw
Post by: terizea on April 11, 2017, 07:40:01 AM
have a drop in ms390 for my stihl chainsaw ms290 the 4 screws to the housing /motor were torque at 11 ft/pds instead of inch pds resulting in a stripped screw can anyone resolve this situation??
Title: Re: chainsaw mount screw
Post by: ZeroJunk on April 11, 2017, 08:55:24 AM
11 foot pounds should not have stripped them. Might try to grind out enough room to put a lock nut on top and use a regular 6 MM Allen head screw. Tapping it up to 1/4 SAE may give you a little. Should not be a lot of pressure on it if the other three are tight.
Title: Re: chainsaw mount screw
Post by: terizea on April 11, 2017, 11:58:27 AM
you'r right about the 11ftlbs she torqued at 90inlbs
Title: Re: chainsaw mount screw
Post by: ZeroJunk on April 11, 2017, 12:44:41 PM
90 inch pounds isn't but 7 1/2 foot pounds.
Title: Re: chainsaw mount screw
Post by: terizea on April 12, 2017, 07:16:24 AM
I have a 1/4"-20 tap is this the right one for tapping
Title: Re: chainsaw mount screw
Post by: joe_indi on April 13, 2017, 07:38:37 AM
You cannot do without the metal sleeves that are inserts in the four holes on the engine housing. I don't know whether 6mm screws can pass through the sleeves, today being Maundy Thursday my shop is closed so difficult to confirm this.however, you could used M5 screws and lock nuts.M5 will pass through those sleeves.
Title: Re: chainsaw mount screw
Post by: terizea on April 19, 2017, 05:33:19 AM
 took awhile but got the 6mm bolt it  does go thru sleeve the bolt doesn't go thru the threaded part of cylinder tho,
do I drill out the threaded section on the motor ? and what size drill