Briggs & Stratton Model 406777 - replacement bolts

JohnnyAce

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  • / Briggs & Stratton Model 406777 - replacement bolts
Started some work last year on the motor on my L120, didn't keep track of the bolts to reattach the intake on both sides.... Grrr, just get a ziploc baggie... anyway everything is basically a 10mm head but a 1/4-20 bolt seems to fit really well. I'd like to keep everything oem but not if I have to buy $4 to $7 bolts. Any suggestions.
 

StarTech

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  • / Briggs & Stratton Model 406777 - replacement bolts
Well welcome to our world of specialize screws. This why shops have to keep secure placement of removed fasteners. We don't like over paying for these either. Even as a dealer these are high to get.

Double check the threading as these should SAE screws with SAE hex. IF metric only fits and the 3/8 doesn't then they are likely threaded metric.

First the hex should be a 3/8" as that is what they normally used on these engine with the flange head screws. On top of that these screw heads have a T30 slot which makes easier access to the screws for removal and installation. They also a Red loctite patch so they don't vibrate out.

But I have not found any after market that both the T30 and 3/8" hex that are Flanged. I have to add Blue Loctite to the threads as the Red I have is too strong for standard hand tool removal.

699816
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The lowest price per I found is
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But if threads are 1/4-20 then you should able it in a flange screw locally, just won't have the T30 slot.
 

Auto Doc's

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Check the drawers or box where you put your tools at. Likely put them away for "safe keeping" (keeps you from finding them when you need them.) LOL
 
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