Topic: Engine Case Blt replacement. To flange, or not to flange that is the question...

[brandEn]

I need new upper and lower engine crankcase bolts. They are flange bolts and they are available from Honda but they want Honda Prices. I can get zinc plated, class 10.9, hex bolts and washers for half the price at Bolt Depot. In my usual way of over thinking everything I am wondering, is there any reason I may have overlooked why this can't be done? Is there some crazy reason these need to be Honda Flange bolts?
 

[Old Scrambler]

If the threads are IDENTICAL.......go for it and have a free beer

If you do, I would retorque after a heat cycle

[Fritz]

The flanges act as spring washers and prevent the bolt from becoming loose.
If you use non-flanged bolts, chances are that they would not hold the torque over time, so you'd better use spring washers along with them...

(source: Honda Common Service Manual)

[brandEn]

The flanges act as spring washers and prevent the bolt from becoming loose.
If you use non-flanged bolts, chances are that they would not hold the torque over time, so you'd better use spring washers along with them...

(source: Honda Common Service Manual)

Awesome.
Thanks for that picture.

[MoMo]

The flanges act as spring washers and prevent the bolt from becoming loose.
If you use non-flanged bolts, chances are that they would not hold the torque over time, so you'd better use spring washers along with them...

(source: Honda Common Service Manual)

thanks for that info-I learned something today ...Larry