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Caution cracked oil line bolt top of valve cover

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FYI 2001 MXC400

while having a new waterpump seal installed, the shop that did the fix, "which ended up leaking the next day again?

noticed that the exterior oil line bolt that mounts on top of the valve cover had cracks through 50% of the bolt?? the bolt has 4 holes for flow of the oil.. and if it should crack all the way? it could ruin a good ride.. the shop said I might have over tightened??You might want to check that bolt next time doing any service up there..

:)

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Good advice about not overtightening banjo bolts. There are several on your bike. They're on either end of that line you mention plus on each end of the 2 brake lines and the clutch line.

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I snapped mine going 2 Newton meters past spec sheet. Be careful

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Torquing fasteners to the proper spec is vitally important.  Most of specified torques are lower than most garage mechanics would guess without using a torque wrench.

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Before engineering school, if it wasn't inside of an engine, it never got torqued. Now I think different.

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57 minutes ago, Repp said:

Before engineering school, if it wasn't inside of an engine, it never got torqued. Now I think different.

Wait until you start designing stuff where peoples lives are at stake and they have trusted you to engineer an item.

There is a shit ton of science and engineering behind fasteners.

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Yea, I witnessed this first-hand last summer. I interned for Caterpillar and was on the design team for the excavator undercarriage stuff. They were having a problem with a newly developed model snapping bolts off between the track links and the shoes. I said, "This is easy guys, use a bigger bolt. The current bolts are right at yield already." My team just laughed and told me to go run numbers on the cost of my idea. What I didn't realize is big companies squeeze every single component down to pennies to save on cost. After a spreadsheet of what my idea would cost, I quickly realized why they laughed. 

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12 hours ago, Repp said:

Yea, I witnessed this first-hand last summer. I interned for Caterpillar and was on the design team for the excavator undercarriage stuff. They were having a problem with a newly developed model snapping bolts off between the track links and the shoes. I said, "This is easy guys, use a bigger bolt. The current bolts are right at yield already." My team just laughed and told me to go run numbers on the cost of my idea. What I didn't realize is big companies squeeze every single component down to pennies to save on cost. After a spreadsheet of what my idea would cost, I quickly realized why they laughed. 

The bolts were right at yield under normal design loads?  If so, that is very poor engineering.  I never design anything without a FOS of at least 2 on non critical things and typically 3-5 on other items.  

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