2003 YZ 450 oil leak

2 replies to this topic
  • holker1

Posted March 02, 2007 - 10:37 AM


the bike is leaking from the oil line that connects to the motor by the shifter. It was a massive leak and i took the line off to find out the dowl had cracked so i bought a new dowl and installed it and it is still leaking very slowly. The bolt is somewhat tight but it feels like i could go tighter but i dont want to overtighten it. Yamahas torque setting for the bolt is 14 ft.lbs. I dont think i got it to 14 ft.lbs, and im scared to go more in fear of stripping it out. Anybody have in ideas on what i should do next?

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  • grayracer513

Posted March 02, 2007 - 11:04 AM


Better go back to the manual again (pg 4-80). That's a 6mm bolt, and the torque is only 7.2 ft/lb.

It should seal at even less than that, though. Check:

> The length of the dowel. There are diffierent ones on the engine with that same diameter. Less than half the dowel should extend out of either the case or the line fitting when it bottoms out. If it's too long, it will keep the fitting from clamping the O-ring.

> The length of the bolt. (see the first item)

> The O-ring. They're cheap, put in a new one.

> The fitting on the line. It's silver brazed to the line, and could be cracked.

  • Butta

Posted March 02, 2007 - 03:08 PM


Grey hit it on the head, as always. My money's on the o-ring......

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