2000 Yam WR400F
Posted December 03, 2009 - 07:36 AM
New here as im a bit stuck...
Im not the most mechanically minded so could do with some help if poss. I have a 2000 WR400F which leaks oil, about 10 or so drips a day.
It is coming from a small nut at the very bottom flat surface of the frame, down on the what looks like a protector of somesort. The nut is only about 10mil and there are 4 of them but only one leaks.
The thread on the nut has gone meaning it wont tighten fully. I dont know if that is the oil resoivoir or if there is a leak further up and its dripping down to there and thats simply the lowest point its coming out?
Anyhelp would be appreciated as this is now my winter bike!
Posted December 03, 2009 - 10:02 AM
as you can see, the bolt is just under a protective cover, it is the most right bolt in this photo.
Closer view, its the bolt at the top of the pic (can see the oil on it)
any help appreciated.
Edited by kyleiom, December 03, 2009 - 10:03 AM.
Posted December 03, 2009 - 10:18 AM
Posted December 03, 2009 - 10:33 AM
All i can see is that it keeps going round when tightened so some thread must have broke.
The main help would be to know if there is a leak further up somewhere and that it the only point where its dropping out or if there is a resoivoir there and the simple fix is to tighten the nut?
Posted December 03, 2009 - 11:14 AM
Posted December 03, 2009 - 11:26 PM
Posted December 04, 2009 - 10:05 AM
Reason I'm asking is that bolt needs to come out about every 5 to 10 hours of ride time since it's one of your oil drain bolts. (yes there are more than one) and if you have never taken it out, I feel very sorry for your poor motor.
If it spins, you've stripped the threads in the case - yes, it can be tapped and heli coiled (mine has been for as long as i've owned the bike) - you might even get a plug one size bigger and can then skip the heli coil.
When you fix it, just be careful you don't overtorque it when doing oil changes.
The washer on mine is nylon and it seems to work fine.
Posted December 04, 2009 - 03:38 PM
Posted December 05, 2009 - 04:49 AM
Is the idea with a bigger bolt just to fit it really tightly?
Posted December 05, 2009 - 07:34 AM
Posted December 07, 2009 - 10:34 PM
Posted December 08, 2009 - 08:06 AM
The idea of an oversized bolt is this:
you tap the hole bigger to accomodate the appropriately oversized bolt and it should fit snug with the right amount of torque as the old smaller bolt.
DO NOT Try to squeeze a bigger bolt into the existing hole, it'll end in an expensive disaster.
The way a heli coil works is the hole is tapped out and a coil is inserted to bring the thread size back down to the original bolt's thread size.