Head gasket, waterpump seals or What?

2 replies to this topic
  • YZ Yankee

Posted August 31, 2015 - 07:25 AM


My 01 YZ426 has been progessively harder to start.
Thought I was due for valve adjustments.
My last ride was just a couple easy laps at the track. Now the bike will not start.
I found oil mixed with my coolant when I drained the radiator.
No coolant in the oil.
Coolant was found in the exhaust pipe, like a half cup worth.
There is oily residue where the exhaust pipe meets the cylinder head, a little at the valve cover above that and that "plug" that's in the cylinder head .
When I was prepping the bike for a ride, I did notice the coolant was very low, then I topped it off. This is a pic of my coolant.

Oh, also the spark plug was wet..looked like coolant.

So what do you think?

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Edited by YZ Yankee, August 31, 2015 - 07:27 AM.

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  • grayracer513

Posted August 31, 2015 - 09:40 AM


Head gasket.  

  • YZ Yankee

Posted September 05, 2015 - 08:42 PM


I'm running into some issues as I attempt to pull the head off.
1. The bolt in the photo is catching on somehing inside the head. It will not come out. Any suggestions on what might be the problem and solution. 1441513849218.jpg
2. The #7 nut, toward the intake side of the cylinder is in accessible. You can't get a socket in there. An open end will strip it.
Thought about pulling the entire engine, the pulling the cylinder and head off as one piece. Then I'd have the room to get to it .
Will that work?
Is there really only 2 bolts holding the cylinder to the lower case?
3. Look at photo 3. Is that a gouge made by the valve? That valve clearance measured .17mm. Specs are .10mm to .15mm.
Thanks for your help.

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