YZ timing- I think I screwed up . . . ?


5 replies to this topic
  • Ripmeister

Posted April 18, 2006 - 07:41 PM

#1

I thought I did all the research - I read all the threads I could find, I got instructions from Thumperfaq.com, I printed pages from my shop manual, but I'm still stumped with the YZ timing.

Keep in mind I'm a weekend mechanic only - this is probably one of the most complicated things I've done with an engine. Laugh if you will . . .

Anyway, I got to the step of removing the timing chain tensioner - removed. then I realized the flywheels did not have the little puchmark at the top of them and the E was upside down on the right side and the I on the left. I had aligned the H symbol in the sight window and thought I was at TDC, but apparently I was at the top of the compression stroke, not the top of the exhaust stroke.

SO without reinstalling the timing chain tensioner I rotated the engine trying to get it to the top of the exhaust stroke. Did I screw up the timing or is that only if I rotate the engine after removing the cam tower? The reason I ask is that after finding TDC (as I thought) the exhaust cam has the little punchmark at the top but the intake cam has it at about 3 o'clock.
:thumbsup:

Do I have to re-time from scratch? If not, how do I get both sprockets to have the punch marks on the top? Do I just keep rotating until they line up?

I really appreciate your help. Maybe I have to find a mechanic who does house calls, but I'd rather be embarrassed in front of a computer screen than with a guy who looks at me like I'm some dumbazz which I guess I might be.

  • jbrooks26

Posted April 18, 2006 - 08:43 PM

#2

It sounds like you were just 180 degrees out when you started. This is not a problem as long as you did not have the chain off yet. Just turn the engine until you get the lobes facing away from each other and go from there. If you did take the chain off already, it is still not a problem. With the exhaust cam removed, hold the chain away from the intake cam and position it so that the timing mark lines up with the head and the lobes are facing the rear. This must be done with the engine at TDC, or your timing will be off. TDC is determined with the I and not the H on the flywheel, just for reference. If you want to be sure get a piece of dowel that will fit into the spark plug hole and when it is at it's highest point then that will be TDC. Just be sure not to drop the dowel down the hole. After you get the intake cam timed, install your exhaust cam with 12 link pins between the top timing punch marks of the intake and exhaust cams. This will give you the YZ timing you desire using the stock WR cam. re-assemble in reverse order and double and tripple check the timing after the tensioner is installed rotating the engine by had slowly to make sure there is no binding. If you still need help or I was not clear enough then let me know, you can shoot me a PM or give me a call, I will PM you with my phone number and we can talk you through it. Hope this helps.

Josh

  • XRYoda

Posted April 18, 2006 - 09:18 PM

#3

I can only add one very valuable"$" piece of information. Turn the engine over by hand before you kick or crank it. In other words, make sure that the piston is not hitting the valves. I'm sure you understand.

Yoda'

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  • jbrooks26

Posted April 18, 2006 - 09:24 PM

#4

I can only add one very valuable"$" piece of information. Turn the engine over by hand before you kick or crank it. In other words, make sure that the piston is not hitting the valves. I'm sure you understand.

Yoda'



I said that Yoda, but you are correct. It is worth stating several times anyway, probably the one of the most important steps is to make sure there are not any interference problems. Thanks man.

Josh

  • Kepy

Posted April 19, 2006 - 09:25 AM

#5

I thought I did all the research - I read all the threads I could find, I got instructions from Thumperfaq.com, I printed pages from my shop manual, but I'm still stumped with the YZ timing.

Keep in mind I'm a weekend mechanic only - this is probably one of the most complicated things I've done with an engine. Laugh if you will . . .

Anyway, I got to the step of removing the timing chain tensioner - removed. then I realized the flywheels did not have the little puchmark at the top of them and the E was upside down on the right side and the I on the left. I had aligned the H symbol in the sight window and thought I was at TDC, but apparently I was at the top of the compression stroke, not the top of the exhaust stroke.

SO without reinstalling the timing chain tensioner I rotated the engine trying to get it to the top of the exhaust stroke. Did I screw up the timing or is that only if I rotate the engine after removing the cam tower? The reason I ask is that after finding TDC (as I thought) the exhaust cam has the little punchmark at the top but the intake cam has it at about 3 o'clock.
:thumbsup:

Do I have to re-time from scratch? If not, how do I get both sprockets to have the punch marks on the top? Do I just keep rotating until they line up?

I really appreciate your help. Maybe I have to find a mechanic who does house calls, but I'd rather be embarrassed in front of a computer screen than with a guy who looks at me like I'm some dumbazz which I guess I might be.


Ripmeister, cause your nick name sounds a little German I send you this tutorial from German WR site

http://www.wr400f.de...timing_cams.htm

  • Ripmeister

Posted April 19, 2006 - 10:58 AM

#6

Dank you. :thumbsup: I'm as german as Pancho Villa. But what a great site. Thanks for all the help.




 
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