Valve Lash JD 790 TDC??

   / Valve Lash JD 790 TDC?? #1  

Flywheel

Bronze Member
Joined
Jul 27, 2006
Messages
79
Location
Elgin, TX
Tractor
790
I have on '05 JD790 with a 3TNV engine.

I was adjusting the valves using the operator's manual and it appears that either the manual is wrong or my flywheel is wrong....

Anyway, the manual says to turn the flywheel until the cylinder 1 mark lines up with the housing mark - and then do the same for cylinders 2 and 3.

My flywheel has 3 marks about 1/2" apart, then another mark with a 3.

On the opposite side, or so, it has 3 marks, and then another mark with a 14 (I assume the timing mark....

Anyway, does anybody know the official way to adjust the valves on the 3TNV?



Thanks in advance....
 
   / Valve Lash JD 790 TDC?? #2  
Who cares where the flywheel is? All that is important is to set the cam lobe position to where there is no lift. That's usually 1/2 turn of the cam away from where there is full lift. If the crank to cam gear ratio is you-know-what, then we can get on to another issue, such as whether or not reuse the old valve cover synthetic rubber gasket or order a new one from the dealer 12,000 miles away for $329 plus tax (and $480 next day shipping).
 
   / Valve Lash JD 790 TDC??
  • Thread Starter
#3  
Exactly - thevflywheel marks should tell me where tdc compression is - I guess I'll just get the cylinder rocking and then rotate full turn for each cylinder. I think once I get #3 done - then I just move 240 degreesnand do # 2, etc.

Thanks.
 

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