I'm getting ready to have to replace one of my rocker arms & the rocker shaft that fits inside. It's for the no.6 intake valve. It seems to have some uneven wear in the shaft & has caused it to have a lot of side to side play in it. enough play that valve lash is not the same when the rocker arm is moved from side to side. It's also causing a ticking noise from the play in it.

I am just wanting to make sure about something. Should I have the engine turned to Bottom Dead Center before replacing this rocker arm or does this matter. My gut feeling is that it is supposed to be on BDC because that is where it needs to be to check the valve lash on intake no.6 but I just want to make sure so I don't cause any problems. I'm not planning taking out push rods or changing anything else...just rocker arm....

Thanks for any help or suggestions.

 

nobody has ever had to replace a rocker arms on their truck?

 

Roll the engine over until both rockers are loose on #6, just as would be adjusting the valves on that cylinder. Then change the rocker out.

 

thanks. that's what i was thinking was right, but I wanted to make sure. i remember reading somewhere not to ever remove them when on certain valves when the engine was on TDC?

 

If you were changing a rocker on a different cylinder, you'd do the same thing. You would want that particular cylinder on TDC or somewhere near TDC, the valves would be closed.

 

It doesn't need to be closed to change it, but you will need it there to lash it, so it makes sense to make sure its closed first.

How do you know that the rocker shaft is causing the side to side play? The shaft is a constant diameter, sans the milled area for the bolt head. Its the fulcrum seat that would limit the side to side play.