Cam rotated after lock nut removal

[MAS956]

Hi Guys,

I'm helpinng a friend address the head stud issue on his '79 SC. Working on the cam sprockets with the engine at TDC1, I noticed after removal of the cam lock nut that the DS cam was rotated about 30 degrees clockwise. All valvetrain components are still installed.

Is this normal? I'd hate to bend any valves!


Thanks,

[sammyg2]

If the cam has spring pressure on a lobe it will turn when the nut is loosened.
A good practice is to back off all of the valve adjusting "elephant's feet" prior to loosening the cam nut just in case.

Hopefully your valves did not hit the piston and if they did, there wasn't enough force to do any damage.

Before going any further I recommend backing off all the adjusters, just don't go too far or you will force the elephant feet off the adjusting screw.

[sammyg2]

Just another thinking out loud type of thought, I would guess that it would be awfull hard to pull the alignment pin if there was significant spring load on the cam, so if the pin came out easy maybe it didn't have enough force on it to bend a valve?

[john walker's workshop]

usually they stay put if the pin is pulled at TDC #1. it must have been rotated. no big deal, just turn it back so the keyway is at the top. you're going to redo the timing anyway.

[MichiganMat]

you're fine.

Now, just make sure you know the measurement scale of your dial indicator (inches, centimeters, etc) and you'll be on the road to success.

[MAS956]

Thanks John,

This is my first time dealing with the cams and just want to make sure to not screw something up.