engine and drivetrain #1 intake valve lash eccentric walks after 500 miles, even with the nut very tight

[RidesTigers]

Engine builders, what's the collective wisdom? Is this a 20 minute job (replace the eccentric, nut and bolt), a 3 hour job (pull rocker shaft, replace the rocker in vehicle), or an 8 hour job (have to pull the head to remove rocker shafts)? When I built this head I remember bashing out the rocker shafts was a pain in the butt on my workbench... not sure it'll be possible in the vehicle.

 

Obviously, the sure way to answer this question is to just change the eccentric first and see if it fixes the problem... but I'm trying to decide how much time to budget.

 

I read somewhere that the rocker shafts can be removed with the head in place, just have to remove the radiator. Has anybody done this recently?

 

This is an M10 with E12 head installed in a '74, if it matters.

 

Thanks!

[oldguy]

head bolts prevent removal of shafts...   impossible to do with head on motor..  have you tried loctite red?

[kbmb02]

+1 - rocker shafts won't come out with head / head bolts installed.

 

Suggestion: Change the eccentric hardware* and the eccentric itself (*use the correct hardened flat washer under the nut). If you've got Ireland's HD rockers arms, you may have/want to torque the hardware beyond the spec for factory rockers. I've never used / needed thread lock on those fasteners. -KB

[RidesTigers]

Thanks very much guys. Looks like new fasteners, locktite red and crossed fingers are my plan.

[TobyB]

Agree- also, change the lash adjuster itself.  And while you're in there, see how

snug it is in the slot.  They're supposed to be very tight.  If it's loose,

you could certainly shim it if the slot is too wide.

 

This shouldn't be a big thing to fix.

 

hth

 

t