M113 engine rebuild - Part 5 - Cylinder head rebuild. lapping valves and vacuum testing heads.

[@sonyhk3824]

Nice well done man 👍

[@all_balls_drift]

Thanks for the vids! Could you reference where did you get 0.8 - 1.2mm contact line width from? Cannot find this info anywhere

[@JMSpeedshop]

This in the Mercedes manual

[@tylerhayles]

Do the valve stems wear themselves?
Do you know of there is any clearance specs for them? Im changing my valve stem seals but thinking if the stems themselves have worn down abit oil will seep past

[@JMSpeedshop]

There is a dimension for the valve and a clearance for the valve guide. If this is touch the valve will move to much this can also cause the seal to let so oil trough but a valve stem. Wear out by the seal. I have not seen

[@bigsmk9168]

When assembled close the valve until sealed. pour some shop cleaner behind the seated valve and If it does not leak or seep through you’re good to go.