Can anyone ID this valve train plug? Critical? Keeps backing out

[SP3]

In performing multiple valve adjustments recently (2 occasions- 1 cold and other warm) I noticed this threaded plug keeps backing out. Original thought was it was something to manually add lubricant to that part of assy upon rebuild??

At any rate it keeps backing out and that can’t be good.

I tried adding some layers of Teflon thread tape to take up play and force tighter thread engagement.

Is applying Red Locktite a recommenced fix?

[Linda]

That goes into the hole and should thread all the way down .It helps with oiling.The valve train shaft has to to be turned so it threads all the way down.
Linda

[theunz]

I would not use red loctite, but would use blue instead. I’m not familiar with the 1600 and don’t know what that plug is for, but if you need to remove it after using red you will need to use a torch to heat it up first.

[Linda]

A few links on this, it is called a rocker shaft set screw:
viewtopic.php?f=2&t=31208

viewtopic.php?f=2&t=10710

Linda

[JT68]

That’s not a plug, As Linda says it is a set screw. It retains the ticker shaft preventing it from rotating and migrating (blocking the oil hole) It is fairly important. Red locktite would be fine if you can get everything clean enough.

[SP3]

Thanks for the responses.

I think I will try the Loctite option cleaning first with the carb cleaner and catching residual with a cloth.

Makes one wonder what other similar parts/assemblies are inside our drive trains hidden from view that if come undone could ruin a great day out on the road - the comedy and tragedy of vintage motoring...