Plug in cylinger head

[jpane]

I tried to attach a photo of the area in question, but could not. Probably need some coaching. Just behind where the high balance tube manifold for the Z-S carbs attaches to the head casting, there is a hole. (I forgot to check whether it is threaded.) My mechanic thought it might be a freeze plug. Does anyone know the dimensions and type of plug?
Thank you, John

[BDA]

Here is the "official" method of resizing your photos: http://www.lotuseuropa.org/LotusForum/index.php?topic=1379.0
Some people, including myself, have found this method helpful: https://www.youtube.com/watch?v=O_55eg00H-w This is Windows centric but Macs have a similar tool that works similarly.

Without a picture, I'm guessing it is the crankcase breatherthat goes from the head to the carb airbox. It is behind the carbs and the hole in the head is appox. 1/2" or a bit more. In the attached picture, part #9 is the breather tube I'm speaking about. There should be a rubber grommet that seals the tube to the head (it just pushes in). If you don't have this part any more, r.d. enterprises has them for $122! SJ Sportscars has them for ~$46. You could probably make up something for even less.

If I'm incorrect, maybe you'll be able to post a picture of what you're talking about.

[jpane]

I think you are right, that jogs my (failing) memory. anI believe I had a piece of tubing bent at a right angle down out of that hole, and just exiting to the atmosphere, since I no longer have the airbox, but just individual circular air cleaners on each carb.
Thanks very much, John

[BDA]

You can vent your breather to a catch can or to a filtered breather (lots of pretty ones on ebay).