Hi Paul and members
A nice one for the record. Many thanks smile

I suspect the old-style 'ticklers' on carbies merely were vacuum
release devices - so that tank head pressure could do its job.
The prime objective was to fill the carby bowl, not ensure a
fuel charge for quicker starting.

That was left to good carby design and general condition
of the engine that does the 'sucking' of the fuel.

That's my amateur understanding, anyway blush

Some carbies prime better than others,
and I have heard comments that support what you say about that carby.

It is interesting that in 1964 Victa re-produced comments about this:-
https://www.outdoorking-forum.com.au/forum/u...a-news-cuttings-june-1964.html#Post95680

I think modern primer bulbs do a better job - they do prime
rather than fill a fuel bowl.

Cheers
-------------------
Jack