My dad bought a Waltons Celestial 160 new and I can vaguely recall the unboxing which would have been between 1977 & 1978 (I believe mowers often remained in stock many months after manufacture.)
I remember V177 on it's throttle assembly. He took it for a major service in the early 1980s and that's when it must have gotten it's white primer cap. I see a service bulletin from 1978 instructing Victa dealers to fit them whenever a mower was brought in for services. I retrofitted one to my nan's Pace Premier 160 in the 1990s. It made starting way easier.
Just checked the KMart 125cc store brand I found last year, and it still has V170 on it's throttle assembly.
Ahh, if only victa had kept producing the thumblatch catcher series, they would be in better shape today!
| 
