Craftsman/Tecumseh engine year help

[manchester1]

I have a Craftsman H25 engine. How do I tell the year?
143-641042 Serial number 40980 Not the round top on the shroud but I have had this engine/edger for a long time. It was my grand fathers.

 

[old shed finds]

1980.
Marcus? In 80% sure in right.

 

[capguncowboy]

it's either 74 or 84. Got a pic?

 

[markus]

1974, they ended the H25's in 1975

 

[Davis]

1980.
Marcus? In 80% sure in right.

You was close.

 

[manchester1]

1974, they ended the H25's in 1975

Thank you @markus . I knew it was pretty old.

 

[manchester1]