I have an old Tech engine snowblower and it starts great and everything , but recently it has started acting-up it lacks power and dies when warmed-up please help:confused:

Try tightening the mixture screw by about 1/4 turn clockwise. See if it runs better and will stay running for about 5 minutes before you refine your mixture. If you can get a tachometer I think you will get a better running engine than adjusting by ear. If the 1/8 turn makes thinga worse the go 1/8 counterclockwise.

Definitely use a tach.