Pictures would help.
People are lazy and dont like to search, but will help.





Clean it out and try it.


Or buy a new one US$40
http://www.mowers4u.com/oregon-tecumseh-carburetor-hm80-hm90-hm100-p-787.html

Heres an overhaul kit US$10.95
http://www.mfgsupply.com/m/c/22-10948.html

Bruce may be able to get you either of the above in the store if you message and ask.

Some of the mower engines have a fixed size jet others have and adjustable jet. I assume this will have one or the other. If its adjustable it might need tuning.

[Linked Image from mowers4u.com]

Theres three different carbs apparently.
[Linked Image]