grease monkey
US /ˈɡriːs ˌmʌŋ.ki/
UK /ˈɡriːs ˌmʌŋ.ki/

1.
mecánico, grasiento
a mechanic, especially one who works with cars or other vehicles and often gets dirty
:
•
My brother is a real grease monkey; he loves working on old cars.
Mi hermano es un verdadero mecánico; le encanta trabajar en coches viejos.
•
The old grease monkey at the garage can fix anything.
El viejo mecánico del garaje puede arreglar cualquier cosa.