oil pump failure - what dies?

[nex]

just took a spare oil pump apart out of interest and they are very simple inside, so what is it that fails or is there some obvious signs of wear? does one of the rotors fracture and come apart?​

 

[jjs]

usually just wear between the rotors , or the alloy on the casing that the rotors run on wears , im sure there are tollerance details in the service manual, and there is a service kit available , but probably just as cheap to buy a new pump,

 

[red reading]

as above plus the rotor's get internal damage from debris,and the rotors and housing's also get scored too. normally it's rod bearing debris go's thru them when a big end bearing fail's

 

[Fast Guy]

rotors can fracture but I haven't heard of it on a gtir yet. (I did have one fracture on my montego when an exhaust valve collet appeared from nowhere)