Indawo engezantsi yebhloko yesilinda apho i-crankshaft ifakwe khona ibizwa ngokuba yi-crankcase. I-crankcase yohlulwe yaba yicrankcase ephezulu kunye ne-crankcase esezantsi. I-crankcase ephezulu kunye nebhloko yesilinda zenziwe njengomzimba omnye. I-crankcase esezantsi isetyenziselwa ukugcina i-oyile yokuthambisa kunye nokuvala i-crankcase ephezulu, ngoko ikwabizwa ngokuba yi-oyile pan. I-oyile ye-oyile inamandla amancinci kwaye ngokubanzi isitampu kwiipleyiti zentsimbi ezibhityileyo. Ubume bayo buxhomekeke kubume be-injini ngokubanzi kunye nomthamo we-oyile. I-oil stabilizing baffle ifakwe kwi-pan yeoli ukukhusela ukuguquguquka okugqithisileyo kwinqanaba leoli xa imoto ihamba. Umzantsi we-oyile ye-oyile nawo uxhotyiswe ngeplagi yokukhupha i-oyile, ngokuqhelekileyo imagnethi esisigxina ifakwe kwiplagi yokukhupha i-oyile ukufunxa iitshiphu zetsimbi kwi-oyile yokuthambisa kunye nokunciphisa ukuguga kweenjini. I-gasket ifakwe phakathi kweendawo ezidibeneyo ze-crankcases eziphezulu kunye nezisezantsi ukukhusela ukuvuza kweoli.

I-crankcase yeyona ndawo ibalulekileyo ye-injini. Ithwala amandla athunyelwa ukusuka kwintonga yokudibanisa kwaye iyiguqule ibe yitorque ukuze iphume nge-crankshaft kwaye iqhube ezinye izincedisi kwi-injini ukuze isebenze. I-crankshaft ixhomekeke kwisenzo esidityanisiweyo samandla e-centrifugal yobunzima obujikelezayo, i-periodic gas inertial force kunye ne-reciprocating inertial force, ukwenzela ukuba i-curved bear ixhomekeke ekugobeni kunye nemithwalo ye-torsion. Ngoko ke, i-crankshaft iyadingeka ukuba ibe namandla okwaneleyo kunye nokuqina, kwaye umphezulu wejenali kufuneka ungagugi, usebenze ngokufanayo, kwaye ube nokulinganisela okulungileyo.

I-crankcase iya kuguga indawo yokudibanisa phakathi kwesiphelo esikhulu sentonga yokudibanisa kunye nejenali ngenxa ye-oyile engacocekanga kunye namandla angalinganiyo ejenali. Ukuba ioli iqulethe ukungcola okukhulu kunye nobunzima, kukho umngcipheko wokukrazula umphezulu wejenali. Ukuba ukunxiba kunzima, kunokwenzeka ukuba kuchaphazele ubude be-stroke yepiston phezulu nasezantsi, ukunciphisa ukusebenza kakuhle kokutsha, kunye nokunciphisa ngokwemvelo ukuphuma kwamandla. Ukongeza, i-crankshaft inokubangela ukutshisa kumphezulu wejenali ngenxa yokungonelanga kokuthambisa okanye i-oyile encinci kakhulu, enokuthi ichaphazele intshukumo yokubuyisela ipiston kwiimeko ezinzima. Ngoko ke, ioli yokuthambisa ye-viscosity efanelekileyo kufuneka isetyenziswe kwaye ukucoceka kweoli kufuneka kuqinisekiswe.