1G 1g oil case 2g gears?

[AlmightySo]

I just opened up my oil pump to inspect for any signs of marks inbended. I then noticed it has the worm gears thats in the 7bolt case. I know this is a 1g oil case due to the bottom of it being completely flat.
Is this fine? It does have a few marks and i can feel em with my nail, i can upload pics if needed

 

[spyderdrifter]

Well, 1Gs did have the 7 bolt starting in '92, what year is your engine? If you don't know for sure, the VIN should be stamped around the water neck area if it's not the original engine.

 

[donniekak]

Only the 1990's have straight cut gears.

 

[19Eclipse90]

The "worm" gears, or helical gears, were in all late-model 4G63-powered DSMs -- all 7-bolts for sure. Generally, the "straight-cut", or spur, gears are attributed to the 1990 models. Mitsubishi ASA shows them being used in some 1991 models as well but not in 1992 models.

Oil pump gear swaps

 

[steve]

Yes they were in '91's. There was a TSB to replace them with the helical gears if the customer complained about noise.

 

[AlmightySo]

Thank you guys for the info, soon ill become a walking book
From my research helical gears have more of a thrust load and causes a quicker oil pump failure. Id like to post some pics of my case and see what you guys think, re-use it and buy straight cut gears, & drop em in or buy a whole new case. The stub shaft area has spots i feel with my nail.
My engine is currently at the machine shop, should be picking it up this week and ill know what year it is for sure.