[RealMcCoy]

Mitsubishi never called out to change the oil pump at regular intervals in the owners manual. I'm not sure where the 120k mile interval came from, likely the collective 3S owners as a way to help mitigate low oil pressure and spun bearings as the cars got into higher mileage.

Per the service intervals in the owners manual of my 93, they only call out mileages up to 60k which would then repeat after that.
View attachment 298371

Agreed.... I usually disassemble and check them while doing a 120K, as well as check bearing condition. I end up replacing around half the bearings I inspect, and a fair number of oil pumps, but I never just arbitrarily replace them because of mileage.

 

[RealMcCoy]

What exactly do you look for when determining if an oil pump looks good or not? I certainly don't have the eye for that and just want to keep my daily reliable for as long as possible.

Was strongly considering getting new bearings too just because of my total mileage, but my shop was saying it's unnecessary preventive maintenance because the labor involved in replacing bearings is similar to what would be done in the event of a spun bearing anyways. Honestly, not positive that bit is true as I haven't looked into the whole procedure enough, but I could see where they are coming from...

Checking for abnormal wear, gouged material, or clearance out of spec. There's inspection procedures in the FSM.

You have to have the pan off to check the oil pump, It doesn't take much time to yank the main girdle and inspect the lower main bearings. If they're showing copper, that's the best indication you need to keep looking, and likely roll new bearings in.

 

[RealMcCoy]

You can buy this one:

OEM Oil Pump Update: Sold

Selling a new Oil Pump for NA DOHC cars 93+. Part number is MD190981. $250 plus shipping gets it. Will throw in the OEM Oil Pump gaskets for an additional $15. Thanks

www.3si.org

And change the relief spring to the TT one (the only difference between NA and TT pumps for 93+), I don't have the part number handy but you can check it with ASA.

I'm not sure that's true, and it would be a good idea to confirm one way or the other... The housing on the 1G is the same, but being as the 4 bolt main block on the 2G TT is wider than the 2 bolt block, I don't know if the pump is wider as well?

In any case, the DOHC Montero pump MD302234 is the same housing and relief spring as the TT pump, but does not have the oil sending unit port in the side of it. You can always get that one and drill/tap the port into it...

 

[RealMcCoy]

The spring is MD174687

 

[RealMcCoy]

Thanks for finding me that number!

I still can't find anything conclusive on if a 93 N/A oil pump will fit onto a 93 TT. I'm starting to lean towards not. I'll update once I finally confirm.

Drilling and porting that Montero pump would be nice, but that's something I wouldn't even know where to begin. Trying to know to how smooth the port should be for oil flow and all that is way beyond me.

If the N/A doesn't line up this seems like a somewhat serious problem for vr4 owners who need an oil pump as it's gonna be tough to want to trust some random aftermarket pump...

It's just a missing hole in the side of the pump to screw the sending unit into... You would just drill the hole, and tap it to 1/8" BSPT. Not a major operation.