project95gsx

I was having an issue with very low oil flow from a new Mitsubishi oil pump (whole front case). I pulled the OFH off and the middle hole on the block (supplied directly from pump) would barely pee out oil even with a full dipstick. I pulled the front case and here's the amount of water it flows (same pickup and pickup gasket, same drill on high). It's a LOT more flow than I was getting from the block. Does this look right? I'll try this same experiment with oil next just to see if the viscosity makes a difference. Idk how there could be any restrictions between the pump and the OFH outlet hole. Any guesses?
https://youtu.be/R2OrCdCFiZM
https://youtu.be/RxjFDfEAS_M

deylag

iTrader: (23)

What's the max rpm on that drill? Are you having low oil pressure when running the Evo with this new oil pump?

cficare68

iTrader: (6)

One other thing I would recommend checking is the oil pressure relief valve on the oil filter housing. Had a similar issue where i had low oil pressure as well. Come to find out the pressure relief valve was stuck open and was draining oil back into the pan instead of opening at pressures about 100 psi like it is suppose too.

project95gsx

1500rpm. I believe the pump rotates at 2x the crank so that would be a very low idle.
Yea that's how I got into this. I got the low oil psi light and my mechanical gauge was at 0. Eventually with priming the pump with a drill then putting the belt back on the oil light would go off but still had barely 20 psi. My friends evo8 is over 75psi at idle.
I tried a number of things and finally pulled the OFH off and there's barely any flow (see video). I haven't picked up oil yet to experiment with but that's my next step. Seeing how much flow (of OIL, not water) the pump moves with the same drill speed.


Yeah that's what my engine builder said. I pulled the OFH off (where the relief is located) and removed the plug, spring, and plunger. The oil behind the plunger was Black so imo it has not opened since the engine rebuild. That's when I pulled the OFH off and started checking the flow rate from the pump directly. It looked like the fluid was aerated so I was thinking there was a leak in the castle nut o-ring or in the balance stub shaft but could not feel any play and the castle but was tight with the new o-ring too. The rear housing of the pump appeared to be perfectly seated against the case. Maybe it's just from the air that what was in the pickup tube and would have eventually worked it's way out.

1) I'll do the oil test with the same drill
2) I'll pack the pump with Vaseline
3) new stub shaft (probably... I ordered a new one, the one that's on there came with the car).
4) reassemble but I'm not going to mitsu-bond the oil pan before I get good results! Ugh!

Thanks

project95gsx

Here's another video showing the drill speed vs psi output on the car. I feel like I should have made Well over 20 pounds since it made 20 pounds on very low speed.
https://youtu.be/IvE1fBB5dYE

project95gsx

Same pump. Same drill. Same pickup and balance shaft stub. Guess it's going back on!
https://youtu.be/H5go7nmNvnM

project95gsx

Primed with drill and cup and got 80psi...
https://youtu.be/VzcEHN-Jiak

Oil pan sealed up... Same issue.
https://youtu.be/vJl6pkQDEI0
Dropping the pan tomorrow and checking pickup clearance. That's all I have left.

Ayoustin

iTrader: (2)

We need more background information. Why are you doing this in the first place? Was the engine apart? If so, what parts were changed out?

Also, if you're going to put up youtube vids please hyperlink them so people who can help don't have to copy and paste the url.

deylag

iTrader: (23)

Are you measuring pressure at the oil filter housing?