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2G Does this look like too much wear on the oil pump housing?

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Kryndon

Proven Member
944
591
Jan 10, 2014
Bulgaria, Europe
EDIT: Oh wow, looks like I completely mixed up imperial and metric unit measurements when I checked it. I need to re-measure the tolerances tomorrow. Disregard what I said below.

I watched Jafro's oil pump video where he checks the clearances on his pump and found one to be junk. So I thought I should check mine before putting it on a newly built block.

Upon opening it up, I noticed that the drive gear was somewhat difficult to take out. The shaft came out with a rubber mallet. Its surface isn't perfectly smooth (I am not sure if it should be?) and on the inside of the housing some wear can be seen. Also running a 0.15mm feeler gauge, both gears look to be in spec (I think higher limit is 0.18mm and 0.16mm on drive/driven). However, both gears fail the lower limit pass, which is 0.06mm on the driven gear and 0.08mm on the drive gear. I could easily slide a 0.05mm feeler in there.

Would that be considered junk? Will oil flow quantity be severely reduced because of this? I can't afford a $300 brand new case and pump.

Here's a few pics:
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Last edited:
I get it, believe me.

I've been on these forums and playing with these cars for almost 15 yrs and I'm finally at a point in my life where I'll be able to afford a complete high power build, sad I know, but it is what it is...

I look at it this way, the oil pump is literally the heart of any motor.
You wouldn't put the heart of an 80 yr old into the body of an 18 yr old would you?

If I couldn't afford something like a $300 oem oil pump, I'd either save up, or find something to sell and buy a new oem setup and deburr the new gear's teeth.

But that's just me, if you do it right, you do it once, especially with a new build...
 
You're absolutely right I agree. However I don't think I can say if this pump is completely gone. I will do some more measurements tomorrow since I really confused the imperial units that Jafro was using in his video. I'll also look at the FSM since that usually has both imperial and metric units on tolerances and such. Also I can look at other used pumps and make sure to check them first. If I'm then out of options, I guess I'll look into getting a new one.
 
FSM shows Oil pump drive gear side clearance 0.08-0.14mm & driven 0.06-0.12mm.
 
Measured it again the right way this time and it's dead on middle of the tolerance limits. Also took some very fine grit wet sand paper both to the bore and shaft to get rid of the high spots that were causing the shaft to stick. It now goes through and turns super smoothly. Side play is also within spec as per FSM. Technically it's a 37k mile pump; that slight scoring must have happened when it spun the bearings but the car wasn't ran long afterwards, so the grooves only look bad but aren't as deep as I thought.

I know it's still a risk, but I'm willing to take it. To me, it looks like it can live on. But I'm saying it here; if I get a catastrophic failure due to the lubrication system in the future, at least I'll know what and who to blame :ohdamn:
 
So you’re reusing an oil pump from a spun bearing car? No wonder it’s all scored up.

Throw it away.

I'll see what condition the oil pump/cover is in from the block/crank I bought. Also, after looking on CAPS, it appears the 4G64 Eclipse Spyder GS (non-turbo) has the same part number for the front case and pump, just like the 4G63. Do you think you can confirm this?
 
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