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Oil pump issue


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So I resealed the front of the motor because the leaks go so bad. She was smoking like a chimney after getting off the highway!

After resealing I seem to have less idle oil pressure, but after reving it's fine. On the gauge it's like barely over idle hot. It use to be 1/4 way up the gauge. If I rev it to 1k it jumps up the 1/4. By 1500 I have 50+.

 

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Odd...   Idle oil reading hot is always very low.  On all of the several EA82 cars I have owned.  It's only around 5psi.  You have to connect a mechanical gauge if you really want to know what's going on.   When you did the reseal, did you remove the oil pump?   The only seals that could cause a change in oil pressure are the o rings and shaft seal on the oil pump.

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18 hours ago, GeneralDisorder said:

The "trim package" on the dash is not an accurate "instrument". Check it with a shop gauge. 

GD

Mine is less than a pound off. I used to have a electronic sender guage as well, but the dash guage was always accurate, so I removed it.

23 hours ago, DaveT said:

Odd...   Idle oil reading hot is always very low.  On all of the several EA82 cars I have owned.  It's only around 5psi.  You have to connect a mechanical gauge if you really want to know what's going on.   When you did the reseal, did you remove the oil pump?   The only seals that could cause a change in oil pressure are the o rings and shaft seal on the oil pump.

I replaced both seals. I don't think either could leak without leaking externally, which I thankfully don't have anymore. Odd think is the oil pump seal I removed was pinched, and was the source of my growing oil leak. 

 

Maybe I f'd up and put the oil pump ring in backwards? Though I'm like 90% sure I had both letters up.

Edited by Turbone
Family friendly guys, remember?
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Still - things have changed so you should check it with a shop gauge. Could be an issue with the sending unit. 

And the FSM and Owners Manual both state that seemingly zero pressure at idle on the "trim package" is "normal" and expected operation. 

The General Rule for oil pressure is 10 psi per 1000 RPM. Of course we generally like to see it higher than that, but that's the generally accepted number for operation without damage. 

GD

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13 hours ago, Ionstorm66 said:

 

I replaced both seals.

Aren’t there 3 on EA82s?  
Shaft seal, Mickey Mouse gasket and an oring?

XT6 only have the shaft seal and Mickey Mouse gasket but people accustomed to EAs used to toss the oring on the XT6 too because the pumps look the same. 

Edited by idosubaru
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14 hours ago, idosubaru said:

Aren’t there 3 on EA82s?  
Shaft seal, Mickey Mouse gasket and an oring?

XT6 only have the shaft seal and Mickey Mouse gasket but people accustomed to EAs used to toss the oring on the XT6 too because the pumps look the same. 

Where is the o-ring? I did the crank, cams and oil pump shaft seals, plus the mickey mouse. I didn't take any orings out of the oil pump, but that could be my issue. 

 

Also replaced the water pump because it was leaking. Turns out it was leaking from the gasket, not the shaft. There was a big glob of antiseze in on the gasket surface. Guess I have a spare water pump now, just need a spare gasket.

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If it's not leaking then yes, that's a good thing.  

[update below]

Did you change the oil filter when you resealed the pump ? 

If so, then the old oil filter may have been extra dirty and giving you a higher pressure reading.  The new filter is clean and could be resulting in a lower pressure reading.

Edited by Dee2
update
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13 hours ago, Ionstorm66 said:

It isn't leaking out on the ground, so I doubt that is bad right?

What does a leak have to do with this?  If you’re concerned about leaks that’s a separate topic. the point is:

1. You’re missing an oring

2. You’re concerned about oil pressure

Lack of leakage seems immaterial to those two points.

Not all orings prevent external leakage - some seal components internally

Those gauges read notoriously low - some of the owners manuals indicate this. I realize you tested it at one point - that doesn’t mean the sender or gauge are as accurate now as they were.  Maybe they are.

Maybe they aren’t. But it’s not far fetched to expect a 30 year old engine to not be factory new, particularly with known issues.

I don’t know what that missing oring does. my guess has always been: very little.  but you suspect issues after working on the oil pump and it’s missing an oring. Seems logical to find out what that orings does, Ask about it and/or replace it while verifying the other components. 

The FSM also specs sealant at the 12 o’clock and 6 o’clock areas where the oil pump rests against the block halves junction. 

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On 2/6/2021 at 12:59 AM, idosubaru said:

What does a leak have to do with this?  If you’re concerned about leaks that’s a separate topic. the point is:

1. You’re missing an oring

2. You’re concerned about oil pressure

Lack of leakage seems immaterial to those two points.

Not all orings prevent external leakage - some seal components internally

Those gauges read notoriously low - some of the owners manuals indicate this. I realize you tested it at one point - that doesn’t mean the sender or gauge are as accurate now as they were.  Maybe they are.

Maybe they aren’t. But it’s not far fetched to expect a 30 year old engine to not be factory new, particularly with known issues.

I don’t know what that missing oring does. my guess has always been: very little.  but you suspect issues after working on the oil pump and it’s missing an oring. Seems logical to find out what that orings does, Ask about it and/or replace it while verifying the other components. 

The FSM also specs sealant at the 12 o’clock and 6 o’clock areas where the oil pump rests against the block halves junction. 

If the o-ring I missed in the oil pump leaked, it would then be sealed by the larger part of mickey mouse seal. They both seal the same area. Unless the seal has only failed in the tiny area between the small passages and the main pump area, there is no way for the o-ring to leak pressure without an external leak.

Also I'm not missing the o-ring, I just failed to replace it. The oil seals had been replaced before, and the mickey mouse seal was install improperly then causing the leak. It was pinched on one of the small passages.

Also the gauge is still on the money as the cold pressure is still at the same spot. It just drops like a rock when warn. Maybe I got bad oil and it's just thin?

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On 2/7/2021 at 9:21 PM, Ionstorm66 said:

The oil seals had been replaced before, and the mickey mouse seal was install improperly then causing the leak. It was pinched on one of the small passages.

 

That’s actually really common and usually not an improper installation. I have no idea how many of those I’ve seen with the same pinched smaller circular passage of that gasket.  I’ve probably got some old ones laying in my garage and we could google images of the same.

Im unsure what causes it but Ive suspected inconsistent mating surface clamping force between the pump body and engine block which allows that portion of the gasket to get sucked in. 

keep driving it and the new gasket has a good chance of doing the same thing.

If you don’t have any ticking then this is probably a nonissue.  Besides ticking the pumps are robust.  high mileage or warn engines will have internal wear influencing oil supply which won’t be remedied at the pump.

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  • 2 weeks later...

So I'm now 90% sure it was bad oil. Used the same brand and weight today on my change. Now am back up to 30 psi idle 50 cruising, and 60 peak.

I'm going to send the oil off to get tested and see what they say. Didn't see any flakes on the oil and never heard anything bad. Also didn't have any super hot weather so that helped.

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