VirginiaF1

Congrats, glad your engine lives..
Please indulge my novice-ness:
Your original factory crank seal o-ring finally gave out
( after leaking for months)?
Leading immediately to that knocking sound?
Or did the knocking sound slowly progress to the volume in vid?
So if the O ring seal fails, the ensuing oil led to oil pump slippage,
and the poor indicated pressure?
TIA!

(once I finally hit Powerball, and can stop working,
I'm going to build a knowledge base of symptoms and repair for our wonderful cars .)

Butters944

Here's a flowchart-ish description.

The theory:

>Car leaked oil from crankshaft seal for 2+ years, causing
>O-ring failure (at some point in past two years), which
>released some tension from the crank bolt/oil pump drive
>car drove NORMALLY for x time (present<x<2years) withOUT o-ring.

THEN:

>introduction of AC to my vehicle put new stress on the crank
>crank bolt backed out a bit
>oil pump drive (another idiotic Porsche design, making it friction driven) loses grip, begins to drive the oil pump sporadically
>sporadic oil pressure from pump not running all the time leads to rod knock.

Butters944

After the AC install, the knocking sound slowly came into play as I drove the car and she indicated low oil pressure at low rpm.

It's the other way around. Keep in mind the o-ring has nothing to do with the seal; it just acts as a gripper for the oil pump drive. The leak from the crank seal led the o-ring failure, we think.

Truth is, we don't recall ever seeing the o-ring on my car, soo all of this is theory at this point.

VirginiaF1

Thanks a ton mate

Butters944

Here's my cam sprocket after the washer grinding on it from looseness...

Van

I think they did that so there would be a "mechanical fuse" in case a piece of debris got into the pump.


Wowzer!

Butters944

Haha. New one came in mail today, confirmed that the old one was indeed messed up.

Butters944

Making more progress...

So much oil it's hard to tell if it was all from the crank or not. Looks like the OPRV is leaky as well as the balance shafts. Probably gonna order more parts, might as well while I'm in there
Having trouble removing the oil pump drive...Going to remove the entire oil pump I guess. My o ring was there but it came apart in a thousand crumbly bits.

So many seals to replace

Butters944

My OPRV was missing the metal washer seal.

mclarenno9

To be clear, the primary function of the o-ring is to seal the gap between the ID of the drive gear and the crankshaft. The 165ft-lbs of torque on the crank bolt generates on the order of 10-15 thousand pounds of force sandwiching the drive gear to the end of the crank. The frictional benefit of having the o-ring compressed in there is negligible.

Butters944

So... The oil pump drive sleep was spinning on the crank, grinding up my crank.

Took hours just to get the sleeve off the crank because it had scored it up so much...

My oil pump's gasket was practically rotted away, just crumbled into tiny pieces as we pried on the pump... Is this normal??? My father plans on using gm ultra black on it.

Next step: sand/polish the crank...

"Relying on crankshaft bolt torque to drive the oil pump is the stupidest thing ever!" -my dad, senior helicopter designer at the Boeing company, with many years experience building hotrods including turbo buicks...

The damage:

Butters944

Also, my dad is afraid he may have installed my crank bolt with anti seize on it........could explain the loosening if true....

StoogeMoe

There is no gasket on the oil pump. It should be Loctite.

Butters944

Ok. Makes sense, thanks

Butters944

Updated theory.