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Discussion Starter #21
It bounced in your opening post when you turned on the AC.
Bouncing pressure is usually a pumping irregularity.
But, you've recorded 2 pumps doing the same thing.
The only other thing is cavitation, could you be over filling the crankcase?
After replacing the pump and getting all the parts back installed, I filled the engine with 6 quarts of oil. I’m pretty sure that it calls for 6 quarts of least that’s what I have always been filling it with.

The mechanical gauge is fluttering all of the time now no matter if the AC is on or off. The OEM pump only fluttered when the AC was on. However the OEM pump dropped oil pressure when warm. The new pump seems to do a bit better, especially when the engine is at a higher rpm.

I don’t think the mechanical gauge should be fluttering like that? I don’t have an aftermarket cam, if I did then I could see maybe the gauge fluttering that much.

other than the gauge fluttering, the engine seems to be running ok.

I did have a concern when I was installing the New timing chain. When I put the new chain on the original cam sprocket, one side of the chain was tighter than the other. Meaning the left side of the chain had more slack in it than the right side. So I bought another cam sprocket and found the same result. So I reinstalled the original cam sprocket with the new timing chain. I’m hoping this is not the issue. Replacement of the chain seemed pretty strait forward. Here’s the steps I followed:

1. Set the engine to TDC. The mark on the cam sprocket at 6 o’clock and the mark on the crank sprocket at 12 o’clock.

2. Removed the 3 bolts holding the cam sprocket to the cam. Removed the chain.

3. Soaked the new chain in oil then installed it over the cam sprocket.

4. Aligned the pin on the cam sprocket and put the chain around both sprockets. Made sure the timing marks were still at 6o’clock and 12o’clock.

5. Tightens and torqued the 3 bolts on the cam sprocket.

6. Rotated the engine by hand using the harmonic balance bolt and a ratchet to make sure no binding and the timing mark would eventually line back up.

7. Slide the new oil pump over the crank sprocket and tighten the bolts and torqued.

Once I got the cover back on, oil pan back on and all the accessory pulleys on, I primed the engine by filling it with 6 quarts of oil then holding down the gas pedal to the floor and cranking the engine 5-10 seconds at a time until I saw oil pressure at the mechanical gauge.

the only other thing I can think of is that there might be air in the Hose that leads from the port just above the oil filter that goes to the Mechanical gauge.
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