Knocking noise after fresh oil change...

[joe_peters]

As indicated in the article I linked to on page one of this thread, your oil pump may be loosing its prime.

Try this on the next regular oil change: refill the oil as quickly as possible after draining.

 

[winterbeater]

Maybe dirty oil is better. I hope so, because mine is. :laugh2:


Me 50k miles later: :tears:

 

[dunbad]

Yeah maybe start pouring as we start draining!)))

 

[orange]

Sure hope those are good readings, mine are the same!!

What I was referring to is a cold start after several hours off, the pressure has a short time delay building up from zero.

From when you engage starter to say a 30lbs+ reading there is about 2-3 second delay. If its like 10-15 seconds or more, there is a bad 'anti-drainback valve' in the filter or something wrong with system which allows the oil system oil to drain back into the oil pan.

The oil pump has to refill the filter and oil system from 'Empty' each time if no anti-drainback. With anti-drainback it holds the filter/oil system 'Full' for next startup.

Regards,
Orange

 

[winterbeater]

Yeah maybe start pouring as we start draining!)))

Maybe change only half the oil at once!:jester:

 

[CommanderXJ]

Sure hope those are good readings, mine are the same!!

What I was referring to is a cold start after several hours off, the pressure has a short time delay building up from zero.

From when you engage starter to say a 30lbs+ reading there is about 2-3 second delay. If its like 10-15 seconds or more, there is a bad 'anti-drainback valve' in the filter or something wrong with system which allows the oil system oil to drain back into the oil pan.

The oil pump has to refill the filter and oil system from 'Empty' each time if no anti-drainback. With anti-drainback it holds the filter/oil system 'Full' for next startup.

Regards,
Orange

When I start the car when it's cold it jumps to 80 psi at idle while it warms up. As I drive it for 30 minutes, the psi starts to drop to about 40. Realistically, it shouldn't take the car 30 minutes to fully warm up. I live in AZ so the car probably needs maybe 5 minutes to get to operating temperature.

I am thinking my sending unit is either busted or something else. But again, the filter I have on there now has got a good anti drain back valve.

 

[orange]

Yes it do take 20-30 minutes to warm up. (Same for AW-4 transmission!)

The coolant is mostly in the top of the engine so 3-5 minutes warm, but there is a LOT of metal in the bottom part which takes quite a while to warm up fully.

I agree the readings seem a little high but believe that is the error in the oil pressure sensor, HOWEVER! If engine is making any strange noises then verify with a mechanical gauge soonest, at Startup, cold, and hot readings. Spec is minimum 13 lbs at hot idle.

As the oil / engine heats up the oil thins and clearances change so ~20 lb drop cold to hot is usually normal.

 

[joe_peters]

Yes it do take 20-30 minutes to warm up. (Same for AW-4 transmission!)

The coolant is mostly in the top of the engine so 3-5 minutes warm, but there is a LOT of metal in the bottom part which takes quite a while to warm up fully.

Exactly!