Oil pressure

[QBuff02]

My money is still going to be on the bearings are worn out, if you pulled the cap off and the bearing looked good, you'd be surprised at how worn out the top half of the rod bearings are if you spun one out to inspect it, and that's not even getting into cam bearing wear. If you did nothing else to an engine but replace the cam bearings and rods and mains just how much the oil pressure would go up with reusing the oil pump that you took out. Changing to a high volume or high pressure pump will probably raise your oil pressure on the gauge, but at the end of the day its just a crutch for the real underlying problem in the engine. Oil pressure is a correlation to bearing tolerance, and when an engine is worn out the tolerances on the bearings have opened up so in a sense you can still have good "flow" but a loose enough engine that simply doesn't build "pressure".

 

[SirRobyn0]

Ok so I'm gonna get in on this one.

It's not possible to accurately assess this engine as it is right now. He's stated that the pick up tube is missing off the oil pump. Even if the oil pump is submerged when the engine is off or at idle it's gonna suck air when you step on the gas go around a corner ect. Is there damage from it, probably. Are the bearings worn out causing the no oil pressure situation, likely. However without a pick up tube this is all speculation.

If that truck came in the shop the pick up tube AND the oil pump would get replaced. The distributor shaft would get examined to make sure it's ok and turning the pump properly. This work must be done to assess the oil pressure properly.

Then we'd fire it up, most likely find out that the oil pressure is still poor and recommend a rebuilt engine.

One thing we would NEVER even do is put a quart of 90W in the crankcase. If we really thought it needed thicker oil, we'd either put 20W50 in it, or 20W50 with a quart of hyper lube. But we'd only consider trying thicker oil, after we knew the pump could pump it ok and we'd had the valve covers off and made sure it wasn't sludge up.

 

[Buck69]

I was just thinking about your suggestion, that will be my next step, at least it's free, I refuse to just throw parts at it. Thanks for the suggestion.

Installing a pick up tube is not considered to be throwing parts at it. Pulling oil from the top of the sump instead of the bottom, will more than likely be introducing aerated oil to the galleries.
A new pump and pick up can be bought for under $100 if you are on a tight budget.

 

[Wannabe]

Installing a pick up tube is not considered to be throwing parts at it. Pulling oil from the top of the sump instead of the bottom, will more than likely be introducing aerated oil to the galleries.
A new pump and pick up can be bought for under $100 if you are on a tight budget.

I am very pleased to say that your suggestion helped tremendously. The pressure jumped right up to 30 and stayed there until it got fully warmed and then dropped to 20 and 18 in gear. This is more than enough. I'm going to flush the engine and put a new pump in and new oil. I really think after that is done it will be even better

 

[Wannabe]

Update, I thought I had this problem solved but I was wrong. I was searching Google and found a thread about the small press in cap, (freeze plug basically) that is under the rear main cap and that if it was missing the oil pressure would drop way down at idle. An internal leak. When I first started working on this I moved the oil line from behind the intake to above the oil filter, I gained 10 lbs of pressure just by doing that but it was still not right. I decideed to drop the pan, again, and pull the rear main cap. I could see something in the oil galley but it was way up in the passage near the top. I pulled the plug out of the pressure port and put a long 1/4 inch extension in there and started tapping it down, it was hardly showing any resistance at all. I heard the "plug" hit the floor so I got it out from under the truck, it was a steel ball! I had found my pressure problem at last. It was a half inch ball so it did go in the galley but had to be leaking bad and the oil pressure was holding it at the top. This is why I gained pressure when I changed ports but with it leaking like it had to have been I was still experiencing 0 pressure at hot idle. I hope my experience will help somebody else who is having pressure problems.

 

[PrairieDrifter]

There are no ball bearings in these engines. Soooooooo. Not saying this won't help someone, but there should be no ball bearings in the engine lol. I've torn down many many engines of all flavors. Chevys don't have ball bearing anything in small or big block. Definitely not a half inch ball bearing.

 

[rusted nuts]

There are no ball bearings in these engines. Soooooooo. Not saying this won't help someone, but there should be no ball bearings in the engine lol. I've torn down many many engines of all flavors. Chevys don't have ball bearing anything in small or big block. Definitely not a half inch ball bearing.

I belive there may be a ball and spring in the oil pump to reg. oil press.

 

[Wannabe]

I belive there may be a ball and spring in the oil pump to reg. oil press.

Spring yes, ball bearing no.