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Discussion Starter #1
The 302 in my 72 vert is tired, As far as I know it has never been rebuilt and that is something I will have to take care of...some day, but not right now.
I starts and runs fine, I've driven it every day this week.
But it has low oil pressure. With a mechanical gauge I get 15-20lbs at idle and maybe 25lbs at cruise. (10w40 for older cars)
I know the bearings are all worn but as I said I am not in a position to rebuild at this time.
However I could drop the pan and replace the oil pump. Do you think this would help enough to be worthwhile?
My thinking is that a new pump would provide sufficient oil where needed even if the bearings are worn.
Would I be better using a high volume or higher pressure pump.
I appreciate your advice...Paul
 

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You need to have resistance to have pressure. With worn bearings, the oil is just going right through the excessive clearencs from the worn bearings. You'd need a high volume pump with high pressure. Just because you have a high pressure pump doesn't mean you'll supply enough oil. Personally, I think it will be a waste of time and money changing the pump. A quick fix would be to change the bearings.
 

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Personally if you are planning a rebuild in the future, I would not tear into the motor unless you loose oil pressure completely. I would try using 20w50 motor oil and see if it helps out.

Dan
 

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Discussion Starter #4
I understand the resistance to get pressure part. (although pressure isnt really the point as long as the oil gets where it is needed. (and yes I undersand that pressure is required to move the oil to where it's needed)).
I don't understand how changing the bearings would be a "quick fix". At a minimum I'd have to disconnect all the rods and drop the crank (I guess this could be done without removing the pistons from the cylinders) I could then replace the bearings and put it all back (Although this hardly seems like a quick fix even if I did it all with the engine in the car). But how much difference would this make if the crank is not ground?
At this point I might as well bore it and replace the pistons are rings (plus cam and cam bearings). Not something I am in a position to do right now.
Am I missing an easier way to do this? (I might just try the 20w50)
Thanks...Paul
 

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You can replace the crank bearings with the crank in the car. You would have to roll the old ones out and roll the new ones in. You can also replace the rod bearings with the crank in the car as well. I would probably remove the engine and put in a crank kit. You don't have to remove the pistons..unbolt the rod caps and push the pistons into the cylinders. I don't think there is a "quick fix", but this would be cheaper than total rebuild.
 

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I used a high volume melling oil pump on my old engine. It did help. First I would try thicker oil. I did this to get me by till I could afford a new engine.
 

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I don't think there is a "quick fix", but this would be cheaper than total rebuild.
Exactly, this is what I meant by a "quick fix", not that it could be done in an hour but the total amount of money & time to changing bearings, vs rebuilding would most likely get it running with acceptable oil pressure for a short term untill you could properly rebuild it. It would be a down & dirty repair.

Stock oil pump drive shafts aren't exactly known for holding up against high volume/pressure pumps, especially if you start running heavier viscosity oil. If the shaft fails, this could cause more problem then you'd want.
 

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I quickly read throught the posts and thought Kiwi was askingif there was a quick fix...sorry.
 

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I quickly read throught the posts and thought Kiwi was askingif there was a quick fix...sorry.
 

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I second the thicker oil, until you can pull the motor and rebuild it. I run 20w-50 in my 351w. In my old 302, the motor smoked, and leaked everywhere, and I had a problem with oil pressure, so I ran straight 50 in it to keep the pressure up. My friends used to laugh at me because I drove everywhere with a case of oil in my back seat. It was my everyday driver, and she leaked/burned 1 1/2 - 2 quarts a week. I say if you're going to go through the work of replacing bearing, and an oil pump, pull the motor. If it's your driver, and you want to keep the original motor, swap in a junkyard motor, and drive your car while you rebuild the original. You could also buy a ready made short/long block assembly. There are a lot of options.
 

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Can the car be "down" for a few days/week?

How much money CAN you throw at this problem right now?

I second replacing the crank bearings. Ideally, you'd have the crank reground on the main as well, but that would most likely be a waste of money since you're going to have to do it again in the future.

The logic behind replacing the bearings is that the babbit(sp?) material in the bearing is softer than the iron crank. thus, while the crank wore a bit, it didn't wear as much as the bearings. By replacing the bearings, you reduce your clearances back to something "closer" to stock, but not quite (you would use original size bearings however). By gaining some clearance back, the oil won't flow as easy, the pressure will come back up, and hopefully, get further down the oil galleys.

This is by all means a stop-gap approach, but it sounds like the right answer for the question you asked. I'd think that this would cost in the neighborhood of $100, maybe a bit more. You'd need the bearings, and oil pan and timing cover gasket kits (plus tools incl. torque wrench and balancer puller). That's about it. You could do the pump at the same time, however, as the others have said, you'll want a beefier pump driveshaft for the high pressure pump. Personally, I think the money is better spent on a new timing chain before a new pump in this case.

The junkard motor is another stop-gap approach, but I would guess, would cost more.
 

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Before anything else, try Mobil 1 15W-50.
 

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Discussion Starter #13
Thanks for the suggestions. I'll try the thicker oil. In fact I'll try the synthetic as suggested (and hope it doesnt promote leaks).
...Paul
 
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