454 Oil Pressure Loss

[tank8970]

im looking to buy a truck with a fresh 454, not even broken in yet and im told that it has good oil pressure until it gets warm and then it looses oil pressure, he also said that when he took off the valve covers that oil barely came out of the top. just wondering what could cause this, and also if anyone would be able to tell me what it would cost me to get the problem fixed that would be great thanks

[grampadirt]

What kind of vehicle is this engine in? Was it properly primed? New crank? Did it run for a while before it had proper oil pressure?

[Airspeed-Alive]

Could be the oil viscosity? Maybe it needs thicker oil? That would be too easy though.

[2500sierra]

the viscosity thing might be a issue, since oil thins out as it gets warmer, but any significant oil pressure loss defiantly points out a mechanical problem.

[Draenor]

im looking to buy a truck with a fresh 454, not even broken in yet and im told that it has good oil pressure until it gets warm and then it looses oil pressure, he also said that when he took off the valve covers that oil barely came out of the top. just wondering what could cause this, and also if anyone would be able to tell me what it would cost me to get the problem fixed that would be great thanks

Low oil pressure is one of three things.

The oil pump is not working or is faulty.

Bearings too much clearance.

Oil passages blocked due to sludge buildup

 

Either the engine want built correctly, or it wasnt hot tanked completely.

[doverarjim]

You don't say how old the engine is. But I have seen some that where the pickup goes into the pump it will come loose a little and suck air into the pump and not have good pressure. If it is cold and has good pressure but as it warms up the pressure goes down that could be the problem. On thing you might try and I will get flamed for this is on every BB I have every ran it had one or two extra quarts of oil in the oil pan. Try that oil is cheap and see what happens. If pressure stays up then you are pumping air.

[txab]

Who rebuilt this "fresh" motor? Did they do a complete rebuild? Or maybe just half ass it? If it's having oil pressure problems now that's not a good sign. If you buy it, buy it cheap.

[2500sierra]

that oil pump pick-up is a good idea, since they are just a press in, most good engine builders will either brase them on or get a circle track style pick-up, and i would also guess that a clogged oil galley would not change with temp.