454 bb low oil pressure

[man-of-war]

hellow all , i had this engine rebuilt twise. the first time when i bought the boat last year the oil line broke ,ran with out oil for 20min to get to land.the michanic said he's going to change all the bearings in the bottom half of the enging .took the boat out today,the oil reading is 40 psi at idle cold,and runing temperature hot is 25psi at idle. as i give more gas the psi goes up and stays at around 50 to 55 psi .i need a leg to stand on when i take the engine back on monday . any ideas or sulitons will be noted .

 

[Don S]

Re: 454 bb low oil pressure

Sounds about right to me, book for a 93 to 97 Mercruiser says 30 to 70 psi at 2000 rpm and 4 psi min. at idle.<br />Since you don't mention what you have, other than a 454, that's the best I can do.

 

[Bondo]

Re: 454 bb low oil pressure

Ayuh,.............<br /><br />That Sounds like a Typical Chevy V8...........

 

[Trent]

Re: 454 bb low oil pressure

Like was said....normal

 

[man-of-war]

Re: 454 bb low oil pressure

sorry for the lack of info, the engine is a 1979 bb 454 with an ebelbrock proformer intake which was ported to match the ports on the head.the cam was also changed with an extream marine comp cam 1000 to 5000 RPM , aluminum roller rockers 1.7 ratio, thunderbolt V,and a blaster 2 coil.through hull exhaust. the timing was set at 16 degrees. i hope this would fine tune the problem. THANKS

 

[man-of-war]

Re: 454 bb low oil pressure

more info, after the engine was rebuilt the first time i was geting 80 psi hot or cold, idling or runing. also after first rebuild i was geting 55mph plus at 4000rpm now the mph is matching the rpm .3000rpm 30 mph . THANKS, KNOWLEDGE IS POWER

 

[Don S]

Re: 454 bb low oil pressure

the first time i was geting 80 psi hot or cold, idling or runing.

That, right to start with indicated something was wrong, what you now have is more inline with what the oil pressure should be.<br /><br />Why are you wanting to take it back to them? Will it not run up to WOT?

 

[Don S]

Re: 454 bb low oil pressure

i was geting 55mph plus at 4000rpm now the mph is matching the rpm .3000rpm 30 mph

Can you now get 4000 or even better around 4600 to 4800 rpm out of it now?<br />If you can still get the same rpm's as the previous rebuild, and only the speed dropped, that has nothing to do with the engine. The engine is still giving you the rpm, it's the boat that lost the speed somewhere. Did you change props?

 

[man-of-war]

Re: 454 bb low oil pressure

I was told by the mechanic to run the engine 6 to 10 hours at 3000 to 3500 rpm to break in the cam. I did 6 hours this weekend. He said the oil must be changed for the final tuning. The last 10 min I did punch the throttle a bit to 4500rpm just for a second, but it could have met that 5000 rpm with ease. I noticed today alot of disturbance in the water, as if the hydrolic lines for the leg were being dragged but only on the right side and no, I never changed the prop. Don S - I do want to thank you for the information about the oil psi and rpm thing THANKS