Thread: BBC no oil pressure

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Help!!!!

I have 1 1978 chev 454 out of a truck. The motor has had a decent rebuild by me. Not my first motor by no means. This is whats going on. The motor was bored .30 over crank turned .10/.10 new bearnings, pistons, cam, oil pump, timing components and such. The block was clean and bored at my local macine shop. I assembeled this motor and installed in car and was priming the oil pump before start-up and was cranking with a drill for 30 seconds and had 60 psi of pressure. then the oil pressure fell to 0. I thought I was out of oil, broke pump, or bad guage. I hooked a pressure guage to the port in block and 0-5 psi while priming pump. I have no oil getting to top end of motor at all. This motor has never been cranked with the starter even. I pulled motor to check in pan. Found nothing. Pump drive is good installed new pump and pickup same trouble. pulled timing cover and checked for oil passage plugs they are installed. I have cranked pump with rear oil galley plugs out and am getting oil out the rear. Install rear plugs and have no oil coming out the front galley plugs. The motor had all bearing clearences checked upon assembly and lower end is tight. The cam and lifters are a set from comp cams and are solid lifters. The oil filter check valve was replaced also. I need help!!! Did I leave out a plug, seal, part. If you guys can help I would appreciate it Thanks Rob

Tube is tight. Bolts Tight. First pump was melling high volume with moroso pan and pickup. the second pump is a seal power high volume with a stock pick up and changed to stock pan. The primer is one I have had for years not sure who made it. I know it is turning pump as I can see shaft turn with pan off.

This may sound real dumb but you didn't per chance put your drill in reverse???

Maybe you got a air pocket in your oil pump,and now it wont ppick up.

I'm getting the same thing from my motor I thought it was just the solid lifters good thing I didnt fire it up luckily my battery was dead if you find out what the prob is or if anyone else out here can help it would be great since this was a buget build

Originally Posted by cffisher

This may sound real dumb but you didn't per chance put your drill in reverse???

that is what i was thinking if the pick up is in the pan any were in the oil it will get psi but i like them from 1/4 to 3/4 max from the bottom of the pan it will get psi is the oil pump setting flat down on the main cap with main studs the 6 side hex nut will hold the pump off the cap you said the front galley plugs are in ? did this block get hurt rod hit the oil pan rail busting to the oil feed ?the main oil feed run down the bottom side filter side of the block . i have seen them get bored in to when they bore the block to if the cut to far down in the bottom of the main web this is where they feed the mains a hole in one and you will have no oil the top get oil from the back up thru the rear cam bore were it is cut for oil if there is any junk under the # 5 cam bearing you will get no oil to the top of the engine this is where some guy will put oil restrictors in the two feeder holes they tap them for set screws with small holes drill in the under the#5 cam bearing you would never know they are in there

This is another dumbo question, just in relation to your top end not getting any oil, did you by chance mix up the main bearing shells so that the groved shels are on the caps and the solid shells with no oil holes or grooves are in the block. Any body can make a mistake if they are distracted.

Originally Posted by southerner

This is another dumbo question, just in relation to your top end not getting any oil, did you by chance mix up the main bearing shells so that the groved shels are on the caps and the solid shells with no oil holes or grooves are in the block. Any body can make a mistake if they are distracted.

that can not happen on the big block less it is 396-427 a65to67 and the rear cam must be grooved or groove the #5cam bearing would work to sorry i was thinking the cam not the mains

this is my first big block too I've checked everything thats been suggested and still no oil in the top end I knoww its building pressure cuz my drill bogs way down after about 10 secs of spinning

Originally Posted by 53 chevy pickup

this is my first big block too I've checked everything thats been suggested and still no oil in the top end I knoww its building pressure cuz my drill bogs way down after about 10 secs of spinning

you will not get any oil to the top with out the dist in the big hole that it plugs in the oil galley with out the dist in to plug it you dump it out of the dist hole one of the lifters oil galley run thru it

whew I was starting to think my motor was junk

I feel Dumb..... I found that the oil pump primer would spin in the drill chuck as soon as the pump would get some resistance. Tighten the chuck and AMAZING 70PSI. I cant believe it. Thanks everybody anywhy

hahaha..i did that 2 weeks ago..i still feel like an idiot..good luck with the startup.

good idea denny i will be borrowing that for personal use ...