Got the new motor all hooked up. and I can't get any oil pressure. I tried pre-lubing by cranking it over with the starter w/ coil disconnected and fuel injector fuses pulled with 10 second cranking increments and I havent got anything. I connected it back up and started it and let it run for about 13 seconds and still didnt get any.
It has a new sensor so it's not that
What do I do?

 

This might sound dumb. But are you sure the drive is on the back of the cam and the oil pump shaft is correctly on the drive and the pump? The screen might also be set to low or high (if it isnt set right you may have no Oil pressure showing) Just a few things to look at. You might want to go out and buy and autometer gauge and hook it up and see if you gauge in the cluster is bad.

Matt

 

It's got oil in it? Are you sure the pickup is installed? Are you sure the connector is plugged in and that it's the correct one? Maybe the sender is bad? No offense intended, just starting with the basics...it's easy to overlook when you're involved in a big project sometimes.

 

I don't know if the oil pump was hooked up correctly. My builder at the machine shop did it all. It has oil, pickup is installed and welded, connector is plugged in and correct. I dont know if the screen is in the correct place. I do know that he had to modify the windage tray to clear the crank though.

 

Are u sure that the dirve gear was dropped into the hole in the back of the lifter valley. Because the lt1's dont use the typical distributor there has to be a gear dropped in the back in that hole, thats where the drive shaft is. If it is there then u would see a little arm hanging off the top thats bolted to the block. I forgot to do that once and I had zero pressure of course.

 

When I did my rebuild I primed the same way as you but it took a good 45sec before I got oil pressure. Sounds simple enough maybe you didn't crank it long enough, or not. I remember when I was cranking it thinking wow this is taking long and then bam oil pressure.

 

If you ran it for 13 seconds without oil presssure that's enough to do damage. I would not be starting it until you are sure you have oil pressure.

 

Mine had oil pressure after 2-3 secs....
Im betting the oil pump shaft isnt aligned correctly or they forgot to install it...

Cody

 

You may have broken the sender when you reinstalled the engine. Being plastic, it isn't hard to do.

 

I don't like the cranking with no spark/fuel to get the engine primed.

I know thats how the shop manual says to do it but it still seems a bit goofy to me.

Get a 90 degree drill and a old chevy distributor. Remove the oil pump drive gear and prime the motor, just like you would any other SBC.

In a few seconds you have oil going everwhere without dry turning the shortblock.

 

yeah, Id say def. take off the intake and remove the oil drive shaft. make sure there is an oil drive shaft down in the block at the end of the oil pump drive gear. i prelubed mine with the sbc priming tool and a air drill it took about 45 sec. to get oil comeing out the pushrods bleeding onto the rockers. I kept goin till all the rockers had oil comeing out on them. that took about 2 min.s it seemed like. the long time may have been caused by the packing of grease I put in the oil pump to make sure the pump will pull fluid into it. an easy way to tell if the gauge isnt working would be to pull a valve cover and see if the rockers are getting oil from the pushrods.

 

i friend of mine has a similar problem. Turned out, they forgot to put one of the freeze plugs on the front of the motor, inside the timing chain. Caused it to have zero oil pressure..

 

oh yeah, something else they could have forgotten is the ball plug that goes in the block in the back main cap galley. just keep your fingers crossed its something simple.

 

Before you get crazy with tearing the motor apart you might want to pull the oil filter and make sure the reliefe spring and disk is still in the by pass adapter. That may also give you a clue if the oild pump is moving oil and the guage is wrong. I see a lot of rebuild shops reuse those by pass adapters. Cheap Cheap instuance if you are deoing your own motor. The springs often times get really trashed if the machine shop runs it through the hot tank when they do the block.

 

I would put in a manual gauge, and see what you find out. Also i had a spare oil sending unit out of a caprice and put it in my motor when i first started it and it didn't read either. I replaced it with my old one and all was fine. I guess what i'm getting at is if you have the wrong sending unit that might be the problemt to.