Oil pressure..

[evilunclegrimace]

Since you already spun the engine for a while, you have circulated oil through the main oil galleys unless there is a major problem. If you fire it up and don’t have oil pressure indicated on your gauge within a matter of seconds, shut it down and find the problem. Getting oil to the top end through the lifters can take a little while longer, but that is not the same as not having oil pressure. The valve train should quiet down pretty quickly as all the lifters pump up and you get oil to the rockers. Pay attention to the sound and check for oil at the rockers after a couple minutes run time.

That is not correct.
The oil flows from the pump to the filter and from the filter to to the oil gallery that feeds the left bank lifter gallery and the distributor shaft, around the distributor shaft to the oil gallery that feeds the right lifter gallery. While it is doing that it is also flowing to the gallery that feeds the cam bearings and THEN the oil flows to the main bearings after which it falls back to the pan. The main bearings are the Last to get oil in a SBC.
Make sure that you are turning the priming tool the correct rotation and that it seals the distributor shaft bore completely other wise the oil will bleed off and fall back to the pan.

 

[thinger2]

That is not correct.
The oil flows from the pump to the filter and from the filter to to the oil gallery that feeds the left bank lifter gallery and the distributor shaft, around the distributor shaft to the oil gallery that feeds the right lifter gallery. While it is doing that it is also flowing to the gallery that feeds the cam bearings and THEN the oil flows to the main bearings after which it falls back to the pan. The main bearings are the Last to get oil in a SBC.
Make sure that you are turning the priming tool the correct rotation and that it seals the distributor shaft bore completely other wise the oil will bleed off and fall back to the pan.

I dont think hes actually using a primer.
It sounds like hes just dry cranking it off of lube.
Ill back up and look at it again but I think thats just a bad idea

 

[JWOK]

That is not correct.
The oil flows from the pump to the filter and from the filter to to the oil gallery that feeds the left bank lifter gallery and the distributor shaft, around the distributor shaft to the oil gallery that feeds the right lifter gallery. While it is doing that it is also flowing to the gallery that feeds the cam bearings and THEN the oil flows to the main bearings after which it falls back to the pan. The main bearings are the Last to get oil in a SBC.
Make sure that you are turning the priming tool the correct rotation and that it seals the distributor shaft bore completely other wise the oil will bleed off and fall back to the pan.

I think you missed the point I was trying to make. Since he spun the engine for several minutes, the oil has pumped through the lower end unless there is a problem. It doesn’t take long for a sbc to circulate oil. Agreed - that is not the best way to prime an engine, but it has already been done.

 

[evilunclegrimace]

I think you missed the point I was trying to make. Since he spun the engine for several minutes, the oil has pumped through the lower end unless there is a problem. It doesn’t take long for a sbc to circulate oil. Agreed - that is not the best way to prime an engine, but it has already been done.

I did not miss your point. What I was pointing out is that the oil did not necessarily make it to the main bearings as they are the last to get oil. Spinning the engine over does not mean that the mains are getting lubed.

 

[thinger2]

I did not miss your point. What I was pointing out is that the oil did not necessarily make it to the main bearings as they are the last to get oil. Spinning the engine over does not mean that the mains are getting lubed.

Yep, and since hes been cranking and has no oil at the top end kinda looks like a problem.
Maybe just keep crankering it.
Whats the over/ under on 2 day spun main bearings/ cam roast

 

[swervin]

Just tried turning it over with the fuel pump and all the spark plug wires hooked back up and its having trouble even turning over now? So I unplugged the spark plug wire going to the condenser and it turns over no problem.. only things I can think of is either the distributor is out 180° or maybe the crank position sensor or something?

 

[swervin]

Or is this something more major like something seized in the bottom end..?

 

[swervin]

I dont think hes actually using a primer.
It sounds like hes just dry cranking it off of lube.
Ill back up and look at it again but I think thats just a bad idea

Yea that is what I'm doing.. I don't have an old distributor to use as a priming tool

 

[swervin]

If there's no oil in the pan you're never going to see the pushrods spit oil so I really don't see what you're trying to achieve here.

Theres oil in the pan obvs..

 

[swervin]

Top

I hope youre not looking at the factory oil pressure gauge. They are worthless.
Install a cheapo mechanical gauge.
The idea behind using a priming tool on on the pump is not to build oil pressure. Its to drive the pump without the rotating parts moving against each other untill you get oil all the way to the top end so you can build oil pressure.
It can take a long time to pump oil all the way to the top.
I prime them untill i see oil then let it sit and do it again.
Remember, the oil is a "cushion" between moving parts. it keeps them from contacting each other.
As soon as your assembly lube gets pushed out, you are bone dry if nothing is being pumped into replace it.
The rub between say a crank and a main bearing if its goes dry will spike friction temperature in a seconds.
Not minutes, seconds
The rule of thumb, no oil? dont start it.
Its one thing to spin the mass with no oil and not started.
Do that with it running and no oil and the combustion stroke will smoke every bearing in it.
Im also kinda curious, when you say you did a "top end rebuild" what did you do and what caused you to do it?
Are you absolutley sure that your oil pump shaft didnt break? They have a plastic collar that the distributor fits into. Yep, you read that right. The stock ones are plastic. Throw that **** out and get s steel one.
Are you sure that the screen on your oil pump pickup isnt plugged full of sludge?
And, are you sure the damn thing didnt just fall off.
Yep, sometimes they do that too.
They are just tired
Skip some oil changes and tuneups and ignore the entire emissions systems on these and you will end up with some tar and crud that is just about good to pave a road. TBI systems will run for years after you have neglected them. They only give up when they are so plugged full of **** that nothing works anymore.
And that is when everyone gets on here after the parts howitzer has been fired
"Whats wrong with my truck"
Everything, my friend, everything
So. to answer the question about how long you can run it without oil?
About 30 seconds.

When I say top end rebuild i did everything in my garage at home, I'm deffinatly no mechanic just mechanically inclined but I planed the heads on a perfectly flat surface that I glued sheets of sand paper onto, ground the valves with lapping compound and just cleaned the hell outta them, everything was crusty, black, gaskets were baked on ect.. the reason I started that was because I found coolant in my oil when I went to drain some oil out before starting it cause I noticed it was too high. I realize I probably did alot of stuff most people wouldnt reccomend but I thought I'd try and figure it out as I went and do what I could on very low budget. So yea for all I know that plastic collar for the oil pump could be long gone, the screen on the pump could have been clogged years ago ect..