Technical Engine won't turn!

I just rebuilt a SBC 350, everything is standard except for the stage 2 cam.
Once assembled and still on the stand. I can turn the motor with the starter (high torque) and by hand, but once I put spark plugs in it won't turn. I have checked and adjusted the journals, bearings and caps for size and torque. Everything seams fine but still nothing. I have even changed batteries, thinking that ight of been a issue.
Anyone ever see this? Any ideas.

 

do you have the correct spark plugs? not long reach, are they?

but it sounds like fun to figure it out, we don't know how much torque it takes to turn with the plugs out, so we can't really say what's wrong.

 

Does it turn freely with just one sparkplug? Two?

 

Sounds like the push rods are missing.

 

-Spark plugs are correct.
-Even with one sparkplug in it will turn until that cylinder starts compresion.
-I will have to check how much torque it takes to turn with no plugs.

 

Cam timing correct?

 

Or the timing chain.

 

Weak battery?

 

Bad Ground. Can you turn it over with a breaker bar with the plugs in? I ran into this on a car I did not build. Had Battery in trunk, ground cable to frame, No ground cable to engine from frame. would turn over with no spark plugs then quite soon as you put them in. Drove me nuts for a bit....

 

Yep cam timing good

 

Tried a new one, still same

 

Sounds like the valves are staying closed or something is hitting

Pull the valve covers and look to see if things are moving up in there

 

Pull the heads and see if still does not rotate!!!

 

cam timing is good

 

That would be something. But I'm not perfect either. Took my 2 hrs to realize I left the rotor out after a tune-up.

 

I'd go for bad electrical flow, you might have to clean a few coats of that nice shiny engine paint off from under where the ground strap goes or from under what the ground strap bolts to to make good contact. A lot of 350's have the ground strap bolt to the alternator bracket and if you painted the block and intake up real pretty and then painted up both sides of the bracket you may have a very minimal ground contact.

 

I am still trying to figure out the "adjust the journals" part.

If it turns with plugs out, still turns with one plug in until it comes up on compression stroke it sounds like you need something longer than a 3/8 ratchet, a better battery and a big bowl of spinache.

 

I told you 19 to 1 is to much compression. Check voltage at the starter when cranking

 

Quick test is when you try to crank it does one or the other of you cables or battery posts get hot real quick? That would mean a resistance in the system. That could be at the connection at the battery post, where the ends go on the cable, too small a cable to handle the load ( I don't give a rip what the self styled experts say bigger cables equal better current flow as you are moving amps not volts, the volts push the amps. ) Bad contact at the starter end of the cable or where the ground connects to the engine.

 

Are you sure the plugs aren't to long, causing the rotation to stop once the piston runs into the plug ?

 

Everything is "good", except that it isn't.

 

What the hell is a "stage 2 cam ?

 

Let's break down some before we get to three pages of SWAG's
Do you mean it's very hard to turn over under compression, using a breaker bar...or (big difference here) it stops dead with the first plug? Second? Third? and so on and so forth?

 

Tappets need adjusting maybe. The new cam might have thrown your tappet gap out so the exhaust duration is lagged not letting the chamber decompress on time. Had the problem on a Toyota once nearly blew the head off when I cranked it over. Rookie mistake.


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I could still turn over a 22:1 compression ratio engine by hand using a socket wrench. It was a diesel.

 

Yes, very hard to turn over under compression, with a breaker bar or with a high torque starter.

 

That's it then...It's got Sealed Power "racing rings" from a catalog

 

Engine is on stand, battery is hooked directly to starter and ground to engine.

 

Have you looked at the plugs to see if the pistons are hitting them?

 

upgrade from Stage 1, no where's near the Stage 3 which is also referred to as a 3/4 race.