Motor will only rotate 180 degrees

I have a motor that I believe came out of a 70 Torino with stock DOVE C heads that won't do a complete rotation. I'm just starting to get it installed into the car and had occasion to attempt to rotate a full rotation for the first time, only to find it won't rotate more than 180 degrees before it comes to a dead stop. I have verified that it's not hitting the valves by backing off the rocker. The stamp on the connecting rods are part number C9AE 6210 B, are these the correct rods? A brief search on the rod part numbers seems to indicate they are for a Cobra Jet motor, are they interchangeable?

Is there a chance that a 429 piston is on one of the rods? The 429 piston has more compression height. All 385 series factory rods are the same length, 6.605".

Well, it was sold to me as a 429 so I'm assuming that's what installed. How can I identify 429 vs 469?

Here's the numbers from the side of theblock:
DOVE-A without an A on the front of the block

Front of block:
3878 with serial number OJ164833

The only sure way is by measuring the throw of the crank. There are also casting #'s on the crank that can give info on what it started out as too.

IF the motor has never been apart, and it only turns 180*..

Something ain't right inside and I think I'd be pulling it apart...

Could be rust in a cylinder not letting the piston travel all the way up. If the carb was off could be sometime got down into a cylinder with a valve open. Had a car that was transported with the intake off and they did not cover the ports or anything. Ended up with a stone in a cylinder. I'd say you will need to pull the heads and see what it going on.

Problem solved... Thanks for assisting.

The pistons are L2366 and .03 over, what would this mean in terms of compression?

What was the issue? I was about to ask you if maybe a converter bolt might be hitting something. Glad you found the problem.

Close, trans not bolted up, the bolts on the mounting plate for the flywheel were threaded into the plate and one of them was hitting the block. Doh, I hate that feeling of stupidity, especially when I probably spent about an hour trying to find the cause. Then, before I knew it I had the intake, rockers, and heads off before I had myself in a position where I could really hear where the sound was coming from when the rotation stopped.

Don't feel bad If you work on these things long enough,it will happen. Just about the time you think you got these things all figured out,they will humble you back to the idiot stage we all started in real quick. But,we learn from these little things,next time you might check that first.

Don't feel bad I had the same thing happen when I when I put a new c.a.t. flex plate on my 460 the 1st time why only 1 bolt only hit I don't under stand but it went just far enough to hit the lip on the oil pan and lock it down. Was going to say something about it until I seen where you said you found the problem.

Well the drama continues... After finding the engine hasn't been run after being told it had dynoed over 475 HP I'm beginning toe question the rest of the build. My question now is whether ther's a way to tell if the cam is stock. Are there castings that I can use to identify a stock cam?

A degree wheel and a dial indicator are the easiest way.

Blue Blood wrote:Well the drama continues... After finding the engine hasn't been run after being told it had dynoed over 475 HP I'm beginning toe question the rest of the build.  My question now is whether ther's a way to tell if the cam is stock.  Are there castings that I can use to identify a stock cam?

I know how you feel about being lied to when you buy an engine. I bought a 466 a couple of months ago, what a friggin mess  . You might follow the advice that was given you in a prior post and tear it down. If you don't, it'll always 'bug' you  

Yeah, I'm in the middle tearing it apart, that's how I was able to find find the front cam bearing was galled.  The cam doesn't appear to have suffered any damage and the main bearing look to be in good shape.  So after paying a premium for a motor that was coming off a fresh rebuild I've now purchased a new WP, front cover (hard water ate up the metal on both), timing chain (loose), and oil pump (why would I trust it?).  Add the valve covers and oil pan that paint was hiding rust, So much for a great deal...

Sorry to hear but,yea we've all been there one time or another. Chalk it up to experience and move on. 

Blue Blood wrote:Yeah, I'm in the middle tearing it apart, that's how I was able to find find the front cam bearing was galled.  The cam doesn't appear to have suffered any damage and the main bearing look to be in good shape.  So after paying a premium for a motor that was coming off a fresh rebuild I've now purchased a new WP, front cover (hard water ate up the metal on both), timing chain (loose), and oil pump (why would I trust it?).  Add the valve covers and oil pan that paint was hiding rust, So much for a great deal...

This 1000 mile since rebuilt ( by a professional builder  ) POS is into me for new rings, bearings, rebuilt heads, crankshaft turned, still trying to decide on a new cam, springs and lifters  .
Good luck  

bbf-falcon wrote:Sorry to hear but,yea we've all been there one time or another. Chalk it up to experience and move on. 

You are sure right with that statement Rick, us 'rookies' are soon to find out a deal like this is good for the experience but bad on the wallet    .

The last engine I had that acted like that had an old pocketknife down an intake port!