The car is a stock 2000 Camaro 3800 series II engine, fuel injection, ETB

Background:
The intake manifold gasket was leaking, so my step son decided to replace the gasket. In the process of re-stalling things a bold was dropped unnoticed into the valley. When the car was started the bold got down into a cylinder and busted a piston.

So we pulled the engine out of the car from the top. The heads was sent to a machine shop to be cleaned, resurfaced, two new values in the busted cylinder were replaced, and two new pushrods. A new piston was pressed on the the old rod, which checked out good. All cylinders were honed and got new stock rings. Everything went back stock.

Now the problem:
The starter will not turn over the engine with the plugs installed, all we get is a clicking. But it will turn it over just fine without the plugs installed.

We have turned it over many times with the plugs removed thinking maybe it was "tight" and needed more oil in the top of the engine and some revolutions in order to "loosen" it up some.

A new battery (12.45 volts at the starter) was installed and we replaced the starter, same problem. Took the new one back and got another new one thinking maybe the new one could have been defective. Same problem on all three starters.

We tried putting the plugs randomly into cylinders and the engine will turn just fine until it reaches one of the plugs, then the starter will not be able to turn the engine over. We then can take a wrench to the cam an advance the engine pass that spot and once again the engine rotates fine until the next plug.
When we turn the engine with the wrench, there is no drag or scrapping feeling. All the rocker arms are moving to open and close the values. All bolts were torqued to specs,

Any help would be good help, as we are lost right now on what to check or do next.

Thanks.

 

Was something changed that may have created an interference issue between the pistons and spark plugs?
Take a look at your plugs and see if any gaps got closed.
If so, the pistons are hitting the plugs and you need to figure out why.

 

Thanks for the quick reply.
I'm not sure how I'm going to check that one as the starter won't turn the engine with the plugs in. Wait I can use a cheater bar on the wrench and turn it that way. I will post the findings shortly.

 

Don't force the engine to turn over if it doesn't want to go, something is wrong!
Was this engine taken down to the bare block? Did you have the cam and timing chain off as well?
Another thought is if you have the cam swung out of time, and the valves are open wide when the piston comes to the top.
Recheck your cam to crank to TDC #1 piston references before forcing the engine to turn.
I'm not certain on what kind of clearances your engine has in a situation like that, but play it safe.

 

I assume you check plug length and signs of the plug being hit.
Remove all the plugs. Put a wrench on the forward crank bold and spin the motor over. It should move freely. Reinstall the suspect plug. It should be tight during the compression stroke only, meaning every other revolution, when it is tight it should only slow you down because the compression should bleed off. If at any point it stops and will not move forward even after waiting for the compression to bleed of you have a metal to metal contact.
Stop trying the starter until you get this figured out. A starter has more than enough torque to damage your motor. Did you check the new piston clearance? A small piston could “****” when in compression but it would have to be .030 plus too small. It seems like there is a pc of the puzzle we are missing

 

No the cam and timing chain were not removed.

 

Who was the one installing the pistons, is your battery charge up. Just wondering if all pistons look the same.

 

Thanks for all the suggestions, and I'm going to work through them one by one. Something is not right for sure, and we have missed it. So hoping your other eyes will see what we have missed.

We installed the pistons, and except for the new one that replaced the busted one all when back into the same cylinders with new rings.
The machine shop that did the heads was the one that pressed the piston on the rod. Very highly thought of and recommended in this area.

Yes the battery is charged and checked before we start trouble shooting each time.

The issue of it not cranking is not isolated to the new piston cylinder. We have installed a plug in different cylinders with the same results of the crank stopping on the cylinder that has the plug installed.

Going out to check some of the other areas suggested, and will post results later.

Thanks all

 

Starting to sound like you have a battery cable issue. Do you have a volt meter? Any idea what a voltage drop test is? If not I can explain. You should do a voltage drop test on both the positive and negitive cables. A draw test on the starter would be great but that would require some type of inductive multi meter.

How hard is it to turn by hand with no plugs? it should turn pretty easy. A started should make a completley different noise when spinning a motor without plugs in it. It spins very fast. If this is not a starter/cable issue its not looking good.

 

Did you gap the piston rings when you reassembled the engine? If they are not gapped properly it will cause too much friction on the cylinders and that will cause the engine to be hard to crank. Also with the plugs in the compression on top of the extra friction from the too tight rings may be too much for your starting system.

Massey