New Rebuilt Engine - Pistons not moving
 

Hello
I have a rebuilt engine for 1930 Model A and finally finished install last week. Today went to crank the engine by hand to set the timing and could not find the dimple on the timing gear, took out a spark plug #1 and hand cranked, piston is not moving but the hand crank turns. It's been about 6 months since I got the engine back from the rebuilder. Should I take out plugs and remove starter, oil the cylinders and then try again?

Mark Underwood
Gig Harbor, WA

Re: New Rebuilt Engine - Pistons not moving
 

MMMM So I take it the engine has not been fired since you got it back. I would pull the rest of the plugs and slowly hand crank again to see if all the pistons are in fact moving. Did you get a warranty from the builder? Best contact him before anything is removed to avoid any potential warranty issues.

Re: New Rebuilt Engine - Pistons not moving
 

Busted crankshaft? That would be odd,. Was the timing gear moving?

Re: New Rebuilt Engine - Pistons not moving
 

Yeah, put a flashlight in through the hole for the timing pin and see whether that gear is moving. That’s the most likely spot for problems. You can also put the car in gear and push it back and forth, see if the piston moves.

Re: New Rebuilt Engine - Pistons not moving
 

Are you sure you were looking at piston and not the valve? you could remove side timing cover and look to see if indeed timing gear etc are moving. Or like stated above push car in gear, might be just tight but you said couldn't find the dimple so i assume it is turning over.

Re: New Rebuilt Engine - Pistons not moving
 

Is the crankshaft nut just turning inside the crankshaft? Stripped threads in the crankshaft snout?

Re: New Rebuilt Engine - Pistons not moving
 

That would be a rare find!

Re: New Rebuilt Engine - Pistons not moving
 

Pistons not moving is also rare:)

Re: New Rebuilt Engine - Pistons not moving
 

If the piston is near the top or bottom it takes quite a bit of crankshaft movement before the piston moves a lot. I think you need to re-check this, the crank turning with no piston movement on a rebuilt engine is really pretty close to an impossibility unless it was gross incompetence by the builder. Even gross imcompetence really doesn't cover that bad of an error.

Re: New Rebuilt Engine - Pistons not moving
 

A broken crank is certainly less rare than that part being stripped completely.

Re: New Rebuilt Engine - Pistons not moving
 

A broken crankshaft on a newly rebuilt engine that hasn’t run. That would certainly be a rare occurrence!

Re: New Rebuilt Engine - Pistons not moving
 

A broken crankshaft is not at all unknown but as has been said, on an engine that hasn't even run????
I think we need to be looking elsewhere.

Re: New Rebuilt Engine - Pistons not moving
 

Well one thing for sure, it will be interesting what gets found.

Re: New Rebuilt Engine - Pistons not moving
 

Take the small timing cover off be aware there is a oil pan bolt up from underneath , When you turn the crank you can see if the timing wheel rotates . This is a very very odd never ever heard of this before .

John in rare sunny morning Suffolk County England .

Re: New Rebuilt Engine - Pistons not moving
 

Pull the oil fill tube out and you can see the crankshaft you may need a flashlight you will be able to see the crankshaft moving or not moving

Re: New Rebuilt Engine - Pistons not moving
 

perhaps it is stuck valves, they are more visible through the spark plug hole, there still isn’t a reply from the original poster

Re: New Rebuilt Engine - Pistons not moving
 

I would not take anything apart just yet. As others have said, a piston not moving is highly unlikely. Remove all four plugs. Normally you would do this to inspect the plugs prior to timing. Now the engine should turn over easily. Hold you thumb down on one of the spark plug holes and have someone hand crank the engine a few turns while the thumb is in place against the hole. If no resistance is felt get in touch with the engine builder. If you start removing parts your engine builder will probably be hard to deal with.

Re: New Rebuilt Engine - Pistons not moving
 

Any update ? A very strange issue you have there !

Re: New Rebuilt Engine - Pistons not moving
 

Weird. Is the pulley in front moving when hand cranking? Maybe the hand crank is not engaging correctly? I am also interested in learning what is found.

Try turning the engine over with the flywheel ring gear and a screw driver, or the starter.

Re: New Rebuilt Engine - Pistons not moving
 

The OP has only 2 posts. Is this thread serious or is he just stirring us up?