Replaced engine. New engine won't turn over.

[Joe_in_GA]

My kids ran my engine out of oil in my '06 Mazda5. I had to replace the engine; one of the piston rod bearings was shot. I bought a used engine and installed it, but now it won't turn.

I could turn the crankshaft before I bolted on the automatic transmission. I could turn it after the transmission was bolted on. I could turn it with the driveshafts installed but not hooked up to the steering knuckles. I didn't check it after they were fully installed. Now that It's put back together, the engine won't turn.

The starter didn't turn it. I can't turn it by hand either like I could before. I removed the starter, thinking it might be jammed, but that's not it.

I am flummoxed. Any ideas?

Thanks.

 

[Secondtyme]

What year 5 was the donor engine from? Could it be the immobilizer? How much of the original engines electrics did you swap over to the "new" engine?

 

[Joe_in_GA]

It's the same '06 model year. The only stuff I swapped was the alternator, starter, and a/c compressor.

 

[rodslinger]

My kids ran my engine out of oil in my '06 Mazda5. I had to replace the engine; one of the piston rod bearings was shot. I bought a used engine and installed it, but now it won't turn.

I could turn the crankshaft before I bolted on the automatic transmission. I could turn it after the transmission was bolted on. I could turn it with the driveshafts installed but not hooked up to the steering knuckles. I didn't check it after they were fully installed. Now that It's put back together, the engine won't turn.

The starter didn't turn it. I can't turn it by hand either like I could before. I removed the starter, thinking it might be jammed, but that's not it.

I am flummoxed. Any ideas?

Thanks.

You mentioned you could turn the motor by hand after installing the transmission. But was this before or after connecting the torque converter? Pull off the serpentine belt to make sure none of the accessories locked up too. I would always start simple. Maybe something just bound up after tightening all the bolts down. What part of Georgia you in?

 

[Joe_in_GA]

This is what I have done so far: I pulled the starter: no luck. I pulled the axles one at a time: nope. I took off the serpentine belt: no. I took off the a/c belt: nada.

I live out west near Villa Rica.

 

[Joe_in_GA]

The weird thing is it worked fine as I was installing it. I hooked up the transmission with the converter installed. I had to turn it to bolt the converter up. It worked after that no problem. I'm not sure when it locked up, because I had no reason to turn it anymore after the transmission was connected.

 

[Secondtyme]

Maybe the trans is the issue, not the new engine. Was the car in gear, or in motion, when the OE engine let go?

 

[thaxman]

Did you connect the battery at all? Is it possible the torque converter went into lockup mode? Torque converters are supposed to spin freely or else an engine couldn't idle, and yet your powertrain is frozen. Could the converter have been damaged or the shaft bent somehow in removeal/installation or when the kids drove it w/no oil?

 

[Joe_in_GA]

Sorry for being absent. This is what I've done up to now: I removed everything I mentioned above, but I couldn't figure it out. So, I pulled the transmission off completely. Everything spins fine. I reinstalled the transmission, and it worked, sort of. When the engine started, the starter wouldn't disengage completely. It made a horrible grinding noise.

I started measuring things, and the gap between the torque converter and flywheel are different. The gap on the new engine between the flywheel and the engine is about 1/8" longer. So, what's happening is the flywheel is warping towards the engine when I tighten it down. I tried swapping flywheels, but that doesn't change anything.

So, I am at an impasse. I'm thinking I might need to return the engine and get another one.

Okay, to answer a few of the questions: the transmission never had any problems. The old engine has not blown up yet, but I know it could go at any time. I've had this problem before in another car. So, I decided to fix it before I had to have it towed it 40 miles home and call out from work.

 

[rodslinger]

Sorry for being absent. This is what I've done up to now: I removed everything I mentioned above, but I couldn't figure it out. So, I pulled the transmission off completely. Everything spins fine. I reinstalled the transmission, and it worked, sort of. When the engine started, the starter wouldn't disengage completely. It made a horrible grinding noise.

I started measuring things, and the gap between the torque converter and flywheel are different. The gap on the new engine between the flywheel and the engine is about 1/8" longer. So, what's happening is the flywheel is warping towards the engine when I tighten it down. I tried swapping flywheels, but that doesn't change anything.

So, I am at an impasse. I'm thinking I might need to return the engine and get another one.

Okay, to answer a few of the questions: the transmission never had any problems. The old engine has not blown up yet, but I know it could go at any time. I've had this problem before in another car. So, I decided to fix it before I had to have it towed it 40 miles home and call out from work.

Anytime I've encountered an issue like this it was because the torque converter wasn't seated fully into the transmission pump shaft. With the trans out turn the converter by hand one or two full turns while pushing in and see if it drops in another 1/4 to 1/2". And I can't say I haven't done this myself.... Flywheel on backwards? There are usually items by design to prevent that but it has happened.