No start after timing chain replacement

[IL Duckshewter]

I have a 1995 4.0 with 267k known miles, I've owned since 58k miles. (odometer gear was bad for about a year). I have recently dropped the transmission (M5OD) and raised the motor enough out of the motor mounts so that I could remove the oil pan and replace the leaking stock gasket. While doing this, I also decided to replace the front crank seal and rear main seal, water pump, and timing chain components and timing chain. When I removed the timing chain, I made sure that I had both of the timing marks at 12 o'clock, which once removed, noted that both the crankshaft and the camshaft had key ways cut in them that matched the timing marks on the sprockets. Also of note, my motor takes the crankshaft sprocket that has the "knob" on the back side of the timing mark that engages the crankshaft keyway when installed. The kit that I purchased came with a sprocket that didn't have that "knob", and instead had a cutout in it so that it would slide over the woodruff key that the harmonic balancer attaches to. When I went to torque the camshaft bolt, I noted that the camshaft turned approx 90 degrees clockwise during this process, but the crankshaft didn't turn with the crankshaft sprocket. That's how I learned I had the wrong sprocket. Was able to get the right sprocket by ordering a kit for a '93 4.0, the only difference between the 2 is the crankshaft sprocket. I turned the camshaft sprocket back to 12 o'clock by going counter clockwise so that my keyways were both back in the 12 o'clock position. Attached the new sprocket, sealed everything back up and when I went to start it, I get nothing. It also sounds different when trying to start it now, like its all starter motor. I will get an occasional backfire, but no fire of the engine. I had pulled all of the plugs and hand turned the motor using the harmonic balancer to make sure I had everything back in place and it turned very easily by hand, no hard stops. I'm at a loss. I'm positive that the crank was not turned nor was the camshaft turned independently of each other without me knowing. Anyone have an idea? Is is possible that when I lifted the motor, I pulled the ground wire from the firewall and that is keeping me from starting?

 

[ShhhhhDougsHere]

I'm a big novice here.
All I can say is to ask you if have a EVTM for your truck?
Or know anything about them?
EVTM stands for Electrical and Vacuum Troubleshooting Manual.
If you do not have one you can most likely find 1 for sale on eBay.

I wish you luck.

 

[ShhhhhDougsHere]

I talked about the EVTM because I'm thinking that 1 of 2 things are wrong.
1 you've got your motor out of time in some way.
But from what you've already wrote it seems to me like your sure that's not the problem.
2 you've moved some wires around and something's not connecting properly.

 

[19Walt93]

The cam sprocket mark should be at the 6 o'clock position while the crank gear mark is at 12 o'clock to be timed properly. It's possible to do it with both marks at 12 o'clock but it would be real easy to miss by a tooth or 2. I'd check the compression first to confirm but I'm afraid it's got to come back apart.

 

[IL Duckshewter]

Looked at it with a camera, #1 was TDC of the compression stroke and the Intake valve was open. Took it apart and confirmed our suspicion, it was way out of time. I'll try and attach a photo that shows it, but what I found was that the crankshaft sprocket had moved and the knob on the back was not in the keyway of the crankshaft. How this happened is beyond me. My best guess is that I didn't have the chain properly tensioned and this slop allowed for the chain to move the sprocket enough to pull it out of the keyway. Anyway, problem solved, I'll get it all put back together Tuesday evening and see if it will start. I appreciate the offered suggestions! In the first photo you can see the key in the crankshaft. The second photo shows the knob that should be in the key of the crankshaft and it isn't.

 

[IL Duckshewter]

Follow up, so guys like me who look for help here can find it. In the process of putting the harmonic balancer back on during the first time, I used a dead blow hammer to tap it onto the crankshaft far enough to get the bolt to grab, then I used the bolt to push it the rest of the way on. DO NOT DO THAT! The taps, even though they were light, were apparently enough to get the crank sprocket out of place enough so that when I tightened down the bolt the tab was pressed against the crank snout, but not within the keyway. I highly suggest that you push the harmonic balancer on by hand and then use a longer bolt to push the harmonic balancer onto the crankshaft until you can finish the job with the correct bolt. Also, for reference, the harmonic balancer, when seated properly on the crankshaft, will hold the crank sprocket in place. I placed this on before I put on the timing chain cover to confirm and then I took a measurement from the front edge of the oil pain to the back edge of the harmonic balancer (the side closest to the timing chain cover on the part where the belt goes). This measurement was 2 11/16". I then pulled the balancer off, installed the timing cover, making sure that the cam sprocket was correctly in the keyway before closing it up, then I pushed the harmonic balancer on like I described above and confirmed proper placement by making sure that my measurement was 2 11/16". From there it was smooth sailing getting everything back on.....well maybe not the fan onto the water pump, but I prevailed. She fired right back up and hopefully I get another 270k miles out of the front and rear crank seals, oil pain gasket, water pump and timing chain components!