Rebuilt motor isn't running right.

[xjtrailrider]

Check all of the grounds. Just for giggles run an extra ground from the batt to the chassis.

 

[stroked88]

Just for confirmation,you should pull the distributor cap and bump the motor over to tdc on the compression stroke and take a picture of where the rotor is pointing. im sorry to throw this in there again, but it sounds incredibly similar to when i had my distributor in and it was retarded by 1 tooth

 

[xjtrailrider]

Just for confirmation,you should pull the distributor cap and bump the motor over to tdc on the compression stroke and take a picture of where the rotor is pointing. im sorry to throw this in there again, but it sounds incredibly similar to when i had my distributor in and it was retarded by 1 tooth

He swears he has it set right but I have sworn that I had the indexing correct too only to find it off a tooth when I re-checked after rechecking LOL!

Its so easy to get it off one tooth either way.

 

[stroked88]

He swears he has it set right but I have sworn that I had the indexing correct too only to find it off a tooth when I re-checked after rechecking LOL!

Its so easy to get it off one tooth either way.

my dad swore up and down that he had my dizzy in right after he help me build my stroker, went to fire it up, wouldnt run worth a damn, and didnt get to break the cam in properly. i yanked the distributor, advanced it a tooth, and it started right up and ran fine. unfortunately since we didnt get to break the cam in properly it had to come back out, but i knew for next time!
Edit: my dad isnt just some wanna-be, he's built just about any motor i can think of atleast once. He did a lot of custom race engines for IMCA modifieds, so he knows his stuff. BUT! he trusted a chiltons manual for indexing the dizzy... i had read on here how to do it but he wouldnt listen because i was only 16 at the time, and this was "just a bunch of guys on the web" to him lol.

 

[JeepManDan]

Well i've tried it where it's supposed to be, and a tooth both ways. Just for kicks, i'll get a picture a little bit later.

Also, I ran a ground from the battery to the fender. It didn't make a difference.

So then I re-checked my codes. Now it's getting a code 11. No signal from the CKP sensor. Now i'm going to throw a new sensor on and see where that'll get me.

 

[JeepManDan]

Alright, I think I just about have this thing figured out. I tore the valve cover off to re-check the cam timing and guess what i didn't see. Oil. Looks like the oil pump in this motor didn't work or it got damaged during re-assembly, which isn't getting oil to the hydrolic lifters which isn't allowing my valves to open all the way. Who'd of thought...

 

[xjtrailrider]

Alright, I think I just about have this thing figured out. I tore the valve cover off to re-check the cam timing and guess what i didn't see. Oil. Looks like the oil pump in this motor didn't work or it got damaged during re-assembly, which isn't getting oil to the hydrolic lifters which isn't allowing my valves to open all the way. Who'd of thought...

You got lucky that it "didn't" start.

 

[Talyn]

He said it did start and run, but poorly. Did you not prime the engine prior to firing and watch for oil at the push rods?

 

[Motornoggin]

He said it did start and run, but poorly. Did you not prime the engine prior to firing and watch for oil at the push rods?

That's exactly what I thought. It should have had oil up there before he started it.
When I rebuilt my 4.0, I primed it, fired it up and promptly had to shut it off, as I had no oil pressure. I chased it for a bit, and finally connected a gauge right to the port. Suddenly, I had pressure! Turns out, my sending unit chose a most inopportune time to fail. :doh:

 

[xjtrailrider]

He said it did start and run, but poorly. Did you not prime the engine prior to firing and watch for oil at the push rods?

Yes dang it! I should re-read older posts before answering.

That's exactly what I thought. It should have had oil up there before he started it.
When I rebuilt my 4.0, I primed it, fired it up and promptly had to shut it off, as I had no oil pressure. I chased it for a bit, and finally connected a gauge right to the port. Suddenly, I had pressure! Turns out, my sending unit chose a most inopportune time to fail. :doh:

This happened to me on my MJ, what a crazy time for a sender to die.