2001 Dodge Durango 4.7L

I have 2001 Dodge Durango 4x4 SLT, with the 4.7L vin code "J". One of the pistons blew on it. I was able to retrieve another short block for it. Changed the heads over, bought a complete new timing kit for it (Sprockets and chain), new spark plugs as well. Truck ran fine before the piston blowing. Heads had no damage. All is put together, car will crank, but not turn on. The crank sensor i believe is good, because if i manipulate it when its loose, it clicks on the fuel pump relay and others in the fuse box. Could it be that the reluctor inside the block is different then original? Is there another route i should go before i throw in the towel and get another motor? Any response would be greatly appreciated. Love your videos Also, BTW, im 120% sure it was put correctly and put in time. Before i put cover back on, i manually spun the motor and it falls back to all the appropriate marks. Also put a new head gasket and other new gaskets as well...
Let me know if there's another diag I may need to do for further clearing.....

Basically, one good question to know the answer to is does Chrysler use different reluctors for different 4.7 blocks? Because that reluctor is part of the block...

Hey Kevace1! I'm not sure if there were different reluctors in use on these 4.7's, but we can check. Noah may have the answer to that one.

Do you happen to know the year/make/model the donor short block came from? I know that Dodge/Chrysler/Jeep switched from their PCM designs from what was called JTEC to NGC in the early and mid 2000's. The crank and cam reluctor designs changed, too. Check out this article from John Rogers on just such a case .

In the mean time, I'd suggest starting out with the basic checks for spark, injector pulse and fuel pressure. Knowing which one you're missing will help point us in the right direction. Here's a great ScannerDanner video for checking spark and injection pulse with an incandescent test light. It's on a Honda, but the basic concepts are the exact same.



Get back to us with what you find, and we can figure out the next step.

Thanks Tyler for the info...spark will be my next check hopefully tomorrow if i get home early enough from work. But a note to add; im not sure where i got it from, im assuming from where i retrieved the short block from, i have a another crank sensor that is different then the one originally from my truck, and it plugs right in to the socket for my crank sensor, but it does not fit onto the block. Its held in by one bolt, and this different sensor was shorter compared to the original sensor... Maybe from the NGC PCM. IDK, but i know mine is a JTEC, i have 3 plugs on my PCM not 4 as in NGC.

BTW, read the article by John Roger's, really hope that didnt happen to me, but hoping the cam sensor design i mention is an indication of i have the right block. The link you mentioned about finding spark with incandescent test light didn't show



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Kevace1 wrote: BTW, read the article by John Roger's, really hope that didnt happen to me, but hoping the cam sensor design i mention is an indication of i have the right block. The link you mentioned about finding spark with incandescent test light didn't show

It didn't? Crap... Maybe try this link:

BTW, read the article by John Roger's, really hope that didnt happen to me, but hoping the cam sensor design i mention is an indication of i have the right block.

Yeah, sorry about that, I really didn't mean to worry you! I've been trying to think of a way to know for certain which tone wheel we're working with, JTEC or NGC. From what I'm reading, the NGC design has around 32 teeth on the crank wheel, while the JTEC has around 16. It'd be a lot of work, but you could pull the crank sensor, mark the tone wheel, and count the number of teeth in one full revolution. :huh:

That little bit is very helpful. I will count the teeth on the old block and check and do the same to the new block. Thanks again tyler.....you did/are kinda scaring me.....but i guess i can only blame my own ignorance for this little misshap if it is the root cause, as i cant really find out where the donor motor came from

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Kevace1 wrote: That little bit is very helpful. I will count the teeth on the old block and check and do the same to the new block. Thanks again tyler.....you did/are kinda scaring me.....but i guess i can only blame my own ignorance for this little misshap if it is the root cause, as i cant really find out where the donor motor came from

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No problem! As an alternative, if you have a DVOM, you could probe the CKP signal wire while turning the engine over and watch for how many 0-5V transitions you see. Mark the crank balancer for your 360 degree reference. Not sure if this would be less or more work, just an idea.

I'm sorry, I'm not familiar enough with these engines to know the difference externally, or if there even is an external difference. :blink:

Looks like I'm late to the party, lol!
I don't understand how the reluctor is part of the block? I'm gonna have to look into this one a little further, I never noticed that feature of these motors.
As a rule of thumb, with ANY Chrysler motor swap, I use the flywheel off the engine that came out of the car.
They just make too many different ones across the board, and change them at irregular intervals (IE in the middle of a production year).
If there's a mismatched reluctor issue, it should show in live data. Cam and Crank sync pids during cranking should always say "Yes" or "Synched" or some sort of positive conformation.

Noah wrote: Looks like I'm late to the party, lol!
I don't understand how the reluctor is part of the block? I'm gonna have to look into this one a little further, I never noticed that feature of these motors.
As a rule of thumb, with ANY Chrysler motor swap, I use the flywheel off the engine that came out of the car.
They just make too many different ones across the board, and change them at irregular intervals (IE in the middle of a production year).
If there's a mismatched reluctor issue, it should show in live data. Cam and Crank sync pids during cranking should always say "Yes" or "Synched" or some sort of positive conformation.

Yes, in this motor, as with the 3.7 V6 in the liberty and other vehicles, the reluctor is inside is inside of the block. I dont have a scope tool, i have not gone that advanced yet in my garage tool repertoire, but i will soon. I just personally love messing with different cars period. Ive never been a dodge guy really. But got this durango in clean shape and as a trade. Ive already confirmed the old old block has 16 teeth at the reluctor like Tyler said.. Ill make sure i take pics of the of block for you noah. The car now is at a friends garage, cause wife needed the garage empty for a concrete treatment she wants to do...the flywheel has now say on turn on.

On a side note, my friend was sayimg he was spending some time on the truck for the heck of it...and he said he would get .5v on the crank sensor sensor wire with key on, but when he told his partner to crank, he loses it completely.... Never to see it again. Ill have to confirm thats the wire he's talking about...not sure if that helps any.....forgot what SD mentioned about the 3 wire crank sensor in Chrysler's

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Here is the reluctor of the old block. I guess chrysler thought it was a good idea......not sure why. Waiting for my buddy to let me know when he has time if the new block has the same amount of teeth.....ill keep you guys posted

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Thanks for the update and pictures, sir!

I'd be very interested to follow up on that signal disappearing once you get the truck back.

Oh, I see. The reluctor wheel is mounted on the crankshaft internal to the engine.
I couldn't quite picture how it could be integrated into the block casting.

Sorry for the long wait guys.....but it has been confirmed....im the eternal retard...the reluctor on the rebuilt block has 32 teeth....it will never crank.....now to figure out what route to go now.....i already put plenty of new parts on the new motor.....uuuuggghhhhh

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Kevace1 wrote: Sorry for the long wait guys.....but it has been confirmed....im the eternal retard...the reluctor on the rebuilt block has 32 teeth....it will never crank.....now to figure out what route to go now.....i already put plenty of new parts on the new motor.....uuuuggghhhhh

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Don't be too hard on yourself!
Interchanging Chrysler engines can be tricky business! I've seen plenty of traps sprung three quarters of the way through an engine swap.

So, there's really only one solution to this problem, right? Change the engine again...
Or am I overlooking another simpler solution?

Noah wrote:

Kevace1 wrote: Sorry for the long wait guys.....but it has been confirmed....im the eternal retard...the reluctor on the rebuilt block has 32 teeth....it will never crank.....now to figure out what route to go now.....i already put plenty of new parts on the new motor.....uuuuggghhhhh

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Don't be too hard on yourself!
Interchanging Chrysler engines can be tricky business! I've seen plenty of traps sprung three quarters of the way through an engine swap.

So, there's really only one solution to this problem, right? Change the engine again...
Or am I overlooking another simpler solution?

That kinda rolled off the tongue pretty easily..... :rolleyes: :rolleyes:

I have already spent over $300 in parts for this motor already. Im internally debating just fixing the broken piston on the old block, the other option is another motor all together, but then what do i do with this one?? IDK.....im having a huge internal debate :confused:

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Is there any way you can get an exchange or refund on the engine?
Technically, it is the wrong engine...

That unfortunately is not an option....the rebuilt motor came with the truck...and i got it back in February... Now the guy wont answer any text.....but im not too angry...i traded him a 96 dakota ext cab with a bad tranny...just hate that I didn't know this little detail before putting the motor all together with new parts....im assuming just changing the computer probably wont be an avenue to go???

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cked ur basics fuel spark different shortblck after 2003 it has a different reluctor if timing rwong one tooth will not run

cesar.hernandez wrote: cked ur basics fuel spark different shortblck after 2003 it has a different reluctor if timing rwong one tooth will not run

Read a few posts back my friend.....i have a whole different issue now

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take cramk out exchange reluctors