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I realize this post is long since dead, but thought I would post this in case it helps someone else out. You can ABSOLUTELY do a head replacement on the 4.7 Durango without pulling the front timing cover, if you are very careful and think it through. Just finished one tonight. I zip-tied the cam sprocket to the timing chain (so it couldn't jump), while still attached to the cam, and then used wire to tie the sprocket to the hood through the large square hole on the interior side of the hood - this kept tension on the sprocket so that the chain could not fall. I then pulled the head bolts (10 large, 4 small at the front), took everything apart, pulled the camshaft sprocket bolt and the two timing guide bolts, and braced the head up about four inches. This let me access the chain from underneath the head, where I ran fishing line through the chain on each side (tricky but can be done) and tied it tight to a small wood dowel slid across the head (UNDER the old head gasket against the block - don't forget you need to remove that gasket), parallel in front of the chain. Once the chain was secure this way, I could untie the cam sprocket wire from the hood and let the cam sprocket go loose (the zip tie still holding it's orientation to the chain, the dowel and fishing line preventing the chain from falling into the engine). This gave me more room to slide the head out, and let me lift the head the rest of the way off. Tip - undo that *&#$ing ground strap that's hidden waaay on the back of the left head first!! ;)

Make sure you don't rotate the cam at all while the head is out, in order to keep the alignment!

When I put it back together, I put the new head gasket in and put it on the rear alignment pin, lifted the head back on over the slack chain, lined up the exhaust and the rear alignment pin, fed my sprocket wire through the head and tied the cam sprocket wire back to the hood (which tightened the chain for alignment of the sprocket with the cam once the head is down all the way) and then cut away the fishing line, removed the small wooden dowel, slipped the gasket over the front alignment pin and dropped the head into place. Cam sprocket went right back on the cam no problem.

Worked like a charm and saved me about a zillion headachy hours - I don't do this crap for fun so the LESS I gotta do on this nightmare the better! Hope it saves someone, somewhere, from having to rip the entire front off the engine - once you've done this job once or twice, you can actually do it in a couple hours, it's really not that bad and first time is by far the worst.
 

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I realize this post is long since dead, but thought I would post this in case it helps someone else out. You can ABSOLUTELY do a head replacement on the 4.7 Durango without pulling the front timing cover, if you are very careful and think it through. Just finished one tonight. I zip-tied the cam sprocket to the timing chain (so it couldn't jump), while still attached to the cam, and then used wire to tie the sprocket to the hood through the large square hole on the interior side of the hood - this kept tension on the sprocket so that the chain could not fall. I then pulled the head bolts (10 large, 4 small at the front), took everything apart, pulled the camshaft sprocket bolt and the two timing guide bolts, and braced the head up about four inches. This let me access the chain from underneath the head, where I ran fishing line through the chain on each side (tricky but can be done) and tied it tight to a small wood dowel slid across the head (UNDER the old head gasket against the block - don't forget you need to remove that gasket), parallel in front of the chain. Once the chain was secure this way, I could untie the cam sprocket wire from the hood and let the cam sprocket go loose (the zip tie still holding it's orientation to the chain, the dowel and fishing line preventing the chain from falling into the engine). This gave me more room to slide the head out, and let me lift the head the rest of the way off. Tip - undo that *&#$ing ground strap that's hidden waaay on the back of the left head first!! ;)

Make sure you don't rotate the cam at all while the head is out, in order to keep the alignment!

When I put it back together, I put the new head gasket in and put it on the rear alignment pin, lifted the head back on over the slack chain, lined up the exhaust and the rear alignment pin, fed my sprocket wire through the head and tied the cam sprocket wire back to the hood (which tightened the chain for alignment of the sprocket with the cam once the head is down all the way) and then cut away the fishing line, removed the small wooden dowel, slipped the gasket over the front alignment pin and dropped the head into place. Cam sprocket went right back on the cam no problem.

Worked like a charm and saved me about a zillion headachy hours - I don't do this crap for fun so the LESS I gotta do on this nightmare the better! Hope it saves someone, somewhere, from having to rip the entire front off the engine - once you've done this job once or twice, you can actually do it in a couple hours, it's really not that bad and first time is by far the worst.

My advice to anyone reading this... Do NOT follow the advice above! This is a short cut that will lead to premature timing chain / guide wear.

The reason I say this is because there is no way to properly re-set the tensioners after they fully extend.

After you removed the cams/cam sprocket the chain became lose which allows the tensioners to fully extended... how do you compress them back and hold them in place while you reinstalled the guides, chains and cam sprockets?

I am not trying to start a flame... I am just pointing out a really bad shortcut that will lead to issues sooner than later.

Although you did get it all back together... I just dont see any way you where able to insure the tensioners where set properly after everything was tightend up. Once the tensioners extend, compressing them back down is an involved process that requires either a vice, channel locks or really strong fingers... and sticking a pin in a little hole to hold them down until the timing set is fully installed. the pins holding the tensioner down are pulled LAST before timing cover/valve covers are installed.

The tensioners are the last part that is set/released after the entire timing set is installed... they are designed to keep the proper tension on the guides/chains allowing hundreds of thousands of miles out of the guides and chains.

Again, although it is possible to get it all back together... its not back together correctly. Sure it runs... but your timing set is currently on an accelerated wear schedule.

I hope this makes sense...Sometimes shortcuts are only long-cuts disguised as shortcuts.

If anyone has any questions or concerns about doing a 4.7L timing set, please dont hesitate to contact me. I have done more than a hand full of them. We know a few tricks and tips as well to help it go smoothly... But to do it correctly, that timing cover must come off!

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