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I’ll give you a head’s up on the possibilities if it has no (or very low) compression. Best case would be that the cam timing is off, and fixing that resolves it. Worst case is that valves are bent on all the cylinders with no compression. If they have some compression (even 30 or 40 PSI) the valves aren’t bent.

With the valve covers off, see if any rocker arms are very loose. If they are, valves are almost for sure bent. It’s more common for intake valves to bend, because they’re bigger and usually stick down more when they’re open.

We’ll keep our fingers crossed and hope it’s not that.
 

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Discussion Starter · #22 ·
If the valves are all bent, presumably that means new head(s)? Would a problem bending the valves make some sort of awful sound? The first time I cranked it, and the last time, it has sounded exactly the same and never made any "bad" (banging/grinding/popping) sounds. More like the lack of sound, really sounds like mostly just the whirring/buzzing of the starter.
 

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The rocker tick is louder than valve crash would be. The good news is, your chain can be several links off and still not crash valves. It will run with up to 30 degrees (maybe more, but I'm not trying to find out) offset on a single head and have no symptoms other than a severe lack of power.

When you open the covers, turn the crank to TDC and look at the phasers and make sure you have lines and arrows where they should be. Lines in center on right/rear head and arrows on left/front. Make sure the dot on the phaser collar lines up close to the one on the cam. (It won't be perfect, but should be close. Mine is directly beside.) There are other holes the key pin can fall into, so use these dots to make sure you're in the key hole and not an oil hole. If you got them backwards, you should be fine. It would put the cams about 170 degrees out of phase with the crank, which means mechanically it would be operating almost like normal, but the pulses for the spark and fuel timing would be happening at the wrong times. The valves might have a bit of overlap in this scenario, which would explain your seeming lack of compression during starting.

And a bit of cost saving advice, reuse your old valve cover gaskets without applying RTV until you get the problem sorted, then put your fresh gaskets on. You won't leak much oil doing start attempts.
 

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Discussion Starter · #26 ·
The rocker tick is louder than valve crash would be. The good news is, your chain can be several links off and still not crash valves. It will run with up to 30 degrees (maybe more, but I'm not trying to find out) offset on a single head and have no symptoms other than a severe lack of power.
I really hope I didn't screw up the valves. I'll find out tomorrow.

When you open the covers, turn the crank to TDC and look at the phasers and make sure you have lines and arrows where they should be. Lines in center on right/rear head and arrows on left/front. Make sure the dot on the phaser collar lines up close to the one on the cam. (It won't be perfect, but should be close. Mine is directly beside.) There are other holes the key pin can fall into, so use these dots to make sure you're in the key hole and not an oil hole. If you got them backwards, you should be fine. It would put the cams about 170 degrees out of phase with the crank, which means mechanically it would be operating almost like normal, but the pulses for the spark and fuel timing would be happening at the wrong times. The valves might have a bit of overlap in this scenario, which would explain your seeming lack of compression during starting.
Yikes. I could definitely see that being screwed up, which would suck. I should still have the paint marks to double check everything, but this being off 170° sounds very plausible because I, stupidly, used the key pin on the cam & phaser to line up and didn't pay attention to the dots on the collar because they're tucked back too close to the firewall to really see w/o a mirror on the right exhaust cam. I'll be checking the two right cams first after doing a compression check.

If this is the case, and one of the cams (or both?) are off 170° would would there be any piston/valve contact? Or would I have gotten really lucky?

And a bit of cost saving advice, reuse your old valve cover gaskets without applying RTV until you get the problem sorted, then put your fresh gaskets on. You won't leak much oil doing start attempts.
That is great advice! I'm also looking at doing things in a specific order. Before pulling the valve covers at all, I'm going to do a couple other checks.
First, I'm going to do wiring checks on the fuel pump and fuel pump relay.
Next, I'll pull the upper intake and do a compression test on each cylinder.
Depending on what I find on those will likely determine if I open either or both of the valve covers.
When I put things back together, I'm not going to put the stupid brackets back on the upper intake after torquing until I know the thing is running, those two in front by the radiator, a/c lines, and upper radiator hose are a pain in the butt!

I'll be taking a lot of pictures this time. Last time all I did was snap a quick video of the bad rocker arm before taking off the cam. It was an exhaust valve on cylinder 5.
 

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Thank you! I fought with that decision too. I've done some work on this motor before, but never to the valvetrain. Good luck with your decision. I was kinda rushed into this. I took the van in for an oil change and they cracked the oil cooler and denied any fault. It was literally spewing oil all over so I had to either get it fixed, or fix it myself. The dealer wanted over $1k for the oil cooler job so I was tearing in to do that myself (that's a relatively easy job) and figured since I was tearing in already, might as well get rid of that tick and do that work myself too. I ordered up all the parts and dove in. I found one of the exhaust rockers on the right bank that was completely shot so I'm confident that was the tick I had, but with re-assembly, I'm just hoping I didn't screw something up that I can't easily fix myself. I replaced all 24 rockers/lifters and took my time over a couple days. I'm an engineer, but not a mechanic. I wrote out torque specs/order, and any time I second guessed anything, I'd stop and investigate. The two hardest part of the job for me (aside from the current non-working state of things) was getting tension released properly on the right bank. The tool I bought didn't seem to want to give me much play on that chain and the intake cam was a little difficult to get in and out. I took my time, and things seemed good when I put it back together, but something is definitely wrong. I am leaning toward some sort of compression problem based on the advice here, symptoms themselves, and watching a couple other videos for similar sounds to the way it's cranking. It sounds so "loose" I thought the starter solenoid wasn't actually engaging the motor, but I can see the serpentine belt (and pulleys) move when it cranks, it just sounds so "free" like the motor isn't even doing anything so maybe some valves are stuck open, but it's an interference motor, so I don't know what exactly could be going on.

I'll report back what I find out, but I already ordered another valve cover gasket set and will tear back in this weekend to see if I can figure anything out. The local shop wanted $2900 to do this job, so I'm fine spending another $50 on the mahle gasket set and tearing back in for now. I was about $600 in, for quality replacement parts (mopar oil cooler (and new sensors), mahle gaskets, melling rockers/lifters, $20 chinese cam/timing blocks from amazon) and now an additional $42 on another gasket set, and for the heck of it I bought a OTC compression tester that will be here tomorrow to add to my toolbox. Another reason I'm willing to keep fighting this is I bought a second vehicle with this motor recently, so I'm considering any learnings I get as an investment.
I’ve been working myself up to do this task as well. I pray yours comes to a positive conclusion and I appreciate hearing your story. (I was planning to follow the motor city mechanic video as well)
 

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First, I'm going to do wiring checks on the fuel pump and fuel pump relay.
You said you hear the fuel pump run “when you put the key in”. I assume you mean when you turn the key to on (which is when the pump runs for a couple seconds to prime the system). If you’re sure, there’s no need to check anything else with the wiring. It could run and have no fuel pressure, but that doesn’t seem likely.
 

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You said you hear the fuel pump run “when you put the key in”. I assume you mean when you turn the key to on (which is when the pump runs for a couple seconds to prime the system). If you’re sure, there’s no need to check anything else with the wiring. It could run and have no fuel pressure, but that doesn’t seem likely.
I haven't looked under the hood recently, but most cars, it is possible to disconnect the fuel line from the fuel rail, and just flip the key to aux to see if fuel squirts into a container. As you disconnect, there should be fuel squirting out, which is a good sign that it did work- - if the line is dry, then there is a problem.
 

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...
If this is the case, and one of the cams (or both?) are off 170° would would there be any piston/valve contact? Or would I have gotten really lucky?
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The piston would be very close to the same position as if things were normal (180 degrees would be exact). You should be within the 30 degrees that I know it can be out without contact.
 

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Discussion Starter · #33 · (Edited)
I have a reason for my no-start condition, and more questions.

First I removed the upper intake manifold and all the intake stuff, checked all the wiring and everything looked good. Then I pulled off the fuel injector connectors, ignition coil wires, and pulled the fuel pump fuses. I did a cold compression test, and have exactly 0 compression on all cylinders.

I opened the left bank valve cover again, and everything looks right. I then tried thinking of what could give zero compression on all cylinders and while I was looking at things, thought maybe the valves were never able to fully close. I put the timing chain cam phaser blocks back in on this side after aligning the timing marks, removed the intake cam, and could see that as I was loosening the bearing caps the cam was moving up slightly (after rotating inward 30° to the "rest position", which didn't feel as "loose" as when I was taking out the old rockers/lifters). Then I pulled one lifter and compared against the old ones and my problem was painfully obvious, I didn't even have to get out calipers. I have the wrong lifters. The new ones are probably ~2mm too tall. I checked the order from rockauto and their part selector gave the correct JB7525, but they sent me JB7524 and I didn't notice. I also didn't compare when changing them over because I pulled all 6 for one cam out, set them aside, while the new ones soaked in oil before I installed them. They seem like they're the same diameter, but the wrong ones are taller.

On to the questions:
1. Does this seem like the "smoking gun?" I believe yes.
2. Do you think having these in could have caused any additional damage to the cams, new rockers, cam bearing caps, etc.?
3. Do you think this could have caused any valve to piston contact? (I do have a borescope coming today from Amazon and can look to see it the pistons have any visual markings)

Wood Gas Jewellery Asphalt Auto part

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Discussion Starter · #34 ·
I forgot to mention, I definitely had fuel pressure because even with the fuses pulled for the pump for a while, when I was putting the wedge to release timing chain tension on the left bank, the fuel line was in the way and when I disconnected it from the fuel rail gas literally shot all over. 🤦‍♂️
 

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Discussion Starter · #36 · (Edited)

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Big screw up on RockAuto's part. I doubt it caused any damage because this would lessen the amount that the valve extends into the cylinder. Zero compression was probably because the intake valves couldn't open, but the exhaust could.
 
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Discussion Starter · #38 · (Edited)
Big screw up on RockAuto's part. I doubt it caused any damage because this would lessen the amount that the valve extends into the cylinder. Zero compression was probably because the intake valves couldn't open, but the exhaust could.
I own a little bit for not double checking that they shipped what I ordered, too.

The wrong lifters were the taller ones, wouldn't that make the valves open more, not less? My fear is that the increased angle of the rocker could wear into the cam a tiny bit, and/or the extra 2.2mm of height (I measured with calipers) caused the valves to open a little deeper into the cylinder.

I'm guessing since it never actually ran just spun a few times, it's probably ok.

Senile and others, thank you for all the help! I really appreciate it!
 

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Lifters are on the opposite side of the valves on the rocker...so a longer lifter should mean a shorter valve travel stroke - thus no compression when "closed".
No pushrods in this engine?
 

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That’s a real bummer. You’re right — the valves would have opened another 2 mm (times the ratio of the rocker arm). You’re just going to have to get it back together and see what you have. The only way to test for bent valves is a leakdown test, and you can’t do that with the timing chains unhooked.

All it takes is two crank revolutions to bend the valves on every cylinder, so it’s wishful thinking that you only cranked it a bit. I’m hoping for the best for you.
 
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