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'05 Z71 Will Not Start After Maintenance

If the motor turns over and you haven't heard anything making contact, then you're probably ok but I can't say for sure if being 180 deg off nothing would collide. But yes, check fuel pressure first you should hear it running for a few seconds when you first turn on the key, then check it at the rail and also make sure you have spark.. Also go over every wire and connector and make sure all is good and connected, wouldn't be the first time something wasn't right after R&Ring parts..

Did you put on a new timing chain and gears?
 
If the motor turns over and you haven't heard anything making contact, then you're probably ok but I can't say for sure if being 180 deg off nothing would collide. But yes, check fuel pressure first you should hear it running for a few seconds when you first turn on the key, then check it at the rail and also make sure you have spark.. Also go over every wire and connector and make sure all is good and connected, wouldn't be the first time something wasn't right after R&Ring parts..

Did you put on a new timing chain and gears?
It turns over and I didnt hear any loud noises so I don't think anything is colliding. I did installed a new timing set:
Melling 48560T-9 High Performance Replacement Timing Set https://a.co/d/eApbc1r

The crank gear is a 2 piece with different slots for timing change and I did install it at the "0" slot which is supposed to leave it at stock settings.

Only things I unplugged were the front differential sensor, low oil sensor and the sensors in the hubs since I'm doing bearings. All is plugged back in aside from aren't on yet.

I did clean my MAF sensor with MAF sensor cleaner because I think some of the oil from my K&N intake got on it and threw a fuel ratio code.
 
I'm so lost now, because this is exactly what I did when installing the timing gears. Yes I turned them each independently, but from what I've read about LS engines 6 o'clock is exhaust and 12 o'clock is compression on the cam, and 12 o'clock is always TDC on the crank, so what did I do wrong?


There also seems to be quite the online debate as to whether or not a LS engine can be 180° out of timing, so that's not really helping my headache either. Too much of these questions are asked on discussions where distributor rotors come into play, so they're basically not overly helpful.

I am seriously wondering now if it's not a mechanical issue, but the computer expecting one stroke when the engine is at another. Maybe not a possibility, maybe it really is the gear on wrong I haven't written that off, but the idea did cross my mind.
 
Also, I believe there are many different timing gear sets for different year and series LS engines, and you may have the wrong one for your motor.. The bumps and/or notches on the gear pass over the sensor sending signals to computer so if it doesn't match your original then it would be a no go..
 
Also, I believe there are many different timing gear sets for different year and series LS engines, and you may have the wrong one for your motor.. The bumps and/or notches on the gear pass over the sensor sending signals to computer so if it doesn't match your original then it would be a no go..
According to Amazon, where I purchased it, and Summit Racing this one fits my year, model and engine code. So that's at least one question answered.
 
They were both pointed at each other, crank at 12 o'clock cam at 6 o'clock. I think what happened is that I rotated them both separately with the chain off (don't ask me why, i had a reason at the time that i cannot remember) and upon reinstalling the cam should have been at 12 rather than 6. I was thinking all that mattered was the timing marks, but it's obvious upon retrospect that the 2 different size gears spin at different speeds so there would be more to it.

Unless someone else has info that points me in another direction I'm going to take the timing cover off this week and reposition the cam then check to be sure the mark on the cam sprocket is where it's supposed to be on the Compression stroke. Just going to do the wad of shop towel in the spark plug hole trick to find compression.

Did get my fuel pressure gauge so could test that first, but pretty sure I messed up the timing.

Not sure if you can see the "key" (I think that you can) on the crank with the oil pump on, if you can and you can align pointing at the upward right angle in alignment with cylinder 1 (around 2 o'clock), then that is tdc for #1 (and the timing mark on the crank gear should be at 12 o'clock - if all is good). Then, not knowing where you turned the cam, (when/if all is good) the cam gear's locating dowel hole should be at 3 o'clock when the timing mark on the gear is at 6 o'clock.

When I've had to find tdc blind, I use a dowel in the #1 sparkplug hole and watch as I rotate slowly by hand once I get where I think is tdc then I back off a bit and back on again just to verify true tdc (watching dowel).
 
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Not sure if you can see the "key" (I think that you can) on the crank with the oil pump on, if you can and you can align pointing at the upward right angle in alignment with cylinder 1 (around 2 o'clock), then that is tdc for #1 (and the timing mark on the crank gear should be at 12 o'clock - if all is good). Then, not knowing where you turned the cam, (when/if all is good) the cam gear's locating dowel hole should be at 3 o'clock when the timing mark on the gear is at 6 o'clock.

When I've had to find tdc blind, I use a dowel in the #1 sparkplug hole and watch as I rotate slowly by hand once I get where I think is tdc then I back off a bit and back on again just to verify true tdc (watching dowel).
Just looked at a pic I took after install and the cam locating dowel is at 3. But now I realize what could be the issue and it's worse. The set I got has multiple slots for both advancing and retarding timing, and a 0 slot to leave it at stock. But I think the timing mark is right above that 0 slot, which means that if I aligned it there the Woodruff key (ironically my wife's maiden name) would also be pointed at 12 o'clock, not 2.

Now I may need to figure out how to get the oil pump off without removing the oil pan again and wasting 6 qts of fresh oil.
 
I've been following along with interest, but I have little to offer mechanically.

However, I feel that with a little proper planning and execution, you could drain and save any fresh engine oil and/or coolant.

I understand the desire to not waste any fresh fluids, but I think you could manage to minimize any loss, especially given all you have already accomplished.

I'm hoping for a quick and painless solution.
 
Just looked at a pic I took after install and the cam locating dowel is at 3. But now I realize what could be the issue and it's worse. The set I got has multiple slots for both advancing and retarding timing, and a 0 slot to leave it at stock. But I think the timing mark is right above that 0 slot, which means that if I aligned it there the Woodruff key (ironically my wife's maiden name) would also be pointed at 12 o'clock, not 2.

Now I may need to figure out how to get the oil pump off without removing the oil pan again and wasting 6 qts of fresh oil.
If you're not sure, then unfortunately you have to back in to be sure. It may be off so as there is no interference but enough that it's not going to run.. I went to the Melling catalog and yes, it looks like it the right part for a 05..

Good luck
 
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If you're not sure, then unfortunately you have to back in to be sure. It may be off so as there is no interference but enough that it's not going to run.. I went to the Melling catalog and yes, it looks like it the right part for a 05..

Good luck
Just confirmed it. The crank gear is on wrong. The old gears timing dot does not line up with the Woodruff key, it would be at 2 o'clock like it should be.

I'm really tempted to do this: rotate the engine by hand until the timing mark is at 2 o'clock, probably even doing the trick to find tdc which would be on the Compression stroke like it supposed to be, then remove the chain and cam gear and install that with the timing mark at 6. That would put the cam dowel at 3 and in theory all else would then be lined up. I could maybe make a little mark on the crank gear at tdc on 12 as well so that would become my new timing mark.
It'd be a head scratcher if anyone else opens this engine but I plan on keeping this truck until it dies of old age or gets totalled.
And yes, I my internal mechanic and OCD is saying I can't do that, it has to be a certain way. Someone tell me it would be wrong tho?



EDIT: After thinking it thru I now completely understand what I did and am rewriting this post. Not knowing that the woodruff key was to be at 2 o'clock I inserted it into the slot marked 0 on the gear and aligned, pointing the key at 12 o'clock. The key should have been in the -4 slot on the crank gear, which would have pointed the key at 2 o'clock when the crank and cam timing marks were lined up properly at 12 and 6 respectively and I would not have had this issue. In hindsight makes 100% sense. If I had looked at the old crank gear closely I would have noticed this as well and avoided the headache. Plus side, I guess, is the knowledge and understanding of timing on an LS engine that I've now gained. Downside is the hours I will now take to disassemble and reassemble the engine again, but at least I'm 100% confident this is the issue and I know what to do to fix it. And a big plus I didn't bend any valves etc.
 
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Sounds simple but if your just one tooth off then your cam with be advanced or retarded more than just a few degrees and you will not be pleased with the way it runs, if it runs.. DO IT RIGHT..
 
Got the timing cover off today....
Did you know a 0 and 6 look a lot like each other in dusk lighting situations? I do now.

I'll have to detail the roller-coaster day I had in the detailed thread of this project later, but ya that's the short version. Started great this time! Oil pressure was up to where it should have been so that issue definitely got fixed.

And now my battery is dead....
 
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Good to hear.

Sometimes it does pay to read instructions....

Good Luck with Truck!
 
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