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Discussion Starter #1
She told me it had been 'shifting funny' for a few weeks. I initially thought TC or transmission issues as it ran fine when I'd drive it.

Then she told me it was 'smoking' really bad in the morning.

It finally tripped a P0308 and I was happy thinking I'd just replace the crappy plugs and buy a new coil pack for #8.

Initial driving after the change she said everything was good. About two weeks later and there is quite a bit of smoke and today it threw code P0300.

I've been thinking head gasket after pulling #8 and seeing it look darker, then hearing about the smoke, then seeing the white smoke, and trying to rev in neutral, it hits a wall at 4,000 RPM with a bad miss.

The morning is the worst obviously when a hot/pressurized system forces coolant through a blown gasket after parking it.

I haven't tackled a head gasket since I did the top of a 96 Tahoe 5.7 and am not looking forward to it but it beats paying thousands to have it done at a shop.

I've looked for the pointers and things specific to the 4.7...doesn't sound fun. Hope to start tearing it down during the nights next week since she's done with school for a few weeks after this Friday.
 

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Discussion Starter #3
Engine is torn apart, dropped the heads off at the machine shop today. I managed to break one of the secondary plastic chain guides as well as the plastic piece on the primary chain guide. I've been going back and forth trying to make a few decisions before I get the heads back and started bolting things back together.

- Should I buy an entire timing chain kit considering the age and miles or just the two plastic guides that I bought? If I buy an entire kit, is there any difference in the kits that sell for ~$150 on Amazon vs the kits that sell for $300?

- At close to 120,000 miles, what else should I be doing? The water pump was replaced around 90,000. I was told not to worry about the fan clutch but I did buy both idler/belt pulleys.

- Not intending to open up a topic that has been discussed in depth, but I thought about doing the HO cams while I have everything apart. The machine shop advised that the valves are different on the HO heads and my understanding is that I'd need to run the HO's fuel injectors as well as tune the ECM to gain much in addition to the intake/exhaust. In the end, the cost seems to add up quickly compared to the gains. I think I will possibly just add a tuner to get a little out of it. Diablo or something like that. Thoughts?

- We bought a 2004 Lincoln Aviator to drive as a second vehicle with 135,000. WOW...that motor is amazing!
 

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If your depending on the vehicle for reliable daily transportation, I say keep it all stock. Like you said, picking and choosing from some of the HO parts will likely make for worse performance/reliability, you've got to install the whole package. Not to mention, just the cams, don't be surprised if fail emissions inspection, if you have to get tested in your state.

Timing Chains should last the life of the vehicle, that is NOT break, they will stretch and effect engine performance, but its just a matter if they have stretched enough already. That you should have accessed before you pulled them off, if they didn't have any slack in them before pulling them off, I'd keep the OEM chains and put them back on. (I don't have any experience with timing chains on the newer motors, if someone with more experience offers an opinion, I'd listen to them.)

Bear in mind, in many cases replacement parts are inferior quality compared to the OEM parts, so a replacement chain may stretch more than the OEM chain is currently stretched in very short time.
 

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Discussion Starter #5
I'm thinking I will replace all of the tensioners/guides but the chains seemed great to me and I planned to install them unless I heard different.

I am also considering a radiator replacement to prevent any issues should the 8 year old rad have issues in another 20-50k miles.
 

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Actually, what does the FSM say?

It may say to replace the chains anytime they are pulled, I really doubt it.

They may have some sort of measurement or test to tell if the chains are good to be put back into service.

They may just say to visually check before pulling them, if they look fine and NOT stretched, to go ahead and re-use them.

Radiator? I know the plastic cap radiators never last the life of the vehicle anymore, but again, you're running into the decision of throwing away a good OEM part and replacing it with a new inferior quality part. If you're positive the replacement radiator is as high quality as the OEM part (meaning its NOT the cheapest offering from the corner auto store) maybe you'd avoid a leaking radiator at 10 years of life. Don't be shocked if the OEM radiator would probably still be leak free 3 years from now, while a cheap replacement radiator would be leaking at only 3 years old.
 

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Discussion Starter #7
Agree at the radiator thoughts. This head gasket job was such a PITA I found myself trying to think of every little thing to prevent ever needing to do it again. While the head leak began without an overheat, I told her if the engine ever gets hot, shut it off and never limp it somewhere. Same reason I thought about replacing the fan clutch. The other side of the coin is that I hate throwing money away.

Manual doesn't recommend replacing chains, just inspecting and checking tolerance. Again, it got me thinking "what if" and in searching for the guides, I'm finding whole kits as opposed to just the I individual pieces I need.
 

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Discussion Starter #8
Everything is back together for the most part. I need help on one thing though and didn't take any pictures pulling it apart. On the inside of the passenger side fender on the engine bay, the electrical that is mounted to the side has a ground wire...where is the other end grounded? Does it go to the back of the cylinder head on the passenger side? There is another ground wire there but I don't remember taking both of them off when I disassembled it. That being said, there isn't much else that needs to be bolted up yet. It could reach the alternator or AC compressor bolts but I don't remember it going there either.

...help?
 
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