Last night we finished up unbolting everything underneath the Jeep and then moved topside.
I have to admit, I tried to use my cordless tools a bit more throughout the beginning of this job, and while many of the fasteners came right out, there were a few that the cordless tools wouldn't even touch. So due to space constraints, out came the IR 90-degree pneumatic impact. I bought this for a specific job several years ago and keep itching to find more uses and last night was one. Zipped the couple of hard to reach and tight fasteners right out.
Once up top, we began removing components from the accessory drive and then focused on wiring. I must admit, the majority of the wire loom is still in pretty decent condition for 20+ years now and 206k miles. There are, however, a few smaller branches that use the plastic split loom convoluted casing that will need some attention when going back together as they crumbled upon removal. For those we will replace with the nylon split loom so everything will look as OE as possible, but with slightly better choice on wire protection against the underhood heat.
Before wasting any more valuable time we wanted to confirm the reluctor wheel tooth count as soon as possible. With the starter motor removed and crank sensor removed we could now sneak a light up in there and verify the reluctor wheel tooth count. This 4.7 liter V8 Chrysler engine was available between 1999 and 2008 and could have either a 16-tooth or a 32-tooth reluctor wheel on the crankshaft.
All of the keyboard experts on the Jeep forums continue to post misinformation regardless of how many people have proven the so called "known determining factors" wrong, they just keep repeating the same mantra regardless.
Most say that between 1999-2002 model years either one is a possibility. But anything manufactured for the 2003 and up model year they will all have a 32-tooth reluctor wheel. Then others will chime in and say there are a few occasions when a 2003 or 2004 can still have a 16-tooth reluctor, although very rare. The "experts" say that the ONLY way to tell is by the VIN or ECM method.
They post that if the 8th digit is an "N" it will have the 32-tooth reluctor wheel and anything other than N as the 8th digit will be a 16-tooth. Another so called "known" or confirmed way of telling is if the ECM has 3 connectors or 4. Supposedly if it has 3 connectors on the ECM then it is a 16-tooth and if it has 4 connectors it has 32 teeth.
Well, when ordering the engine several weeks ago, we kind of took a stab (50/50 chance) because my son's WJ was hit and miss on these "known factors" posted by all of the self-proclaimed experts. Even though a couple of the "tells" leaned towards it having 32-teeth, one stood out to me as indicating 16-teeth. Even the engine rebuilder was not 100% sure and I would think they would know better than anyone. Based on the model year and the VIN# we provided, it leaned towards having 32-teeth, yet his ECM has only 3 connectors for a 16-tooth.
From what we were told by the rebuilder, the 16-tooth is a rarer engine and needed a bit longer lead time so we opted for that with the thinking that if we needed to swap it for the less hard to get engine, we would only be looking at maybe 3-4 days vs. 2-4 weeks for the 32-tooth.
In my opinion, the ONLY way to know what you have and confirm it is to actually count the teeth. The engine we ordered has a 16-tooth reluctor wheel due to the longer lead time so last night with a mirror and paint pen in hand we determined the OEM engine also has a 16-tooth reluctor wheel. Wheeeew. No need to get another engine coming while we waited.
