NEURO
1st Gear Poster
- Joined
- Sep 22, 2023
- Messages
- 43
- Location
- Las Vegas, NV
- Vehicle Details
- 1997 Ford Thunderbird LX Sport with 4.6L V8
Question about the spark plug wire/boot directionality. I posted this on TCCoA a few weeks ago, but no solid answers resulted:
Yeah, I know this is some weapons-grade OCD, but I want this to be right, so bear with me.
A few weeks ago, I replaced the wires, plugs, and ignition coils on my '97 Bird 4.6L. The wires are a new Motorcraft set, but the Ford service manual plug wire drawing/diagram & description confuses me (see photo below):
What directions or o'clock positions should the flat side of the top of the boots point?
It makes a difference because of how it seats & seals the angled plug well. The best I could figure was the following, but I've seen photos/diagrams where the flat sides point rearward or elsewhere:
If looking at the left or right cylinder bank from the respective fender POV:
Spark plug wires = On both banks, flat side should point towards front of engine by a small angle.
Driver-side left bank: Flat side at around 10-11 o'clock position to get the wires to snap on spark plug all the way.
Passenger-side right bank: Flat side at around 1-2 o'clock position to get them to snap on the spark plug all the way.
Is this correct, like I've done in the photos?
More descriptively:
The question is IF I'm correct about those o'clock positionings and if mine are pointing in the right direction in the photos.
They seem to seat properly on the plug at these o'clock positions, seal the plug well opening properly, and look correct visually...but if I follow the service manual's drawing (below), the flat edge sits at a different o'clock position, but also seems to seal the plug well properly. I tried both ways and they both seem to work...but only one way can be right, due to the top lip angles of the boot and the plug well top.
As you can see when you look at the plug boots, the top ridge on each plug boot sits at an angle, relative to the boot top and the two ridges under it and is what seals the plug well when seated properly at the correct o'clock position. In other words, the plug boots can't be installed on the plugs without regard to directionality, like the old days with straight boots; they're directional to ensure the top ridge seals the plug well and seats on the plug properly, since the plug & plug well are at an angle in the heads.
I also have a feeling that this confusion is causing improper seating of the plug boots with other 4.6L owners and is what leads to the common issue of water & debris getting into the plug wells over time. I kid you not...when I replaced my spark plugs & original wires a few weeks ago, they hadn't been touched since 2007; new plugs then, but kept the original wires. Last month, 17 years & 22K miles later, when I replaced the plugs & wires, there was NO debris or liquid in the plug wells when I inspected them visually and then blew them out with my compressor, before removing the plugs, even after a thorough engine cleaning & hose-down. Perhaps they were seated properly, preventing liquid & debris from getting in. Perhaps improper seating is why so many suffer liquid & debris getting into the plug wells over time. Unfortunately, I didn't note the o'clock positioning of the flat edge of the plug boots or take photos before replacing them...so now I'm guessing which way they point.
This page from the Ford service manual isn't clear to me...and the drawings of the plug boots aren't accurate to the real-life plug boots...which prompted my question regarding the o'clock-directionality of the boots.
So what does everyone think?
Thanx
Driver-side bank:
Passenger-side bank:
Pure adults-only 4.6L porn:
Yeah, I know this is some weapons-grade OCD, but I want this to be right, so bear with me.
A few weeks ago, I replaced the wires, plugs, and ignition coils on my '97 Bird 4.6L. The wires are a new Motorcraft set, but the Ford service manual plug wire drawing/diagram & description confuses me (see photo below):
What directions or o'clock positions should the flat side of the top of the boots point?
It makes a difference because of how it seats & seals the angled plug well. The best I could figure was the following, but I've seen photos/diagrams where the flat sides point rearward or elsewhere:
If looking at the left or right cylinder bank from the respective fender POV:
Spark plug wires = On both banks, flat side should point towards front of engine by a small angle.
Driver-side left bank: Flat side at around 10-11 o'clock position to get the wires to snap on spark plug all the way.
Passenger-side right bank: Flat side at around 1-2 o'clock position to get them to snap on the spark plug all the way.
Is this correct, like I've done in the photos?
More descriptively:
The question is IF I'm correct about those o'clock positionings and if mine are pointing in the right direction in the photos.
They seem to seat properly on the plug at these o'clock positions, seal the plug well opening properly, and look correct visually...but if I follow the service manual's drawing (below), the flat edge sits at a different o'clock position, but also seems to seal the plug well properly. I tried both ways and they both seem to work...but only one way can be right, due to the top lip angles of the boot and the plug well top.
As you can see when you look at the plug boots, the top ridge on each plug boot sits at an angle, relative to the boot top and the two ridges under it and is what seals the plug well when seated properly at the correct o'clock position. In other words, the plug boots can't be installed on the plugs without regard to directionality, like the old days with straight boots; they're directional to ensure the top ridge seals the plug well and seats on the plug properly, since the plug & plug well are at an angle in the heads.
I also have a feeling that this confusion is causing improper seating of the plug boots with other 4.6L owners and is what leads to the common issue of water & debris getting into the plug wells over time. I kid you not...when I replaced my spark plugs & original wires a few weeks ago, they hadn't been touched since 2007; new plugs then, but kept the original wires. Last month, 17 years & 22K miles later, when I replaced the plugs & wires, there was NO debris or liquid in the plug wells when I inspected them visually and then blew them out with my compressor, before removing the plugs, even after a thorough engine cleaning & hose-down. Perhaps they were seated properly, preventing liquid & debris from getting in. Perhaps improper seating is why so many suffer liquid & debris getting into the plug wells over time. Unfortunately, I didn't note the o'clock positioning of the flat edge of the plug boots or take photos before replacing them...so now I'm guessing which way they point.
This page from the Ford service manual isn't clear to me...and the drawings of the plug boots aren't accurate to the real-life plug boots...which prompted my question regarding the o'clock-directionality of the boots.
So what does everyone think?
Thanx
Driver-side bank:
Passenger-side bank:
Pure adults-only 4.6L porn:
