Motorcraft Platinum spark plugs after 132,000 miles

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762mm

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Well, I just finished one of the top two "urgent" maintenance items on my SSV : rebuilt the original alternator and installed 8 new Champion Iridium 9406 (which I gapped to the 0.054 spec)

I pulled the Motorcraft Platinums out of the Triton, which I assume were the originals. The plugs came out fairly easy, however the rear ones were a PITA, especially the one on the passenger side. I had to apply so much torque on the ratchet I was afraid I'd break something with that one... The new plugs went in with some anti-seize on them and were tightened by hand till they went in no more, then about 1/4 turn with the ratchet extra to make them snug.

I measured the gap on the old plugs and, strangely enough, they had inconsistent wear. Some plugs were 0.060 or a little more, whereas the worst one was in the 0.075 territory! :boxed:


If you do this, here's an important tip: when you remove each boot, before putting the socket in there, blow the spark plug channel out with compressed air (using a long wand air gun). Then, once you start removing the spark plug about half way, stop, pull out the socket and blow it out again to get the debris that was squeezed under the plug out. The amount of debris, sand and even pebbles that came out of there was astounding!

Also, do them one at a time, so you do not contaminate the neighboring plug channels when you blow out the debris, because it literally flies everywhere.


Anyway, here are some pictures:

Spark-Plugs-1.jpg


Old vs. new :

Spark-Plugs-2.jpg


Original 8 plugs comparison :

Spark-Plugs-3.jpg



Here's the tutorial I used :

 
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TobyU

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I see a lot of electrode wear all the time. I often see them at .068-.072.
I always gap at a tight .052 since I know they are going to erode away some.

Always inspect the boots very well and if they are too swelled up at the bottoms it is a good idea to change them out.
 

TobyU

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I see a lot of electrode wear all the time. I often see them at .068-.072.
I always gap at a tight .052 since I know they are going to erode away some.

Always inspect the boots very well and if they are too swelled up at the bottoms it is a good idea to change them out.
 
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762mm

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The boots were in good shape. I blew them out a bit with compressed air inside and I did use dielectric grease upon reinstall, of course.

I was thinking of changing the coils anyway (my MPG is only 12.4 for some reason), but am keeping the old ones for now...
 

99WhiteC5Coupe

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GM (yes I know, not Ford) has issued a TSB instructing technicians not to adjust the gap on spark plugs with iridium tips, as the adjustment can cause damage to the iridium coating. The bulletin states to check the gap, and if not within specs, to discard or return the plug.

Here is some good information regarding anti seize compound on spark plugs: http://www.jagrepair.com/images/AutoRepairPhotos/NGK_TB-0630111antisieze.pdf
 
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762mm

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GM (yes I know, not Ford) has issued a TSB instructing technicians not to adjust the gap on spark plugs with iridium tips, as the adjustment can cause damage to the iridium coating. The bulletin states to check the gap, and if not within specs, to discard or return the plug.

Here is some good information regarding anti seize compound on spark plugs: http://www.jagrepair.com/images/AutoRepairPhotos/NGK_TB-0630111antisieze.pdf


The initial gap on these plugs was 0.041 and other iridium brands (NGK) at 0.044, so I had no choice but to adjust it. There was no Motorcraft version available. I made sure not to mess with the electrode though (which is the iridium component) and visually inspected each plug afterwards. I've driven the truck today on a mix of city / highway and it actually feels like it runs better. The engine is quieter too, it seems.

Good info on the anti-seize, I was already aware of it. I made sure not to tighten them like a 600 pound gorilla, only until it was "snug" to the feel (my torque wrench is busted and can't be trusted). The old #4 plug was so damn tight in the engine that I was actually worried it would snap upon removal (no anti-seize)... but it didn't. I guess they are tougher than they look, lol.

I was working on a cold engine by the way, which probably made removal of old plugs tougher. I've heard that working on a warm or hot engine can damage the head threads, though... and to go at it when it's cold.
 
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TobyU

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The initial gap on these plugs was 0.041 and other iridium brands (NGK) at 0.044, so I had no choice but to adjust it. There was no Motorcraft version available. I made sure not to mess with the electrode though (which is the iridium component) and visually inspected each plug afterwards. I've driven the truck today on a mix of city / highway and it actually feels like it runs better. The engine is quieter too, it seems.

Good info on the anti-seize, I was already aware of it. I made sure not to tighten them like a 600 pound gorilla, only until it was "snug" to the feel (my torque wrench is busted and can't be trusted). The old #4 plug was so damn tight in the engine that I was actually worried it would snap upon removal (no anti-seize)... but it didn't. I guess they are tougher than they look, lol.

I was working on a cold engine by the way, which probably made removal of old plugs tougher. I've heard that working on a warm or hot engine can damage the head threads, though... and to go at it when it's cold.
Their point is you risk more of a chance doing damage by adjusting on the special tip design than not. .003 is insignificant to the plug gap in the situation.
I don't think you'll ever catch me installing iridium plugs on an engine unless the customer just flat-out insist. There's really no point in paying that much for a spark plug. I put single platinum's on my own and occasionally at the price is right I might have had some double platinum's but a single platinum plug last me many many years and many many miles so there's no reason to pay anymore. I usually get the single platinums for 269-to 3.69 I plug. You can even get better deals you order them online but I would just assume to buy them locally since they're so cheap anyways.
I could care less what original equipment is and half of these parts stores will try to sell you a radians and tell them that's OEM for a car built in like 2000. What a scam.
 
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762mm

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I paid the equivalent of $4 USD per plug at Rockauto. Local parts stores will rape you on any plugs, even if you pay shop prices.

Iridium plugs are in the $15-20 range up here. Hence why Rockauto is my to go place for 90% of parts on all our family cars / trucks.

Besides, iridium electrodes just don't burn. That's why some manufacturers are now using them as "lifetime" plugs, especially on sideways mounted engines with difficult access to the rear bank (like Lexus / Toyota). If I don't have to do them again in the next 10+ years, I'll be a happy guy and will gladly pay the extra $10 for all 8 plugs!

;)
 
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