Hello all,
I just wanted to know some info on my 99 f250 V10. I will be replacing plugs shortly and would like to know the torque specs for 1999 V10s. Is the correct procedure to put antiseeze on the threads and torque to 11 ft/lb or 132 in/lbs, or were the specs different in 99? Also, what percent of these engines actually blow plugs? Im curious to see what the odds are of a V10 to blow a plug. On this site, you hear about it a lot b/c its a "trouble-shooting site." However, they made millions of these engines...just curious. Thanks in advance.

Nate

 

I torqued the ones in my '01 to 14 ft/lbs. I'm pretty sure I read that in my service manual CD, besides Fredvon's postings.

Unless someone else speaks up, put them at what the factory service manual says for your year. If there is any truth to "less threads in the head before 2000-01", 11 ft/lbs might be all that they can stand.

Fred? Any opinions on this?

 

First the "dreaded plug blow out" is NOT a common or frequent problem. It is very dramatic and can be real expensive to repair. I am convince that for the percent of trucks that are under torqued at the factory or by an incompetent owner or technician the problem is 100% preventable. Unfortunately aluminum is NOT forgiving at all and if a plug was EVER OVER TORQUED then eventually that hole WILL FAIL and there is not a thing that can be done to prevent it.

I recommend that any person that owns a Ford modular motor with aluminum heads check or have a competent technician check the plugs for perfect installation and a check re-torque every 30,000-50,000 miles for the life of the motor.

I have never seen the specs for pre 2000 V10s but all the books and web searches I ever did had 14 foot lbs (Dry) or 168inch Lbs (Dry).

There is an excellent post here on this page for all the tools and items needed to do the job correctly.

More on the DRY issue. All of us here recommend that a VERY LITTLE coating of anti seize be used on the THREADS and CONTACT ridge to prevent steel to aluminum GALLING. This compound will act sort of like a lubricant. We acept that risk because we need the contact of the steel to aluminum to not create corrosion caused by the electroloysis of dissimalar metals...anti seize compound can slow down the corrosion. With out it the weak aluminum threads can bond to the plug's steel threads and tear or shear off during removal. The aluminum threads have such a close interferance fit that they can also GALL as the plug is INSTALLED or REMOVED and this makes the torque reading false too early and removes some of the aluminum thread material making them weaker.

My method of installation ignores this (lubrication factor) fact and I torque in TWO stages. Once all plugs are in finger tight, I torque them all first to 10Foot lbs (120 inch lbs) Remember that the motor must be completely cool to ambient (outside) air temperature. That means between 65 and 90 degrees Fahrenheit. (A few degrees either side is OK but if it is 1008F out or 45F and lower outside I would not do this procedure unless you know the torque compensation factor). Then I start with the same sequence and final torque to 14 Foot lbs (168 inch pounds). This method allows a little time for the semi lubricated threads to relax and equalize befor the final torque. I learned this technique for an old guy at the drag strip skooling me on why my Harley heads kept blowing plugs across the pit!

I looked it up in one of our engineering books one time and just had to guess at the aluminum type of the Ford heads. For that thread pitch and diameter you can safely go to around 16 foot lbs (190-194 inch lbs) and each of the three aluminum tempers were within a few inch lbs of the same spec so I think as long as you do not go above the 14FTlbs that Ford recommends you should be safe 95% of the time. (the lubrication of the threads will cause further turning into the bore for the same torque vs. dry torque witch would have more interference drag.

By very LITTLE anti seize. I usually mean just barely any on the threads and contact surface. This is NOT a case where MORE is Better!

 

My manual for the 2001 model said 11 ft lb. 15 Newton Meter

The 1999 may be different.

Ford does not recommend that you put ant-seize on the threads.

The Motorcraft application book says that anti-sieze is not required. If you do put it then you should reduce the torque so the plug is not overtorqued. The motorcraft application book specifies a higher torque then the manual.

I went ahead and applied a small ammount of anti-seize and torqued to 11 ft lb. / 132 in lb.

The new plugs are plated with nickel. This is to reduce the chances of rust.

http://www.fordinstallersupport.com/...logs/spark.pdf

This is the motorcraft application manual.

On page 67

FORD TRUCK - — Cont’d
10 Cylinder — Cont’d
2001
6.8L (S) ............................... AGSF22WMF4 422WM .054
2000-98
6.8L (S) ............................... AGSF22WMF4 422WM .054
1997
6.8L (S) ............................... AGSF22FSMF4 4114 .044


On page 10

Torque Information
Use shown values only when threads on spark
plugs are clean, dry and smooth, the plug has
been finger tightened and a new folded gasket
used (except in the case of tapered seats). The
use of thread lubricants is not recommended but
if lubricant is used, torque values should be
reduced to avoid possibility of over torquing.
* For 14mm and 18mm tapered seat – if no
torque wrench available – tighten 1/16 turn (snug)
after finger tight.

ALUMINUM HEADS

PLUG THREAD Ft Lb Newton Meter
14mm Tapered Seat 7-15 9-20



The plugs listed in the owners manual and service manual are no longer avaliable. They have been replaced by AGSF22WM. I think the same is true for the 1999 year model.

Make sure you replace the boots. The part number is FMC F7TZ 12A402 AA.

They list for $11.90 each. I asked for a discount and got them for 9.64 each. That is still way too high. The ford dealer gave me the wrong plugs so I purchaced the replacments at O-Reily auto parts. They were about 1.2 the price of the dealership. $2.29 vs $4.75

The two most importent things to remember.

Clean out the holes, inspect them and then clean them again. Use high pressure air.

Use a good torque wrench. I used a 250 in lb wrench. The required 132 in lb torque spec is in the middle of the range where it is the most accurate.

Do not over torque. You do not have many threads.

132 in lb = 11 ft lb = 11 ft lb x 12 inches.

https://www.ford-trucks.com/forums/s...d.php?t=458496

This is a link to my thread showing pictures and a step by step procedure.

 

Thanks for the responses,
I need some more advice. I have had the plugs changed about 20,000 miles ago by my local mechanic who did not torque them down. Should I replace the plugs, then antiseeze (a small amt.) and torque them down or can I just go through with a torque wrench, torque them to spec, and hold off on antiseeze and boots for another 30,000 miles? Also, thanks again for the wealth of information. Take care and God Bless.

Nate

 

I'll probably get some flack for this but I'll say it anyway

I'm a tech at a Ford dealer and I don't think I've ever seen any mechanic anywhere actually torque a spark plug. Most of us have a pretty good feel for how tight things should be but I also think that overtightening fasteners is very common.
Of all the plugs I've seen blow out I don't recall ever seeing one that had been recently replaced blow out. Usually they are original plugs. You can tell an original plug by the pain dab on the end where it goes into the wire or COP boot.
Right or wrong, I was told by a Ford engineer not to use anti-seize on the spark plug threads. Some people do, some people don't.
It's best to have the engine cool before replacing spark plugs but realistically it very rarely happens. In a shop where someone is paying to have work done you can't afford to have the vehicle sit and cool down so a spark plug can be replaced. It doesn't cause any problems that I've seen.
If anyone ever questions you on whether or not Motorcraft plugs are good, today I worked on a Windstar that had a bit of a rough idle. I scanned it and got a P0174 lean code and also a pending P0305 misfire code. The P0305 was just pending which means that it hadn't occurred often enough to turn on the check engine light or to set a code. I pulled out #5 spark plug to take a look. It was the original and was definately due to be replaced. Then I looked at the odometer.........266,000 kms!
Not a bad ignition system

 

Well I did not torque spark plugs for years.

I did not own a torque wrench. My first Engine overhaul prompted me to purchase a good torque wrench. After that I used it as much as possible. Most of the time you did not have room to torque all the plugs. There was always one or two that you could not get to. Never had a problem.

Then I started working on boat motors with Al heads. That made a believer out of me. I stripped out a couple of spark plug holes and from then on I started using a torque wrench. BOAT MOTOR HEADS ARE CHEAP COMPARED TO V10 HEADS.

7 to 15 ft lb is the spec. I am sure a Mechanic that works on engines all day long has enough feel to get pretty close. 7 to 15 ft lb is a pretty small range. I am sure that I would probably over torque the plugs. I probably would not strip the threads but why take the chance. The Anti-Sieze is probably not required and may even be a mistake. I am parinoid about al threads galling so I decided it is worth the risk.

I AGREE MAKE SURE THE ENGINE IS ROOM TEMP. YOU ARE A LOT LESS LIKELY TO DAMAGE THE THREADS. AL IS SOFT AND HAS A LARGE EXPANSION RATIO. IF THE ENGINE IS HOT IT IS SOFTER THAN IF IT IS COLD. ALSO IT GRIPPS THE PLUG TIGHTER DUE TO EXPANSION.

Would I use a torque wrench on a cast iron motor. Yes on the plugs I can get to. It would not worry me if I had to torque one or two by hand. With Al heads I would remove whatever was necessary to get to the plugs with the torque wrench.

That is not a problem on the 6.8L. There is plenty of room to torque the plugs. The main reasion I changed my own plugs is that I was worried about the dealer mechanic stripping out the holes and sticking me with a $3000 bill.

 

I have a question for Studentut65. Why are you changing the plugs?

Ford rates them for 100,000 miles. I changed mine at 106,000 miles. The plugs looked good. Just starting to erode. The boots were cracked and in my estimation is more of a problem than the plugs. One of the plugs had a water mark where water leaked past the boot and filled one of the holes. I purchased the truck after the initial break in of 80,000 miles so I have no idea what happened. I noticed that the number 9 plug had a rust line and all the Cop's on that side had anti-sieze on the screws. I assume that the PO flooded it out and pulled the COP's to dry out the plugs.

The Truck runs exactly the same after the plug change as before. Perfect.

I can see changing them in a salt enviornment. I would be worried about them rusting. The new plugs are plated which helps with that problem.

I was talking to one of my retired friends and mentioned about the dirt collecting in the spark plug hole. He said that they had exactly the same problem with the Model A's. Water would fill the holes and short the plugs and they would fill up with dirt. You had to clean them before changing plugs.

I guess what comes arround goes arround.

 

I don't know about you, but every time I've changed the plugs in my '96/'97 4.6L's, and my V10, it's run better afterwards. And that's with as little as 20K miles between changes. And, they were usually more-than-slightly worn even at that mileage. The change always gave just a touch more throttle response than before.

Cleaning and re-gapping them also was noticable (in the4.6), but not worth the effort for the cost of the plugs.

 

Hello all,
Again, thanks for more comments. I had the plugs changed at 95,000 miles. I now have 115,000 miles on it and am finally getting a chance to torque the plugs down. I just was thinking that it would be better to replace and install new plugs correctly (torque, antiseeze, etc). But now, I think I will just go over the plugs with a torque wrench this weekend since I have the time. I really dont want to spent over 130 bucks to change plugs that only have 20,000 miles on them. Thanks guys for the comments.

Nate

 

Is that $130 doing it yourself? Those are some EXPENSIVE plugs

 

If a plug hole in the head only has 4 threads, then why in the world would you install a plug with 8 or 10 threads on it....????

But, I guess Ford knows what they're doing...

I have a '99 and used the anti-seize, di-electric grease, 14 lb tq method about 57K miles ago. Getting ready to do it again.

 

Why make two plugs when one will do.

More threads does not make any differance and they only have one plug to make and stock. I wonder why they made the plug with few threads in the first place.

I wonder why they put so few threads in the head. I would thought more is better with no differance in the cost.

If you puchase the plugs from an auto house they should cost less than $3.00 each. The boots are $10 from Ford but you only need to change them every $100,000 miles or five years. Mine were still servicable They were just starting to crack where they plugged on the spark plug.

After market boots are avaliable for less than $4 but I decided to stay with Ford parts. If I felt the need to change the plugs every $20,000 miles I would inspect the boots and only replace them if they are cracked.

I paid $130 for plugs and boots.

Purchasing everything from the dealer would of been $155.

If you are getting 100,000 miles from the plugs that is cheap.

 

Wanna doe-see-doe?
I don't know, but I would imagine that the thread length was determined by the plug-hole threads in the head..

Now....
Because they had already purchased the boots at a certain length?

I really don't know, but screwing 4 to 6 threads down into a firing chamber, where they are exposed, don't actually sound like a "fix" worth a coon's tooth to me...

 

Just purchased plugs and boots from a FTE sponsor ( discount ford parts ) that cost about $120...which included the shipping. I agree...going with a local dealer would have cost me $155-$165 for the same items.

This is a GREAT thread! Glad it was posted...

biz