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Topic: Spark Plug Change (Read 11 times) previous topic - next topic
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Spark Plug Change
Yahoo Message Number: 89335
I posted a few weeks ago about the blown out spark plug problem that can affect pre-2004 Ford V-10 Triton engines, like many of us have in our E-450 and E-350 LD motorhomes.
I explained what I had learned and what I was going to do to address this potential problem in my 2003 E-450 LD.

To recap what I've learned, a small percentage of these V-10s have been subject to spark plugs being ejected from the heads, sometimes destroying the coil on plug unit for that cylinder.
Some of these have been repaired by replacing the affected head (expensive), others by installing some sort of insert in the damaged plug hole, sometimes with the head off the engine, more often with the head in place (much less expensive).

This problem seems to be most common on pre-2000 chassis, but also occurs occasionally on up into the 2003 model year.
There is no definitive cause of this problem, just a lot of speculation. The one that makes the most sense to me is too few threads in the plug holes and on the spark plugs, apparently only about 4 threads holding these plugs in these aluminum heads on early models.

Motorhome magazine recently published some information implying that in the pre-2000 models some of the heads had defective machining of the plug holes, which certainly wouldn't help. Anyway, the consensus seems to be that the plugs loosen over time and then at some point are ejected.

Ford hasn't shared much information but does seem to have made some changes to address this problem. A revised plug was introduced first, followed by revised heads. The net effect of both changes is plugs with eight threads in heads with eight threads.

And there seems to be a consensus on the Internet that it is advisable to either retorque or change these plugs at about 30K miles instead of the 100K mile plug change interval specified by Ford in our owner's manuals.

There is a company (two bothers actually) operating in two locations in Southern California (Santa Ynez and San Diego) that has done a lot of work to develop a solution to this problem. Their name:

www.blownoutsparkplug.com

The have developed a unique tapered insert system that they can install with the head in place. They will also come to you, anywhere in the country. Their approach is considerably less expensive than new heads. Detailed cost info is on their Web site. I've found no evidence of problems with their approach after doing several hundred repairs.

They also do spark plug changes on these engines, not a simple matter due to the design of these engines and the difficult access to the plugs.

I decided to take a proactive approach to this potential problem by having a plug change done at blownoutsparkplug.com's Santa Ynez location on our way to Baja. I felt this would avoid any surprises by (1) assuring that all plugs were tight and not at risk of blowout and (2) determining which heads I have, old or new. I had the plug change done on February 10.

I was very impressed by the work performed on my E-450.
The work took about two hours but would have taken me most of a weekend. Why? Because they've done this many times before, know exactly what to do and have assembled all the tools for doing this easily and properly. I've never done it and have only a few of the tools, despite having a fairly complete workshop.

They begin by removing the air cleaner and intake ducts down to the throttle body. Then the doghouse inside the cab. They loosen the wiring harnesses for each cylinder bank and remove some hoses. Then they remove the 10 coil units and the boots that attach them to the plugs. Then they blow out the plug holes which can accumulate considerable debris when the boots are removed. Then they remove the plugs, checking the "break loose" torque as they go. Then each plug hole is cleaned with a rotating wire brush to remove any deposits and blown out again. They check the condition of the rubber boots and may recommend new ones (I got new ones even though not really needed). They apply dielectric grease to the tips of the boots and other grease where the boots seal to the heads. New plugs are then installed, the boots and coils are refitted and the other parts that were removed are reinstalled. Then the engine is started and checked for any codes, to verify that all is well.

blownoutsparkplug.com torques the plugs to 28-32 ft/lbs vs. the 15 or so spec'd by Ford. This is a bit controversial but they have had no problems and they believe the root cause of this problem is inadequate torque. They recommend subsequent plug changes at about every 60K miles, but I'd consider doing it more often if I had the 4 thread heads.

I learned that my 2003 V-10 had the new plugs and new heads, eight threads each. That was good news and very reassuring. My research indicated that Ford most likely began using the new heads in November, 2002 but the actual date for any specific vehicle will vary because of varying dates for head manufacture, engine assembly and vehicle assembly.
My vehicle was assembled in May, 2003 and on the end of the driver's side head when the doghouse was removed was a sticker indicating a May, 2003 date for engine assembly.
There is supposedly a date stenciled on the side of the heads indicating their manufacture date, but I can't see that on my motor.

I'd say if you have a 2002 or earlier V-10 you have the old heads and that 2003 was a transition year. The definitive test would be to remove one plug and see how many rotations it takes to screw it back in. About 4 equals old heads. About 8 equals new. The easiest plug to remove would probably be the one nearest the front of the engine on the driver's side, after removing the air cleaner unit.

I also learned that the "break loose" torque for my plugs varied from a high of about 25 ft/lbs to a low of about 5 ft/lbs on one plug. None of the threads in the heads were damaged, but this tells me that , even with my new heads and plugs, one plug was too loose. This means  that it was a good idea to get this work done now and that blownoutsparkplug.com's theory that the problem is too little torque makes sense.

The cost for this work was $400 (which includes the new plugs) plus $100 for the new boots (not really needed but I figured while we were in there, why not replace them to assure a good seal, as I've heard of some problems if water gets past the boots). That's a lot for a spark plug change but not when you see what is involved in doing one on these engines and it compares favorably with what I've heard others were charged at Ford dealers.

And there are a lot of sensitive parts at stake. Each coil unit is about $100 and could be broken in this process and there is a onnector to each coil that you don't want to break. Plus if there is damage to the plug threads noted during a change, then you need to make an insert repair. Given the value of these engines I'd want that done by someone who knows what they're doing and who can do it then, while things are apart. Note that Santa Ynez isn't far from Live Oak Camp, where the LD Caravan Club goes each May and December.

If you have a 2004 or later E-450 I wouldn't worry about this too much. Maybe check the torque. Maybe do the plugs at 60-75K instead of 100K. But for pre-2004 models, and especially pre-2000 models, I'd recommend that you attend to this potential problem in whatever way makes sense to you.
As for me, I'll be returning to blownoutsparkplug.com in about another 60K miles for another plug change.

Terry

2003 26.5' RB

Gardnerville, NV (now in SoCal headed to Baja)
Terry
2003 26.5'RB
Gardnerville, NV

 
Re: Spark Plug Change
Reply #1
Yahoo Message Number: 89353
Terry, while this info doesn't apply to my ancient V-8 E350, I think it was really nice of you to provide this thoughtful, detailed info for others.
Thanks!

Tessa in TX '92 Ciao Baby!