The Dreaded Spark Plug ejection!

[mrv8outboard]

Originally Posted by Waiter21

mrv8outboard;

Is that the kit that Mark linked to in post #12 ???

No, they are different. The inserts are thin and are flared at the top of the insert rather than the bottom like the Time-Sert. The Time-Sert will repair the hole where that type and other are blown out of as well.

[mrt_1111]

Who personally had a ford v10 blow a spark plug and what did you do to fix it?

[mrt_1111]

Nobody?

[n2587n]

I see it a lot , I own a truck and car repair shop. It is common ,

[ga traveler]

Originally Posted by mrt_1111

Who personally had a ford v10 blow a spark plug and what did you do to fix it?

Did you read my opening statement ? The weird thing is, I researched the problem and it is usually the number 4 plug. Mine was the number 4 plug. After finding out it is almost always the number four plug, I have decided to redo the installation (remove the plug that I locktited in and install a insert.) and change all plugs.

[Darryl]

Can this be prevented by doing anything before it blows out?

[nothermark]

Originally Posted by Darryl

Can this be prevented by doing anything before it blows out?

It's not guaranteed to happen.

If changing plugs follow Ford's recommended procedure. Most failures reportedly can be traced back to poor installation practices.

[Darryl]

Originally Posted by nothermark

It's not guaranteed to happen.

If changing plugs follow Ford's recommended procedure. Most failures reportedly can be traced back to poor installation practices.

I've got around 42K on my 1998. I'm guessing they are original. Do you think it would be worth while to take it to a Ford dealer and get them changed?

[mrt_1111]

Originally Posted by ga traveler

Did you read my opening statement ? The weird thing is, I researched the problem and it is usually the number 4 plug. Mine was the number 4 plug. After finding out it is almost always the number four plug, I have decided to redo the installation (remove the plug that I locktited in and install a insert.) and change all plugs.

Do you happen to have a bore scope that will take pictures number 4? I be interested in knowing how many threads are in there.

[nothermark]

Originally Posted by Darryl

I've got around 42K on my 1998. I'm guessing they are original. Do you think it would be worth while to take it to a Ford dealer and get them changed?

The plugs are platinum rated for 100,000 miles. Early problems were in the transportation sector where non believer mechanics decided to change them much earlier and usually without a torque wrench. They often ended up pulling the heads to fix or replace them hence "the problem". By the time the RV industry caught up the various fixit kits were developed. If you are really worried buy a kit and keep it in the MH. In the mean time take a large wrench to any mechanic who wants to mess with the plugs. You may never need to change them if you have 42K on a 1998. This is a case where being proactive is a bad idea.

[mrv8outboard]

I have done many in my shop. Seen all cylinders do it. I also have some that have never had an issue with the spark plugs. Why some and not all?

So to sort of answer that you first have to understand that engineers made it to work under factory conditions. This does not always work in the real world.

There is always a cause for the consequence.

Scenario one, loose or improperly tightened spark plugs at change of the plugs.

Scenario two, Detonation, this coupled with the lack of thread count leads to the ejection of the spark plug. Think of it like an air impact gun or air hammer. It will loosen the plug enough to compromise the thread integrity and pow, out come the plug.

The second is the most common I find and it also explains why is it not all but some.

Fuel quality is the worst contributor. Oil quality and cooling system maintenance. Load and general maintenance follow.

Then there is some with all prevention measures utilized it still fails.

[ga traveler]

Originally Posted by mrt_1111

Do you happen to have a bore scope that will take pictures number 4? I be interested in knowing how many threads are in there.

I don't have a bore scope,but I don't need one. I checked the plug when it came out. It had 1 aluminum thread on the plug. It was obvious the plug had worked it self loose and was hanging by one thread. I used red locktite and installed a new plug and coil. (did nothing to the threads.)It got us home from Daytona with no problem. I am going to install a new insert because I am afraid 3 threads are not enough and the threads might be worn from the loose plug. I am also going to have the new plugs torqued to 28 ft lbs. That is almost twice as tight as Ford called for. I have never heard of a plug ejection on a V10 with plugs torqued at 28 ft. lbs. There is a company in California that does V10 ejection repairs and will guarantee no blown plugs that they torque to 28 ft pounds.

[ga traveler]

Originally Posted by Darryl

I've got around 42K on my 1998. I'm guessing they are original. Do you think it would be worth while to take it to a Ford dealer and get them changed?

Most V10 engines never have a problem. Mine is also a 1998. If you do decide to change plugs. Don't go back with the original Platinum plug. Go to the iridium plug and have them torqued to 28 ft lbs. If you do this you are good for almost 200,000 miles on your coach. The V10 with iridium plugs are rated for 100,000 miles, but many people are going over 150,000 miles with no problems.

[Waiter21]

I've got around 42K on my 1998. I'm guessing they are original. Do you think it would be worth while to take it to a Ford dealer and get them changed?

I just turned 60k miles on my 1999. I'm going to leave them until 100k miles, That should be 4-5 years...