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Zetec 2.0 Spark Plug Popping Out

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12K views 12 replies 6 participants last post by  amc49  
#1 ·
So today I was driving and one of my spark plugs came out of the head. Car was running fine before hand. I didn't have a wrench on me so I had it towed home. Put the plug back in and drove it a few miles. Ran fine till the plug came out again.

The first time The gap was totally closed. I opened it back up before I re installed. When it popped out the second time the gap was closed again. It doesn't look hammered though. I haven't tried to put it back in yet. The threads were still in the head after it came out the first time. I hope they're still there now.

I haven't taken one of these engines apart. What could cause something like this?? Did I just not tighten the plug?? Even then, the gap being closed, something must be hitting it.
 
#2 ·
Let's think on that again, you don't think it's possible the end of the plug hit something AFTER it came out?

Not tightened OR over tightened are the two reasons for one to come out.

First possibility you can have a few damaged threads in the head, second they're ALL damaged.
 
#3 · (Edited)
The gap could have closed while the plug was bouncing around, I guess. I don't think it had been over tightened. I just do a little more than finger tighten. It's been a while since I changed the plugs. Like probably over a year. There was no aluminum on the plug. I think the head is stripped now though. :( I stuck a claw grabber thing in the cylinder and didn't feel anything in there. It was running fine. No knocking or anything.
 
#4 ·
Try a flashlight, needed to see the threads down in the hole.

Plugs need to be tightened 'snug' by hand, but with the tapered seat type used that also means that they turn VERY little when tightening once the seat contacts. Older types with gaskets could make a quarter turn to tight as a new gasket crushed.
 
#5 · (Edited)
Hi L200B,

This happened to me 2 years ago I documented the fix here:

Index of /focus-2001-zetec-head-removal

It involves a number of expensive specialty tools but it is doable in your driveway. Cost is a few hundred in parts not including the fee the machine shop is going to charge. This IS an advanced engine repair job so DO NOT attempt it unless you have the time and patience to do it right. The head MUST come off because it has to be mounted in a jig to do the repair and it MUST be skin milled before going back on the engine. The block mating surface has to be completely cleaned before putting everything back.

With this engine IMHO the factory made a mistake and cut some of the plugs in too deeply on some of the heads. As a result the last thread of the plug sticks out into the cylinder a bit too far. Then over time that thread end gets carboned up and if someone removes the plug later, there is enough carbon on the end of the plug to damage the threads on the way out. This weakens them enough that high cylinder pressures will blow the plug out. In my case I was doing 110Mph for an hour on the I-5 Interstate Highway with an average RPM of around 5k when it happened. (No, I'm not saying what stretch that was. ;-)

My understanding is people that race these helicoil ALL the plug holes.

You can see this in the picture I put up of the head, the number 1 plug is definitely deeper in than the others, and on my head that's the one that blew out.

Here is my recommend procedure in dealing with these Zetecs on plug changes:

1) ALWAYS use the Motorcraft platinum plugs and DO NOT regularly change them. Once every 50k miles is fine. That should work out to no more than 4-5 plug changes over the life of the engine.

2) NEVER change plugs on a warm head. Only remove plugs when the engine has sat stone cold overnight.

3) When pulling the plug follow this procedure:

a) Loosen the plug 1 turn
b) Squirt a lot of PB Blaster into the plug hole surrounding the plug.
c) Give it several hours to penetrate down the threads.
d) REMOVE BY HAND if you have to use leverage on a ratchet when removing the plugs, something is wrong.

Good luck with it!

PS Sorry the pictures up there stink, I lost half of them when the phone I was taking them with crapped out
 
#7 ·
So I just drove it for the first time really. The check engine light is on. Which I guess I would expect after losing a cylinder. I'm going to reset it before I drive it again. It had full power. I was worried it was going to miss because the plug wouldn't have a good ground. Not an issue. I didn't let it get super hot this time. JB Weld is rated for 500
F degrees constant, 600 degrees F intermittent. That sounds relatively safe to me. I will have to drive it more to be sure.

A few days ago I bought a Chevy Tahoe. Already feeling the pain. Not as fun to drive. MUCH worse MPG. I want to be able to tow though. About the only thing I don't think the Escape can handle.

This truck was rear ended not too long ago. Cosmetic damage for the most part. If that weren't the case I'd be in a bigger hurry to swap the head. I see rebuilt heads for these for like 200 bucks online. Eventually I'll get around to swapping it out. Or maybe just buy another Escape. Great vehicle. Super fun to drive. Good MPG.
 
#9 ·
OK L200B,

Can we get an update on the JB Weld repair?

Did it hold up?

I ask because at 180K miles my 2009 zetec 2.0 has popped out a plug, I tried the heli-coil repair but the head was so messed up that the heli-coil has nothing to hold on. I am considering JB Weld on the heli-coil to see if it will would it in.

Expecting only 250K on this motor, I figure if I have to remove the head at this point then I probably should just get a Reman'd motor for a swap, or overhaul this motor COMPLETELY if I have to do this.

Thoughts??
 
#8 ·
Well, good luck to you on that - I don't know of anyone who has successfully kept a plug in a head for any length of time using JB Weld - but I also don't know anyone who has tried it and had it fail and admitted it, either. Please post a followup if it works for 50k miles or if it fails sooner than that. At the worst, if it fails it will not have damaged the hole further.

Unfortunately with the Zetecs there's really no possible way to repair a plug thread without pulling the head. The hole is too deep in the head.

I've see a lot of criticism over the years on using helicoils for plug repair but the one in my Zetec's head has been there for around 30k miles now. And most critics of them seem to be Timesert distributors so they are biased anyway. I still maintain the effectiveness of a heli-coil for plug repair is directly affected by the experience and skill of the mechanic putting it in, which might account for why so many people criticize them - because it's easy to criticize something you don't have the skill to properly do.
 
#13 · (Edited)
'...that the JB weld stories mostly never work.'

X2. Because like with so many other things, the issue is not the product, it is the implementation that fails the job. So many do not grasp that.

Beyond that, that post sounds scarily like one of my own. Do you have a more irascible cloned brother?

Man, I heard so many glue fix stories when I used to sell JB that I knew the majority of them were fake, and you could see the obvious need to work dripping off the desperate in a flood, they believed more than they did in the Messiah. Great product used correctly but the human brain behind it must be correct too.