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  #1  
Old 07-23-2011, 08:10 PM
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#5 Spark Plug Ejected

Good news: I finally figured out what that valvetrain-like ticking noise coming from the engine was.

Bad news: It was the #5 spark plug getting ready to come out. It happened on the way home from the store today as I was cresting the last hill. I heard a loud pop and briefly got some smoke in the cabin. The smoke quickly went away and I heard what I thought was a bad exhaust leak. Upon returning home I investigated and found that the #5 cylinder had an empty hole where the spark plug should have been. I located the plug, still attached to its wire. It's still screwed into an insert of some sort which was blown out with the plug. The insert has ridges on it which I thought were threads, but aren't.

How do I fix this?

Edit: Just to clarify, this is on the 114.011 with the M130 engine. My Kawasaki only has two spark plugs, and my other vehicle thankfully has none.

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Last edited by Skippy; 07-23-2011 at 08:27 PM.
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  #2  
Old 07-24-2011, 05:58 AM
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What's the condition of the hole in the head like - I'm not wishing more disaster - I mean the bit where the insert goes... could you "just" get a replacement insert and screw it back in?
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  #3  
Old 07-24-2011, 07:40 AM
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Is the offending cylinder the only one that has this insert (some some of helicoil) or do they all have them?
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  #4  
Old 07-24-2011, 01:53 PM
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a helicoil is often used if a spark plug hole has been mis threaded and ruined. Unfortunately you will have to have that redone or have the head removed and hole rethreaded. In most cases that is not a great option because you then have one spark plug that is "odd man out" ( different size or adapted) depending on access - the helicoil , done correctly, will serve a long time. If the access is not such that the tools can be used to place the coil , you may be looking at pulling head
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  #5  
Old 07-24-2011, 08:55 PM
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After letting the engine cool, I re-examined everything. The insert thing is in fact threaded and I was able to screw it partly back into the hole by hand. Unfortunately, my 13/16 spark plug socket is at work, so I won't be wrenching on my car until Tuesday at the earliest (class on Mon and Wed until late). I also couldn't pull any of the other spark plugs to see if they have inserts or are threaded directly into the head.

I also took the liberty of contacting Pick N Pull for a quote, and I talked to a guy I know last night who wants to buy the car and fix it up for his wife. Of course, he was pretty drunk, so we'll see if he still wants the car when he's sober.
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83 300D Turbo with manual conversion, early W126 vented front rotors and H4 headlights 400,xxx miles
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88 Jaguar XJS V12 94,xxx miles. Work in progress.
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  #6  
Old 07-24-2011, 09:31 PM
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a helicoil put in properly should not work itself free, any chance to take a picture, I feel certian your other plugs will not have the same set up unless some previous owner decided to port the heads for some reason
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16 F350 6.7 Diesel -THOR
19 BMW X5 - Heaven on Wheels
14 38HP John Deere 3038E Tractor -Mean Green
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  #7  
Old 07-24-2011, 09:55 PM
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Unfortunately I'm enough of a Luddite/cheapskate that I don't have a digital camera. I'm pretty sure the object isn't a helicoil. It's a little more substantial than that.
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Whoever said there's nothing more expensive than a cheap Mercedes never had a cheap Jaguar.

83 300D Turbo with manual conversion, early W126 vented front rotors and H4 headlights 400,xxx miles
08 Suzuki GSX-R600 M4 Slip-on 22,xxx miles
88 Jaguar XJS V12 94,xxx miles. Work in progress.
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  #8  
Old 07-25-2011, 01:20 AM
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A proper spark plug helicoil (as opposed to a bolt one) is heat-treated and solid versus "Wound spring" looking.
http://i108.photobucket.com/albums/n31/thehumble1/KZ440/KZ440_save-a-thread015_small.jpg

It is unlikely that it will remain in if it came out once already. If the helicoil/insert was not put in properly the new threads it used are likely shot. You can try, using some red (permanent) loctite.
http://www.amazon.com/Threadlocker-High-Strength-bottle-37479/dp/B0002KKTQS/ref=sr_1_2?ie=UTF8&qid=1311571182&sr=8-2
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  #9  
Old 07-25-2011, 04:22 PM
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Quote:
Originally Posted by Tomguy View Post
A proper spark plug helicoil (as opposed to a bolt one) is heat-treated and solid versus "Wound spring" looking.
http://i108.photobucket.com/albums/n31/thehumble1/KZ440/KZ440_save-a-thread015_small.jpg
Yup. That's what it looks like.

Quote:
It is unlikely that it will remain in if it came out once already. If the helicoil/insert was not put in properly the new threads it used are likely shot. You can try, using some red (permanent) loctite.
http://www.amazon.com/Threadlocker-High-Strength-bottle-37479/dp/B0002KKTQS/ref=sr_1_2?ie=UTF8&qid=1311571182&sr=8-2
Only the last two threads are deformed. I might try the loctite when I screw it back in.

I've just about exhausted my patience for this carbureted spark ignited slush bucket POS. If it's not a quick fix, I'm dropping the price to whatever PNP is offering.
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Whoever said there's nothing more expensive than a cheap Mercedes never had a cheap Jaguar.

83 300D Turbo with manual conversion, early W126 vented front rotors and H4 headlights 400,xxx miles
08 Suzuki GSX-R600 M4 Slip-on 22,xxx miles
88 Jaguar XJS V12 94,xxx miles. Work in progress.
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  #10  
Old 07-25-2011, 08:39 PM
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that is also what I was referring to, and unlikely it will stay put even with locktight, will need a new one, with re threaded hole
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2015 Porsche Cayman - Elizabeth
2011 Porsche Cayman - Bond,James Bond
Sadly MERCEDESLESS - ALways LOOKING !
99 E320 THE Queen Mary - SOLD
62 220b - Dolly - Finally my Finny! Sadly SOLD
72 450SL, Pearl-SOLD
16 F350 6.7 Diesel -THOR
19 BMW X5 - Heaven on Wheels
14 38HP John Deere 3038E Tractor -Mean Green
84 300SD, Benjamin -SOLD
71 220 - W115-Libby ( my first love) -SOLD
73 280 - W114 "Organspende" Rest in Peace
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  #11  
Old 07-26-2011, 12:24 PM
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I've read interesting claims that "forged aluminum" inserts are MUCH better than steel ones because of differences in coefficient of expansion.

I have a spare head that I can get repaired at a shop, and with the head off, I think they can do things with it that are impossible to do with the head on the engine.
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  #12  
Old 07-26-2011, 01:46 PM
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taking the head off is the way to do this repair so that all threading and fittment is done under inspection, I suspect this one may have failed because of the access to the plug hole, speculation, but most likely. I have seen this repair last many many years and tons of miles when done correctly.
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2015 Porsche Cayman - Elizabeth
2011 Porsche Cayman - Bond,James Bond
Sadly MERCEDESLESS - ALways LOOKING !
99 E320 THE Queen Mary - SOLD
62 220b - Dolly - Finally my Finny! Sadly SOLD
72 450SL, Pearl-SOLD
16 F350 6.7 Diesel -THOR
19 BMW X5 - Heaven on Wheels
14 38HP John Deere 3038E Tractor -Mean Green
84 300SD, Benjamin -SOLD
71 220 - W115-Libby ( my first love) -SOLD
73 280 - W114 "Organspende" Rest in Peace
81 380 SL - Rest in Peace
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  #13  
Old 07-26-2011, 11:08 PM
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A couple of suggestions

You mentioned that you thought that only a couple of threads were messed up, but you don't cite on which part. I assume that the 'messed up' threads are on the cyl head. Is this correct?

If so, then can you thread the plug with it's thread insert on it into the hole without cross-treading it?

If the answer to this is YES, then you may be able to make it work without removing the cyl head.

If you can thread it in, then you can evaluate by feel the sizing of the pitch diameter (PD) of the thread insert sized internal thread in the plug hole. If the PD's of the internal & external thread get too much allowance (gap), then you will feel a lot of wiggle when the two threads are engaged but not locked down. This is the aspect to evaluate if you can get that insert, on the plug, threaded into the hole.

If the wiggle is not too bad, then I think you could make a reliable joint by threading the cleaned insert into the hole with some JB Weld on the threads. I know this may sound rather drastic, but if you're at the point of taking off the head or getting rid of the car, then it would seem an option worth considering.

It's viability is hinged on you being able to get the insert threaded in and not have a lot of wiggle in the fit.

If your evaluation meets these criteria and you decide to do it, then I would suggest removing the insert from the plug and cleaning it well with Brakekleen, alcohol or some non-greasy solvent. Then put a little anti-sieze on the plug external threads. Then thread the cleaned insert on to the plug threads IN/OUT and look to make sure you've got a good anti-sieze coverage while still making sure you've kept the insert external threads clean and snug the insert onto the plug as best as possible with pliers & a plug wrench or spanner. Then tooth-brush clean the plug hole with alcohol or the like.

Carefully apply a little JB Weld to the entrance of the plug hole and try to get some coverage around the full circle.

Apply the JB Weld to the external threads on the insert on the plug, but don't go all the way to the leading edge, but stay back 1-2 threads. This will keep the JB weld from getting in front of the threads. Use a brush gently to get even coverage on the rest of the threads behind those lead threads.

Thread the insert in on the plug with maybe a little back & forth like using a cutting tap; in a couple turns, back a quarter turn, in another couple of turns, back a quarter, etc.

Once you get to the bottom, be very gentle in tightening. Use a plug socket feeling the torque very carefully; you don't want the aluminum to yield. Even about 5 ft-lb torque would be acceptable as the JB Weld will greatly enhance the load bearing capacity of the threaded joint where the allowance in the fit of the PD's is excessive.

Let the JB Weld cure overnight, remove the plug, inspect everything, re-thread the plug in with anti-sieze to ~15 ft-lbs and see if it holds.

I think it might be a viable option.
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  #14  
Old 07-26-2011, 11:23 PM
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I went to the parts store today and bought a helicoil. It was way thinner than the thing that popped out with the spark plug. I showed the original to the guys at NAPA and they'd never seen one. They suggested a local shop which isn't convenient for me. I might try the parts manager where I work. As an experiment, I threaded the old insert into the old hole. It made it in about two threads worth and still had a little wiggle after I ran the engine for 30-60 seconds. It didn't completely seal the cylinder. I don't like the car enough to pull the head, in fact I've been trying to get rid of it for some time. I checked with PNP to see what they'd pay, and while I was pleasantly surprised with the answer, I decided to try craigslist one more time for a little more money.

The JB Weld thing is worth considering (I had actually thought of it and dismissed it), but I don't know how long it would last. I JB Welded a cracked exhaust manifold once, and got a little short of 500 miles out of it. BTW, the speedometer cable broke about a week before this, adding to the list of things I'd need to fix in order to keep this car as my winter beater.
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Whoever said there's nothing more expensive than a cheap Mercedes never had a cheap Jaguar.

83 300D Turbo with manual conversion, early W126 vented front rotors and H4 headlights 400,xxx miles
08 Suzuki GSX-R600 M4 Slip-on 22,xxx miles
88 Jaguar XJS V12 94,xxx miles. Work in progress.
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  #15  
Old 07-27-2011, 04:56 PM
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I agree, although an option , the area has toi be spotless of grease, the heat in the area I believe would eventually lead to the JB weld demise

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2015 Porsche Cayman - Elizabeth
2011 Porsche Cayman - Bond,James Bond
Sadly MERCEDESLESS - ALways LOOKING !
99 E320 THE Queen Mary - SOLD
62 220b - Dolly - Finally my Finny! Sadly SOLD
72 450SL, Pearl-SOLD
16 F350 6.7 Diesel -THOR
19 BMW X5 - Heaven on Wheels
14 38HP John Deere 3038E Tractor -Mean Green
84 300SD, Benjamin -SOLD
71 220 - W115-Libby ( my first love) -SOLD
73 280 - W114 "Organspende" Rest in Peace
81 380 SL - Rest in Peace
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