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Ford Spark Plug Blow Out Problems How to Repair

Ford Spark Plug Blow Out Problems How to RepairSummary: Ford spark plug blowout repair is covered in this article for the Triton 4.6, 5.4 & 6.8 liter SOHC (Single Over Head) engines. Don't have a Ford? No problem, for a wider coverage of spark plug thread repairs see our Time-Sert Kits. Don't have time to read to figure out which kit is best for your application? We can help. Please let us know what you're working on using our contact us form or give us a call, we'll be glad to help. 

There are different brand insert repairs available for this Ford spark plug problem, however they are not all as effective and long lasting as the solution we recommend. Many Ford dealers quote thousands of dollars to replace the cylinder heads, when our spark plug thread repair can be done in the vehicle over the fender for a fraction of the cost. We sell some competitive brands like Lisle and Helicoil, however the Horizon made Calvan 38900 (Mount.9200 same w/different labeling) is the best repair system on the market today using a steel alloy insert that shares similar properties with aluminum, but is much stronger! Update - 2013 Time-Sert now has the largest outside diameter kit available that can be used when previous repairs have made the hole so large that the Calvan 38900 cannot work. See the Largest Ford Spark Plug Thread Repair Article on our sister site for more information.

We've sold hundreds of these spark plug thread repair kits, saving Ford owners a lot of time and money in the process. In the following article we'll explain why this should be the next and last "over the fender" repair (even in vans) purchased for this particular application. Be sure to visit the FAQ tool blog which is recommended reading if doing the job for the first time and finally the Calvan 38900 product page when ready to purchase. Note that 2004 and up 3V engines use a different kit - Calvan 39300 or Time-Sert 3221 DLT. The Calvan 38900 DLT is for Triton engines from 1998-2004, if working on a DOHC InTech engine, use Time-Sert 5553 (Wise Auto Tools). If working on a 2004 and up 3V engine with M16x1.5 spark plugs use the Calvan 39300 or the TIME-SERT 3221.

Ford spark plugs blowing out is a common problem with Triton engines in Ford F150 pick up trucks, Mustangs, Crown Victorias, Vans, Expeditions and motor homes made before 2004. A video showing spark repair inserts being installed can be viewed on the Calvan specialty tool description page. Read on for more information.

Ford 4.6, 5.4 and 6.8 modular engines are prone to spark plugs being blown out of the cylinders due to the aluminum threads failing. When the threads are about to come loose there is often a slight ticking sound/noise, like a small "exhaust manifold leak" would sound.

When the spark plug threads fail, it can eject the spark plug and break the ignition coil on the "coil over spark plug" design. Although rare, it is possible an engine compartment fire can erupt due to the raw fuel escaping the engine cylinder and the broken coil dangling, providing the spark. The cause of failure of the spark plug threads can be debated; poor design, over-torquing, under-tightening can allow the spark plug to vibrate and wear threads while held in by the coil, until the threads deteriorate and eventually fail. We have some Ford dealers that use our kit, however most Ford dealers will not recommend repairing the threads. Many only recommend replacing the cylinder head. The expense involved, unless the vehicle is still under an aftermarket warranty can run into thousands of dollars.

Below is another reason we recommend using the over the fender repair as opposed to removing the heads.

Gaining access to the cylinder head bolts is difficult on trucks and SUV's to remove and re-torque the heads, most Ford technicians do a "cab off" or "body off" operation. On trucks the cab is unbolted from the frame, on SUV's and vans the entire body is unbolted from the frame, the electrical wiring, AC lines, radiator hoses, heater hoses, master cylinder, etc. are disconnected allowing the tech to use the car lift to raise the cab or body off of the frame. Once this is done the engine can be serviced much easier. This process takes less time than you might expect after the tech has done a few of these and knows exactly what needs to be done. However, using our kit and eliminating the need to do all that extra work is advisable.
Below explains the difference between HeliCoil and the Calvan type insert

Many techs at car repair shops will use a Heli-coil repair kit to install a new Heli-coil insert. Techs are familiar with HeliCoils that are good for many applications. The name HeliCoil is kind genric name that we refer to thread inserts. Sort of how many people refer to a Kleenex but really mean it as a generic term for facial tissue. Just to clarify though; THe Calvan type insert is NOT the same as the Heli Coil. The Calvan one is thicker and much stronger and will not leak compression. They also last the life of the vehicle. That being said, I actually have used the Heli-coil repair kit on two different occasions (years before selling tools) and neither of them failed that I am aware of. One concern of using the Heli-coil is that combustion pressure may escape the cylinder since the spark plug may not seat perfectly. I am also aware of a very experienced tech (also an ASE Master Tech) I used to work with that installed a Heli-coil. However it did fail within a week after it's installation. The cylinder head was removed and sent to the machine shop, subsequently it was deemed as "not repairable" by the machine shop. If we would have only known about the Calvan 38900 repair kit back then, the cylinder could have been saved. This is because the Calvan insert is much thicker (.73" O.D.) and is large enough to repair a spark plug hole that has had a Helicoil fail previously. In fact, we commonly sell to customers that have had a Heli-Coil repair fail and blow back out. We also have had many customer's that have tried cheap parts store kits that only bought them a little time before they were back in the same situation. A Blown spark plug. 

DenLors has sold the Calvan 38900 (and Mount9200 same kit) since 2005. We continually sell around 3-5 thousand dollars worth of these kits every month since then. And we've had no reported failures! The spark plug thread repair inserts are installed over the fender without the need to remove the cylinder head.

Using the Calvan 38900 DLT Specialty Tool Kit
It's worth saying again "the Calvan kit has a much thicker insert that can be used when other thinner repairs like the Heli-coil has failed to hold". Using the kit requires about the same access as if you were changing the spark plugs. Just a few steps more. The instruction video provides details on using the kit, but there are more tips that we have collected over the years that we have been selling this kit. These tips are emailed to our customers upon purchase. We will also personally answer questions if needed, but we've found the tips clarify the job.

At checkout just write "Tips" in the Comments field and we will email the tips when processing the order.

Additional Tips

1. Emailed free after purchase.

2. Emailed free after purchase.

3. Emailed free after purchase.

4. Emailed free after purchase.

Horizon Tools makes the Calvan Kit, also sold as Mount9200 and other labels including Blue Point (sold by Snappy for about twice the price). Gotta say the guys at Horizon Tools have really done their homework. One of our customers has a Ford speed shop and when they are beefing up any 4.6 or 5.4 engine, all eight cylinders gets a new Calvan insert to prevent the possibility of any future spark plug blow-outs.

Basic Tool List

1. Standard Pliers (not included) 5/8" Spark Plug Socket (not included)
2. 3/8" Drive Extensions (not included)
3. Inspection Scope (not included) - about 10% of our customers purchase one.
4. Air Ratchet (not included) If a good quality air ratchet is not on hand we can ship one at the same time.
5. Starter Button-optional (not included) Manually turning the engine with a socket and ratchet on the crank bolt eliminates the need for a starter button. 
6. Cylinder Leak Detector (included in 38900 kit)
7. Air Blow Gun with 8" of Small Tubing (not included)
8. Safety Glasses (not included)
Lubrication like PB Blaster or WD40 (not included)
9. JB Weld (not included)
10. 3/8" Ratchet (not included)
11. Shop Towels (not included)
12. Air Compressor (not included)

Below are a few of the questions we have answered relate to spark plug blow outs in Ford and Lincoln vehicles. See our mechanics FAQ tool blog for even more questions answered on this topic.

Question: I have a 1999 Ford F150 with a 4.6 liter Triton engine with 126,000 miles on it. The number 3 spark plug blew out of the cylinder head. I called my local repair shop and was told that this was a common problem with this design engine because of the extremely thin (aluminum) casting in the spark plug area of the engine head, there is only about five threads for a spark plug. How is the Calvan insert better?

Answer: While it is true there is only five threads for the spark plug in this design engine for the spark plug and the Calvan insert has five spark plug threads as well, the Calvan spark plug insert is steel not aluminum and the insert itself is held in place with ten external threads. The Calvan spark plug insert improves the design and durability at fraction of the cost of replacing the cylinder heads with the same design weakness.

Question: I am selling my truck as fast as I can get a spark plug to stay in long enough to get rid of it. I wanted to use a Heli-coil because I won't have to drill, but the thread tool isn't long enough to reach in the spark plug recess, any suggestions?

Answer: I personally recommend the Calvan tool because it is a better repair, but if you would rather use the thinner Heli-coil insert, the HEL5396-14 has the longer thread tool than the standard Heli-coil kit.

Question: I have Ford van that has had a TimeSert installed previously, it has blown out and I want to know if the Calvan insert will work since the Time Sert has left a bigger hole now?

Answer: Yes, the Calvan spark plug repair insert is a larger insert and has worked well for our customers before, saving the expense of replacing the heads. See our auto repair/tool blogfor more information.

Question: I bought a rebuilt head and come to find out one spark plug holes had a repair insert, it blew out last week. The cylinder head has a warranty, but I cannot afford the down time all over again. Will the Calvan insert repair this hole?

Answer: Yes, the Calvan insert is a thicker beefier repair that you don't have to worry about. And I always tell our customers that when purchasing a rebuilt head of this type to be aware of the possibility that inferior repair inserts may be in the head. Buying a brand new head would insure that there are no cheap inserts, but you would be stuck with the original weak design. The Calvan thread insert repair saves down time, money and is stronger due to the material being steel alloy instead of aluminum like the original threads.

Related Repair Articles and Specialty Tools

Calvan 38900 Ford Spark Plug Insert Kit - for Triton SOHC 1998-2004 with M14x1.25 Taper Seat Plugs

Blowout FAQ's Recommended Reading for Using CAL38900 - Your question may be answered in this blog. We've compiled a ton of questions we've had on this job since 2005.

Expedition Cylinder Head Removal – Body Off - *Removing the body is NOT required for use of the 38900 DLT thread repair kit. Just see what you're missing!

Video Inspection Cameras - To help verify metal shavings are removed after drilling tapping etc.

Air Ratchets - A good quality air ratchet is recommended by Calvan for drilling, using the bit in the 38900 kit.

TIME-SERT 5553 - Ford Spark Plug Repair Kit - PN 5553 for DOHC InTech engines and many other Ford applications when used with the proper insert.

TIME-SERT 3221 - for most 2004-2008 3 Valve engines with 16x1.5mm threads.

Calvan 39300 - also for most 2004-2008 3 Valve engines with 16x1.5mm threads.

Below Covers 04 & up Different Ford Spark Plug Problems - 3V Broken Spark Plugs & Porcelain Staying In

Question: I have an 05 Ford F150 with a 5.4 liter engine that has a spark plug broken and I can't remove the broken piece because the part that the spark plug socket goes on came out. I know this is a completely different problem than threads missing, but do you know how I can remove the broken spark plug without removing the head?

Answer: You are right this is a totally different issue, but you're not alone. What we used to sell for this problem was a spark plug remover, a specialty tool made by Rotunda, the number is 303-1203. We use to sell a lot of the 303-1203 special service kits, but now the LIS 65600 is what we sell the most of for removing Ford broken spark plugs. See the LIS 65600 DLT in use tool blog for more information.

Question: I'm looking for Ford Rotunda OTC tool number 303-1398 for removing the ceramic or porcelain part of the spark plug. Thanks, David

Answer: The Rotunda 303-1398 and 303-1203 are pictured above, they are expensive Rotunda specialty tools. Calvan has low cost alternatives and the tool number are CAL39100 & CAL39200. THe porcelain extractor tool kit has pins that are loc-tited into the center of the broken porcelain and only can be used once. The the electrode remover can be used.

There is another method though, instead of gluing "one use" pins, a tool manufacturer has a different solution, The LIS65600 DLT broken spark plug remover mentioned before can be used as an alternative option to the 303-1398 & the 303-1203. The Lisle 65600 Ford spark plug remover, is designed to push the ceramic part of the plug further down, but not into the cylinder. Then, the same tool kit removes the electrode shield. This automotive specialty tool kit is used in place of the two Rotunda tools (303-1203 and the 303-1398) at only a fraction of the cost. A special thanks to Bill at ProCare Automotive for being the first to try this tool out and report back to us, since then this is the tool we have passed this information along. He said the LIS 65600 worked perfectly and was happy to know this tool can be used on more than one vehicle, unlike the 303-1398. Since that first sale of the LIS65600, we've sold hundreds with positive feedback! We've also posted a blog that has pictures of the LIS 65600 DLT in use. Be sure to check it out and you'll have a better idea of how this tool works. Click the following to go directly to the Lisle 65600 DLT product listing. 

Update 2013 - See the Rotunda Type Tool and watch the video on the following product listing (on our sister site) for my Ford Spark Plug Tool Review after selling these tools for several years now - Safest Ford Spark Plug Removal Tool.

Linking: Please reference this article when quoting, linking to this page is welcomed and appreciated. If you are new to linking a page. 1. Left click the URL to highlight 2. Right click, select copy 3. Right click and paste to forum, blog web page etc. Thanks! Disclaimer: Repair tips are designed for informational purposes only, without warranty of any kind, in no event shall the author of this site be liable for any consequential, incidental or direct damages sustained in the course of using the information in this article.
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