See the quality difference in the Heli-Coil (top) & the Calvan (bottom)
© DenLorsTools.com Summary: In this automotive repair/tool blog we cover Ford spark plugs blown out of cylinder heads, it’s still a huge problem. To date we have sold hundreds of Calvan spark plug thread insert tool kits and have had no one call back to say it was too hard or it didn’t work. The included video makes the spark plug insert repair easy to understand and answers all the questions about how this job can be done in the vehicle saving thousands of dollars. We are commonly asked if the Calvan spark plug repair kit will work after a Heli-Coil or some other thin, weak repair has failed and have blown out AGAIN. The answer is yes, Calvan inserts are much thicker than the competitor’s inserts and will work much like an over-size oil drain plug will work in a stripped out oil pan. Since the Calvan insert is not just a coil of wire like the Heli-Coil it is much stronger. And since the Calvan insert is thicker than the Heli Coil, most times it can be used when the Heli Coil is spit out.
Question: I need to know the size or dimension of the outside of the insert, to know if it will be large enough to repair the spark plug hole threads that have already been fixed once before?
Answer: The outside diameter of the Calvan 389-100 insert is .73″ or 18.65mm, this is measuring on the most outer part of the threads. If a HeliCoil was used before in the original repair this should work well. See the difference in thickness of the inserts (see the image at the top), on the left is the Heli-Coil and on the right is the CalVan 389-100.
Our customers tend to research their options to find the very best solution for this very frustrating problem, that’s why after they research Helicoil we know most will ultimately purchase the Calvan Ford Spark Plug Insert Tool Kit.
Our Automotive Tech Article on Ford spark plug blowouts, goes into much more detail about Ford spark plug problems, including the fact that when buying a rebuilt head the consumer should be aware that it may have an inferior repair insert already installed. That’s why it is our recommendation to repair the cylinder head you have with the Calvan insert tool kit, so you know that you have a strong, long lasting repair that you don’t have to worry about.
Question: How long will the Calvan spark plug repair last?
Answer: The Calvan inserts are designed to last the lifetime of the engine and are stronger than the original threads.
Question:Â Time Sert says “The only 100% way to know the valves are not open is to remove the valve cover and inspect the cam, making sure that it is not depressing the valves on the damaged spark plug hole.” Do I have to remove the valve cover with the Calvan Ford spark plug insert tool kit?
Answer: No. The Calvan tool kit allows the mechanic to verify valves are closed with an included cylinder leak detector. Plug the rubber stopper from the leak detector into the spark plug hole with a low amount of air from an air compressor going through the hose. The rubber cone will pop out of the spark plug hole when the valves are closed. The video shows this as well.
Question: How do I know all the aluminum metal shavings are out of the cylinder?
Answer: A borescope is used to make sure all foreign debris is removed. A video scope can be used as well, we have fairly inexpensive video based scopes that in our opinion, are better and easier to view.
Question: I’m afraid I might start drilling or tapping the hole crooked, am I going to damage my head beyond repair?
Answer: With the Time Sert, the tap has a small pilot at the end of the tap. With the Calvan specialty tool kit (since it is made specifically for Ford 4.6, 5.4 and 6.8 Triton engines) has a guide that fits into the spark plug well to perfectly guide the drill and the tap making the repair centered even in hard to access areas.
Question: Will my spark plug be properly grounded through the engine, since the insert will have JB weld on the threads?
Answer: I’ve only had one person ask this. The answer is yes. JB weld or Loctite with some other brand inserts is being used on the threads, but there is a large enough percentage of metal to metal contact that provides ground, to allow proper firing of the spark plug.
Update 12/01/2011
Time Sert 51459 Inserts in the image below. Notice they are more than just a thin coil of wire.
The Calvan 38900 is for spark plug ports on Ford Triton SOHC 4.6, 5.4 and 6.8 Liter 2 valve engines – 1998-2004. The Time Sert repair kits are made for much more than just the above application. DOHC is not a problem with the Time-Sert 5553. Time Sert makes a kit that will work on most vehicles. This fact has saved our customers a lot of money. Time-Sert’s comprehensive coverage doesn’t stop at “spark plugs”. They make kits for head bolts, main bolts, drain plugs and the list goes on. The Time-Sert inserts are bushing type and NOT just a coil of wire like the Heli Coils are. We have sold tons of the Time Sert kits with no problems reported as well. Still have questions on your application? Feel free to give us a call.
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Related Links and Products
Ford Spark Plug Blow Out Problems How to Repair Original article
Calvan 38900 Insert Kit – Product in this blog for sale
Calvan 389-100 DLT Inserts – Additional inserts sold separately
Expedition Cylinder Head Removal w/Body Off NOT required with the 38900 DLT see what you’re missing
The most common problem we help people deal with is related to parts store thread repair kits that have failed. Once this happens the owner or shop sometimes tries unsuccessfully to re-install another of the same type inserts. When a parts store insert fails it makes the hole bigger, which prevents the same size insert from being able to help matters. Other times, some shops will say (mistakenly) that the cylinder head has to be replaced! If you have a similar situation, we can most likely recommend to you or your repair shop a professional, permanent type repair that will save the head and save a lot of money. No time to read? Call us at 800-524-9783 x251.
The following is an email from a customer: Hello Dennis, Good morning. Hope you’ve had a great summer so far. Quick update for you. I took on the project to install sleeves on all the spark plugs on my V-10 F-250. I had originally installed two sleeves (of lesser quality) and found out that the previous owners had also done another one (of lesser quality also). In all, three spark plugs had blown out of this engine before I decided to replace them all. Â I ordered your 
