Spark plug thread repair

[gabriel]

So my kit came with thread inserts (solid type not wire wound), a thread cutting tool, and a punching tool.

I’ve cut the threads already but am unsure how to put the insert in the proper way.

Would I screw the insert on to a plug and then coat the exterior threads of the insert with rtv silicone? Then I just screw this assembly into the hole? By hand or with wrench? After I unscrew plug and use the punching tool? How do I make sure the insert doesn’t come back out with the plug?

Thanks

[Casey Lynn]

None here are mind readers. We do not know if it is a "fix a thread" kit, a time sert, or another brand.
The more information you provide the better the answers you will recieive.
At any rate, figure out which one you have and google it! Usually a YouTube video will pop up.
None are difficult to do.

[dan-in-tn]

Whatever you do Im pretty sure RTV won’t be your sealant of choice. Not what I would use.

Dan in TN

[Mumbles]

f you are using the Heli Coil brand spark plug thread repair kit, READ THE INSTRUCTIONS on the back of the package. It says red Hi-Temp silicone must be used to help seal the insert. Staking it in with the special tool locks the insert into the head so it can’t come out.

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[chris-p]

You can use a plug to thread it in, or just use the tip of your finger. As stated, they recommend using red high temp on the exterior threads. If you use a plug to insert in, oil the internal threads, so that comes out easier and doesn’t back the insert out with it. I add the high temp to the external threads of insert, oil to internal, lock in with old spark plug. Let dry overnight. Back plug out in morning, then use the punching tool to lock it down.

[dan-in-tn]

I went on their site to read about these inserts. I am glad to see that they are using inserts! Much better than Heli-Coils which is the brand name. Spiraling threads. I hate those things, just my opinion. They talk about their use in Triton (Ford) aluminum heads. Those spark plugs don’t use gasket type plugs. (Just something to remember). Not sure if that will cause a sealing problem, but I did notice the under cut at the top of the insert? They are also a steel insert. When we did a marine insert we always used stainless steel,for obvious reason. The top of the insert is in square with the head surface. The insert is put in with Loctite HT 400 . I can’t imagine why they would use a silicone based adhesive. (They don’t mention any adhesive on the site). We have never had an insert leak! Iguess part of this could be for the DIY application. It is hard to do professional insert installation. We were usually putting in inserts after removing broken bolts. If they couldn’t be removed successfully the the hole was enlarged and an insert was installed. Just a few more things to consider.
I don’t like inserts on spark plugs because plugs are removed often. If another head can be had I would go that way. Just my opinion!

Dan in TN

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