Heli coil or taper for spark plug

Morning everyone, question.

I need to helicoil my spark plug insert, yesterday morning my spark plug blew its insert out and damage ingnition coil. My friend wants to taper it. I would like to know with the help of you guys, do I remove the head or try to do it as is. I think I spelled it right helicoil?

95 Toyota Tacoma 3.4l 4x4 SR5

 

Take my advice, theres many insert options out there & none work as good as "time-sert"
But you need to be very mechanically incline or you can make matters worse...
Theres YouTube videos & videos on time-serts website...

DO NOT use a heli coil for that, whatever you do.....
heli coils are not for sparkplug thread repairs.
DO NOT use one of the many cheaper sparkplug insert options, ive seen many blow out, come out with the sparkplug, etc....

Ive done 1000's of sparkplug time-serts on many fords, the 4.6L, 5.4L 6.8L for blown out spark plugs......


Or find a competent shop with the tools & kit, & have them do it.....

 

You also need valve cover gaskets & sparkplugwell seals....

 

I had this happen on my 3.4L as well. The first shop I took it to put an insert in and it failed when I tried to remove the Spark plug just to see how things looked. I took it to another shop and he did a better job. But I sold the truck like six months later so I can’t speak to the longevity. Wish I knew which mechanics used what. How’s that for help lol. Good luck!

 

Thank you slater and ZTWatson, I will look I to the videos and see what mechanics are able to do this job locally. Appreciate the help.

 

I had this happen on my 3.4 in December of last year. Plug didn't blow out but I was getting exhaust blowing up past the plug threads and out the top of the VC. I bought a spark plug repair kit for pretty cheap at autozone and tapped the new threads myself, without removing the head. It came with inserts a few different lengths, and the tap. It's been 6 months and ~6k miles with no issues, we'll see how long it holds up. Did it the cheap & fast way because I needed the truck back on the road for work ASAP.

If you want to go this route, grease up the tap generously to catch as much of the aluminum shavings as possible. You are still almost guaranteed to get shavings in the cylinder, so make sure the piston is close to TDC, close enough you can see the piston surface when you shine a light down the plug hole. Once you tap the threads, fish some thin tubing down into the plug hole and attached it to a vacuum or shop vac to suck up any shavings in the cylinder. Make sure to use high temp thread locker on the outside of the insert and let it set overnight.

@slater is probably right, he's done it 1,000 times and I've done it once, just telling you what I did in this situation, definitely not saying it's the best or smartest move

Here was my thread: https://www.tacomaworld.com/threads/clacking-sound-from-cylinder-4-1999-2wd-3-4l.847859/

Ediit: this was the kit i picked up, or something very similar https://www.autozone.com/test-scan-...aAgcHEALw_wcB&gclsrc=aw.ds&new_store_set=true

 

Keenserts are what I know from aerospace. I've done Helicoil "repairs" in the past, they don't last very long if you're constantly removing spark bolts.





It isn't the best idea to do these on your own stuff as a 1st time installer, the oversized hole and tap needed are cost prohibitive. Call around to any local automotive machine shops, maybe they could do this in the paring lot for you.

 

From my experience, The time seat kit really locks the insert in & theyre not coming out...
We've had our tune techs come to me so many time in the past where theyre performing spark plugs swaps & the cheap inserts come out with the sparkplug.

Then youre screwed inregards try to source the correct insert, you have no idea what tool kit was used so no idea what threads were cut in the head....
Cant just grab any kit & start over, its not a universal one size fits all scenario...

Looks like the auto zone kit just has 1 installation tool, one does it all.
time sert,
has a cutting tool,
a counter sinking cutting tool,
a tap to cut threads in head for insert,
then another tool to install & expend / lock in the insert.

 

Not picking on you but from your description sounds like you went fiddle fucking & when you removed the plug to have a look, the insert came with it?

 

I use Time Sert's...

 

Slater, I see your in San Diego. I’m in north county, Pauma valley. Any recommendations for a shop in SD? Or your shop if possible?

 

Thats an issue, wish I had the answer....
Ide love to know of a San Diego toyota engine guru....
I have zero resources that I would trust even though I do know a handful of local independent guys, cant say I trust them....

This whole toyota deal is new to me....
I didnt want a big f150 & everything that came through my stall was bad so kind of hard to sleep at night with a $60k f-1 time bomb sitting in my driveway...
Toyota may not be any better at this point but I dont know what I dont know....

Love the tacoma but the paint is quite the joke, stuff is so soft & thin.....sadly comical...
Took me by surprise,
I always knew ford paint was better than toyota paint but not to this extent.
Im not even talking about the visual blemishes we've been dealing with...

I was a master engine tech / line tech for 32 years for ford dealership in La Mesa...
Worked at the some place my entire career.
Was family owned since 1920 "Drew Ford" until about almost 10 years ago, when Penske bought the franchise but land was never sold....
Then few years ago after Penske put their spin / remodel on the property, they flipped it to Sedano.
I retired in 2023.
Line work at dealer level consisted of anything engine related & manual trans, along with overheat concerns, coolant, oil, exhaust leaks / work, vibrations, noises, broken bolts regardless who broke them,

 

Inregards to a shop that would do the insert....
Are theyre any engine rebuilders, machine shops, in your area?
Thats where I would start calling, alot of them are time-sert users...

I know Action Cylinder Heads in Santee uses time-serts & do sparkplug hole repairs but thats a distance for you...

 

Hah fair enough. I think I was worried that the single electrode spark plugs in there were potentially a problem so I swapped them out and then when I got to that cylinder it came out.

 

As I stated, not picking on you, if it was a quality seat & done correctly, its shouldn't have come out....

 

Yeah I agree it shouldn’t have come out. The shop did a shit job or missed a step. Not the first time I’ve unscrewed something.

 

Probably didnt miss a step, the cheap ones are just that, they suck,,,,