Helicoil spark plug repair question - E D I T = Panic Over

[ghost123uk]

Hi all

Well my local T25 friendly garage repaired my damaged (DG WBX) spark plug thread with a Helicoil last week.

All seemed well but for some reason, just as I was doing checks before setting off for a 150 Mile drive on the bank holiday weekend, I decided to check the plug tightness (as a loose plug is what caused the damage in the first place).

3 were OK but the Helicoil repaired one was a bit loose I put a plug socket on it and went to tighten it up but as I was carefully doing so it did not feel right (you know that feeling with threads ?)

I nipped it up as tight as I dared (considerably less torque than you would normally use on a plug) and set off hoping for the best. It got me there and back, but on checking it a few times on the journey you could still feel a very slight wobble to the plug (not good I know). It was not unscrewing or getting any worse so I left "sleeping dogs lie" as I did not want to risk attempting to tighten it up, stripping it and getting stranded.

I will go back to the garage and ask their advice, but was hoping someone on here could offer some words so I know what I am talking about when I go to speak to them.

By the way, because they owed my a favour, the Garage did not charge me for the helicoil job, tho the motive for that now has me a bit worried, did they know the job had not gone 100% right ? ).

Was wondering what to do to fix it ?
What would you do, take the plug out and have a look to see if the helicoil looks good ?
Tighten it up properly and hope it torques down correctly (as I said, it felt funny when I went to tighten it)
Use some high temperature threadlok on it (I have some)

Can a faulty helicoil job be "re-done" in any way ?

Sorry for the long post - just a tad concerned about the possible consequences of all this .

[paul66beetle]

Helicoils suck! I especially wouldn't want to use one on a head either!!!! You run the risk of bits falling in the head and causing more damage IMHO.

[ghost123uk]

You run the risk of bits falling in the head and causing more damage IMHO.

Fortunately there was a thread on here recently that I used as a reference re this and the garage were aware of the problem and the cure (Grease and taking 5 or 6 goes at the thread cutting)

Helicoils suck! I especially wouldn't want to use one on a head either!!!!

Bit late now - you got anything useful to add ? (he asked respectfully, as in, I don't mean to sound rude !)

[paul66beetle]

I suppose you are limited in your choices.

As you can tell I am not a fan of helicoils, but what are the alternatives? A replacement head £££

If it still feels loose then I wouldn't be confident in the helicoil. If done properly it should feel nice and tight.

[A KIRK]

There isn't rally any other option for repairing other than a helicoil. Helicoils can be good provinding there done right and at the correct angle etc. I guess the problem comes witha head is the amount of heat created and the two different metals heat up and cool at different rates.

You might also find when removing the plug that the helicoil comes out with it which is a complete pain I know this frm experience as I had a head recked due to helicoils which in the end cracked the head.

Personally I'd leave it it for now if its working and not causing any real issues, but I think the only real way of repairing it 100% would be for a new head which we all know is a lot of money.

[lloyd]

Time-Sert is better system. Here's a thread:
viewtopic.php?f=2&t=64677&p=7460118&hilit=timesert#p7460118

[ghost123uk]

Thanks for that Lloyd

I will see what the garage has to say and report back.

I wonder if anyone around the N.W. does these Time-Sert jobs ?

[Little Miss Pink]

Well my local T25 friendly garage repaired my damaged (DG WBX) spark plug thread with a Helicoil last week

I thought Steve was the T25 wiz in your area, who do you use? doesn't sound good with a wobbly bit in there

[steve8090]

Not guilty Sara

[ghost123uk]

No Sarah it was not Steve.

Anyway panic over.

The guy at the garage took the plug out and had a look with a little magnifying mirror and a torch, (and showed me too) and the helicoil is in place, in good nick etc.

It was me being too timid with the spanner (being worried about stripping it and the consequences of that !)
He got the torque wrench out and tightened it to the correct setting as I watched with no worries.

Then he undid it again and let me torque it down so I would be confident it "felt right" and was OK.

Whewww

[HarryMann]

Can a faulty helicoil job be "re-done" in any way ?

Yes, should b able to remove and refit, with the right tool

Helicoils not crap by the way, whoever said that, they've been used for years, in the aviation industry as well (sometimes specified as new) and done properly are stronger than the original (of course, because they spread the load wider than the original thread).

Anyway, you're home and dry now and it should stay put