Monday morning field repair

[TStark]

Took the Spider to work today, almost there, then Bang! at a stoplight, then sounds like a major exhaust leak from hell but wrong side of engine and engine is shaking, idle dropped.

Inspect, the rearmost spark plug near the firewall riped out of the threads and is laying to the side still ont he plug cable.

I try to make it home to change cars, The thing sounded like it was powered by big briggs and stratton, embarrasing for the breed. half way there traffic is backed up, i get off to bypass the backup, then choose to stop at a parts place

I do an autozone parking lot repair, buy thread repair kit, and penetrating oil, and i have my comprehensive toolkit in the trunk
Stared the engine three different times to blow the shavings out. Not optimal, i understand.

Now my toolkit just got more comprehensive with the plug thread repair kit.

45 minutes i'm on my way to work, the autozone guys seemed oddly impressed. If it wasn't the back plug, i would have been on my way even sooner.

Glad this happed with me in the car!

[cormac]

the same thing happened to me and my '76 on I5 going to Seattle 24 years ago, walked to auto parts store off the closest freeway exit and completed the same repair and was on my way

[Nanonevol]

Did either of you ever find out what would make a spark plug come blasting out of the head?

[azruss]

That last plug hole is easy to cross thread. Once it is cross threaded, you loose 80% of your threads and it is nearly impossible to get it back to the old threads.

[TStark]

Yeah, Like Azruss sez, i think it was compromised long ago by someone in that fashion.

The thread insert went well, sounded more intimidating than it was. I like that the head stays on!

[cormac]

Nanonevol -

I never did figure out why...it was my first couple of weeks with the car...upon purchasing I did an overnight brake job so I could drive to Whidby Island to see a girl

[KevAndAndi]

How does the thread repair kit work, exactly? (In case I ever encounter the same problem.)

[aj81spider]

Here's the thread on how I did my first one:

http://www.fiatspider.com/f08/viewtopic ... ug#p151146

Eventually I did two, one with the engine out of the car (this first one) and one with the engine in the car. The follow up to that is that I could never get the helicoils to seal right. I used several different thread lockers, but couldn't stop getting blow by around the plugs.

I have a new head on order and the old head is removed with the engine waiting to have the new one put on.

[mscafide]

Very impressive TSTARK, I love on the road repairs. It had to be #4.

We need a thread on roadside repairs. I have at least a couple of good stories that I think should be in the archives before I die. As bad as they might have been, I think Fiats look pretty good when they happen.

[TStark]

Oops, looking back seems a few photos of the steps for posterity would have been more thoughtful!

These systems have a two-stage tap that begins as plug threads then chamfers up to the insert's threads. The thing just cut very well and stays true.
Three different insert depths were included, and 'refils' are available.
No drilling was needed.
A dab of RTV on the insert before threading down, then used the plug to screw it in, then could back out the plug and verify depth.
One trick was to first cut the threads all the way deep enough, so the insert can seat far enough so the plugs' metal gasket engages the head.
Only get one chance, in the field, it would be quite problematic to back out the insert so to tap more.

Each time I blew out the chips, I remembered to reprobe the cyllinder to make sure the piston was not close enough for the tap to hit.

The kit resembled this unit, very much like aj81spider used on his. That grease ideas is brilliant, wish I had that foresight
http://shop.advanceautoparts.com/p/heli ... air+kit+14

Being #4 cyl, I needed to go back in to get a 1 3/4" extension. so my ratchet didn't hit the firewall and cause unnecessary misalignment. A wobble drive could have worked in a pinch.

[fillupd]

You can go one step further after the grease on the tap and vacuum of the cylinder. I used a telescoping magnet because the head on it had a big area. I greased it up and dabbed it in my cylinder and on top of my piston. Pulled it out and wiped it off and repeated until no more shavings came up.

If you can get to it easy and have around 160.00 you can get a 'timesert' kit and make a really nice threaded hole. You need to buy the tool to make the sealing surface and it is a little pricey for one spark plug hole.

Don't forget the anti-seize for that plug when reinstalling. Especially that one.

Good story. I agree with above post, a collection of Fiat roadside repair stories would be entertaining, as well, sometimes funny.