1997 Honda Civic Ejected spark plug

Tiny
MALMADAM
  • MEMBER
  • 1997 HONDA CIVIC
  • 4 CYL
  • FWD
  • MANUAL
  • 15,000 MILES
While driving on the highway under not much load ( flat land ) in 5th gear, my honda hatchback all the sudden launched/ejected # 3 spark plug. I immediately pulled off the hwy and seen that the plug had been ejected, a dented hood, and a some antifreeze had sprayed out from somewhere ( about 1/2 cup ). No smoke was coming out the tailpipe, it appears the antifreeze did not come out of the spark plug opening because there was no antifreeze on the underside of the hood next to the dent created from the spark plug ejection or on the plug&wire. All the threads on the spark plug were there, but all threads in the Aluminum head were fully gone. The GAP on the spark plug had been fully closed as though it was hit from a cylinder head? I know that you can cut steel with water, so with enough speed/pressure/& timing I'm sure anitfreeze could close a gap on a plug in the right conditions. The car is not worth much ( we're still original owners, & my dad was a Master Mechanic and taught me over the years as much as he could before passing away ) so towing it was not an option. I disconnected wire #3 and had my wife follow me home. Again on the flattest path home, which was approx. 13 miles, the car continued to start up fine and the other 3 cylinders seemed o.K. ) Except for the idle & crank balance. During this drive home ( approx 83 degrees ambient temp. ) The car did not run above normal operating temp, no smoke coming from anywhere, and the antifreeze leak did not leak again.
* Any help would be appreciated, Pops won't respond, via the other side. LOL. And I need some assistance now that he is in heaven and won't answer.
* What are your thoughts, besides ripping the engine down until I physically find out what happened?
* Also, is it possible that I may have blown the Head gasket seal on JUST #3, dump enough antifreeze in the cylinder on the down stroke, to crush the gap on the plug and then send flying into the hood? My first thought was the timing belt went, but that would have sent all the piston heads up into all the valves & spark plugs?

Thank you in advance,

The Grease Monkeys Son, Adam
Friday, May 14th, 2010 AT 2:40 PM

6 Replies

Tiny
MHPAUTOS
  • MECHANIC
  • 31,937 POSTS
Hi there,

The head will have to be removed to fix this problem, as far as a cause, often this is the result of a loose plug, a piston strike will not normally cause the plug to dislodge, things will normally just break and bend, a cooling system pressure test will show up any external coolant leak, if you drove it home the timing belt is fine, I would say this is a result of a loose plug.

Mark (mhpautos)
Was this
answer
helpful?
Yes
No
Saturday, May 15th, 2010 AT 3:43 AM
Tiny
MALMADAM
  • MEMBER
  • 4 POSTS
Thanks so much for the advise with a quick response. My family bloodline motto was always " keep your oil fresh, with clean air & fuel and to change the spark plugs often. I've had the honda since we drove it off the lot in 1996, i've changed the plugs probably 12 - 13 times ( once every 12 - 18 months ) always using antisieze lube and being gentle with the aluminum head. I guess I may have not have fully tightened one spark plug out of the posible 60 that have been replaced. Whoops. Again many thanks for helping me narrow this down. I guess it's time for me to learn how to do a Helio Coil.

The Grease Monkeys Son, Adam.
Was this
answer
helpful?
Yes
No
Saturday, May 15th, 2010 AT 10:08 AM
Tiny
MHPAUTOS
  • MECHANIC
  • 31,937 POSTS
HI there,

Just be real careful if you attempt to do this with the head on, as you don't want metal in the bore, even if it is only soft alloy.

Mark (mhpautos)
Was this
answer
helpful?
Yes
No
Saturday, May 15th, 2010 AT 10:23 AM
Tiny
MALMADAM
  • MEMBER
  • 4 POSTS
Wow you guys are quick ! Excellent service ! I watched pops do this procedure twice when I was young, and he helped his friend across the streettoo. They would get to TDC on whichever chamber they were working on, tap it, then catefully vacum out the shavings ( with what looked like a normal shop vac with a bunch of reducing hoses connected together. It always reminded me of a McGuyver show ). Heading to the part store now, any other hints to help jog my memory would be great.
Thanks Chief.
Was this
answer
helpful?
Yes
No
Saturday, May 15th, 2010 AT 10:35 AM
Tiny
MHPAUTOS
  • MECHANIC
  • 31,937 POSTS
Hi there,

and its 1-45 AM her in Aus, and I'm still at it. One last tip before bed time. Lol use a thick grease on the drill and tap, this will catch a lot of the swarf.

Mark (mhpautos)
Was this
answer
helpful?
Yes
No
Saturday, May 15th, 2010 AT 10:46 AM
Tiny
MALMADAM
  • MEMBER
  • 4 POSTS
I was starting wonder just how long your shift was because I was able to get your first response last night and then another quick response when I woke back up. Lol.
Many thanks from california.
Was this
answer
helpful?
Yes
No
Saturday, May 15th, 2010 AT 11:58 AM

Please login or register to post a reply.

Sponsored links