Forums
NautiqueParts.comNautiqueSkins.com - Correct Craft Upholstery and Part
  New Posts New Posts RSS Feed - Spark plug blew up!???
  FAQ FAQ  Forum Search   Register Register  Login Login

Spark plug blew up!???

 Post Reply Post Reply   
Author
adkrock View Drop Down
Newbie
Newbie


Joined: July-22-2018
Location: Adirondack Mtns
Status: Offline
Points: 4
Post Options Post Options   Thanks (0) Thanks(0)   Quote adkrock Quote  Post ReplyReply Direct Link To This Post Topic: Spark plug blew up!???
    Posted: July-22-2018 at 7:38pm
Went for a ride last night in my 98 SNOB and cruising at 44mph. There was a 2mph drop in speed and then BANG! and pop pop pop pop. The ceramic part of a spark plug blew out and the threaded end stayed put. The popping was from the plug leaving a hole over the piston.

Anyone have any ideas what caused this?

Thanks!
adkrock
Back to Top
KENO View Drop Down
Grand Poobah
Grand Poobah


Joined: June-06-2004
Location: United States
Status: Offline
Points: 10606
Post Options Post Options   Thanks (0) Thanks(0)   Quote KENO Quote  Post ReplyReply Direct Link To This Post Posted: July-22-2018 at 8:02pm
Did all of the plug insulator including the center electrode blow out or did some of it stay in the cylinder.

I imagine you found the piece or pieces that blew out.

A picture would go a long way toward maybe answering the "why"

if you have any internal damage, it's already happened so a compression test would be a good start to see if there's damage.
Back to Top
Duane in Indy View Drop Down
Platinum Member
Platinum Member
Avatar

Joined: October-26-2015
Location: Indiana
Status: Offline
Points: 1578
Post Options Post Options   Thanks (0) Thanks(0)   Quote Duane in Indy Quote  Post ReplyReply Direct Link To This Post Posted: July-22-2018 at 9:46pm
Bet it was not near as exciting as this plug failure was. The part on the right was the piece that was left threaded into my cylinder head   Notice you can see the electrodes thru the hole.
Oh, by the way, it happened at about 3000 feet on takeoff in my plane. All came out good. Sure needed to change clothes though

Keep it as original as YOU want it
        1978 Mustang (modified)
Back to Top
gun-driver View Drop Down
Grand Poobah
Grand Poobah


Joined: July-18-2008
Location: Pittsburgh, Pa
Status: Offline
Points: 4112
Post Options Post Options   Thanks (0) Thanks(0)   Quote gun-driver Quote  Post ReplyReply Direct Link To This Post Posted: July-22-2018 at 10:22pm
That's why you shouldn't be in the air in anything that has plugs and carbs.
Back to Top
75 Tique View Drop Down
Grand Poobah
Grand Poobah
Avatar

Joined: August-12-2004
Location: Seven Lakes, NC
Status: Offline
Points: 6097
Post Options Post Options   Thanks (0) Thanks(0)   Quote 75 Tique Quote  Post ReplyReply Direct Link To This Post Posted: July-22-2018 at 10:24pm
Exact same thing happened to me many years ago, with the added excitement of a fire under the engine cover. Same thing, ceramic section shot out of the metal base. Ignited gas followed. No damage. Was attributed to a plug not tight in the socket. Dont know if that is a real thing or not or if mine was really loose. I was concerned about debris in the cylinder. It was scoped and appeared to be fine. Ran it, and it was. But it did get my attention (tho probably not to the extent had it happened in a plane)
_____________
“So, how was your weekend?”
“Well, let me see…sun burn, stiff neck, screwed up back, assorted aches and pains….yup, my weekend was great, thanks for asking.”
Back to Top
MACS81SN View Drop Down
Senior Member
Senior Member
Avatar

Joined: May-27-2009
Location: NW OH / S. MI
Status: Offline
Points: 109
Post Options Post Options   Thanks (0) Thanks(0)   Quote MACS81SN Quote  Post ReplyReply Direct Link To This Post Posted: July-22-2018 at 11:40pm
For what it’s worth, my $.02 is that it’s a defective plug.   Toured the Champion spark plug plant in high school.   Plug is assembled by inserting metal seal, gasket, electrode, and insulator into the top the of the metal shell.   Everything held together by a small rolled crimp on top of shell. Probably a bad crimp that held for awhile.

Decided during tour that I was never going to work on a factory assembly line. Never did.
Mark

1999 -SN - 502 Python
1981 - SN Owned 33 years - Sold
1968 - Mustang - Sold



Back to Top
gt40KS View Drop Down
Gold Member
Gold Member
Avatar

Joined: August-05-2017
Location: Wichita Kansas
Status: Offline
Points: 943
Post Options Post Options   Thanks (0) Thanks(0)   Quote gt40KS Quote  Post ReplyReply Direct Link To This Post Posted: July-22-2018 at 11:43pm
Several possibilities come to mind as to a cause. Suffice to say a little research would be prudent before simply installing another plug and firing it up. One thought that comes to mind is a lean condition during high rpm run that ultimately caused a detonation. If so, the plug blow-out was a lucky outcome - could have been much worse. I'd pull the other plugs to see their color & condition as a start. Any engine work done recently?
JCCI
1995 Ski Nautique GT40
Back to Top
Duane in Indy View Drop Down
Platinum Member
Platinum Member
Avatar

Joined: October-26-2015
Location: Indiana
Status: Offline
Points: 1578
Post Options Post Options   Thanks (0) Thanks(0)   Quote Duane in Indy Quote  Post ReplyReply Direct Link To This Post Posted: July-23-2018 at 12:11am
In my case I attributed the failure to the radius in the corner being too sharp and causing a stress riser. Of course Autolite never would agree but they did send me 12 new plugs. Not bad considering over $20 each. (They also kept my failed plug)
Keep it as original as YOU want it
        1978 Mustang (modified)
Back to Top
adkrock View Drop Down
Newbie
Newbie


Joined: July-22-2018
Location: Adirondack Mtns
Status: Offline
Points: 4
Post Options Post Options   Thanks (0) Thanks(0)   Quote adkrock Quote  Post ReplyReply Direct Link To This Post Posted: July-23-2018 at 12:18am
Thanks for all the feedback! Will do a compression test and take a look at other plugs. Hoping there is no cylinder damage. Was suggested by a friend mechanic that it does occur but rarely. Got a week of rain in the forecast so plenty of time for diagnostics.

Thanks again!!
adkrock
Back to Top
Duane in Indy View Drop Down
Platinum Member
Platinum Member
Avatar

Joined: October-26-2015
Location: Indiana
Status: Offline
Points: 1578
Post Options Post Options   Thanks (0) Thanks(0)   Quote Duane in Indy Quote  Post ReplyReply Direct Link To This Post Posted: July-23-2018 at 12:21am
Originally posted by gun-driver gun-driver wrote:

That's why you shouldn't be in the air in anything that has plugs and carbs.


Oh now that's funny   I worked very closely with the Failure Analysis Department with Allison Engine Company later known as Rolls Royce. You can usually limp back home with a dead cylinder but not with a turbine that spit blades out the exhaust. (at least with a single engine turbine) Saw many turbine engine failures, fortunately most were on the test stand.
Keep it as original as YOU want it
        1978 Mustang (modified)
Back to Top
gun-driver View Drop Down
Grand Poobah
Grand Poobah


Joined: July-18-2008
Location: Pittsburgh, Pa
Status: Offline
Points: 4112
Post Options Post Options   Thanks (0) Thanks(0)   Quote gun-driver Quote  Post ReplyReply Direct Link To This Post Posted: July-23-2018 at 12:37am
That’s why we have two
Back to Top
adkrock View Drop Down
Newbie
Newbie


Joined: July-22-2018
Location: Adirondack Mtns
Status: Offline
Points: 4
Post Options Post Options   Thanks (0) Thanks(0)   Quote adkrock Quote  Post ReplyReply Direct Link To This Post Posted: July-24-2018 at 8:33am
554045175.jpg
Tried to post a pic and this is all that came up. How do you post a pic from your pictures?
adkrock
Back to Top
8122pbrainard View Drop Down
Grand Poobah
Grand Poobah
Avatar

Joined: September-14-2006
Location: Three Lakes Wi.
Status: Offline
Points: 41040
Post Options Post Options   Thanks (0) Thanks(0)   Quote 8122pbrainard Quote  Post ReplyReply Direct Link To This Post Posted: July-24-2018 at 8:58am
Rockne,
Use the post reply or click on the full reply editor icon (arrow pointing to 2 o'clock) to open up all icons. Then click the tree with the up arrow icon. A browse box will come up allowing you to select anything off your computer.


54 Atom


77 Tique

64 X55 Dunphy

Keep it original, Pete
<
Back to Top
 Post Reply Post Reply
  Share Topic   

Forum Jump Forum Permissions View Drop Down

Copyright 2024 | Bagley Productions, LLC