Car spark plug stuck...help | GTAMotorcycle.com

Car spark plug stuck...help

Hawk

Well-known member
Son in law has his old Saab at a mechanics and they can't get one plug out. They're broken off the insulator trying. Soaked it for days in WD40 and today got a "specialist" in to try and get it out but failed after 2 hours they say. Nobody is saying what this specialist tried, maybe it's his trade secret. Does another have any suggestions before the car is sent to scrap because he can't afford to buy another car. Thanks
 
WD-40 "Specialist"??
There are several products in that category including deep penetrating oil...sort of like liquid wrench...
Speaking of wrench - you should attach 1/4 drive bit to spark plug socket and try releasing the threads with impact gun...usually works breaking free seized threads
give it a shot...good luck!


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WD40? Ack... First problem, right there. And I'd question any proper mechanic who breaks off the insulator from a spark plug - that's a rookie mistake caused by someone who didn't have their socket on the plug correctly to begin with.

First off, they need to start with a real penetrating oil like PB Blaster.

Secondly, if they can get a torch in there somewhere close to the plug, heat up the cylinder head but not the plug itself. You want the head (and plug threads) to expand, but not the plug itself. Works wonders - science is amazing. Any decent mechanic should know this.

If that doesn't work...there's always the option of pulling the head and drilling the damn plug out...but I'm going to guess since it's already on the edge of going to scrap as it is that exceeds the value of the car potentially?
 
There is an extractor for that.

... if you mess up the threads there is a heli coil repair for that too,
considerable hazard of getting crap down inside the motor :| that's a little hard to prevent
a little compressed air might be in order before putting new plugs in, you might get lucky and blow any bits out.
 
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is the nut portion also broken off?
if so, gonna have to find an extractor, or take the head off
if not you still have socket options left, including some gentle heat
I'm guessing it's in a nasty spot
 
Saab is a boxer engine isn't it? Hard to get at is probably why it got broken to begin with.
 
Only the "Saabaru" (9-2X) which was a Subaru underneath, had a boxer engine.

The rest of us don't know "which" old Saab. If it was a GM Saab, it could be one of several GM engines. If it was a "real" Saab from before GM, it will have an in-line four. If it was an "original" Saab, it will have a two-stroke engine or a Ford V4, but if it were one of those, we wouldn't be talking about scrapping the car over a stuck spark plug!

Try the extractor tool.

If you end up having to drill and re-tap, do it with the piston at TDC on the compression stroke and DON'T drill too far (don't drill a hole in the piston - measure twice, cut once). Coat the drill with grease and when done drilling, blast out the combustion chamber first with solvent for a couple seconds then with compressed air. Coat the tap generously with grease.
 
Ask for Henry at Jeremy's Auto on Queen street east. He knows the old saab's.
 
As others have said before, I'm not impressed with what has already been tried.

Good penetrating oil, heat and a big lever will get it out.

Javafan, have you ever seen a spark plug shear off between the nut and threads? I haven't and didn't think it was possible, but if you've seen it, that's terrible luck.
 
I happens more than you think, , different metals in head vs. spark plug and if they aren't in/out regularly they galvanic corrode in the hole and snap off at the threads. Depending on engine pulling the head can be an expensive deal, costing much more than the car is worth.

Its possibly/probably an aluminum head, getting a torch in there will likely result in head gasket leak shortly. You could probably spray any "release agent' in there for weeks , its chemically bonded in the hole. Given the working angles on some of those engines its no wonder insulators snap. ( Chev monza where the engine had to be lifted 9" to change the last plug, 99% never had plug 8 changed)

The shop isnt going to heat the head, or likely want to drill it out, in two weeks when the valve train finds drill swarf, or the head gasket goes THEY have a 2-5k repair bill on a 1k car.
 
Thank you for all the suggestions, I've passed them along. Son in laws mechanic said he's going to try again today. The car is 2003 Saab 9-5 2.3L turbo. I will post the end result of all this.
 
This guy does an interesting comparison of penetrating fluids. PB Blaster does not actually come out all that great. This is rusted steel, not galvanic corrosion, though.
[video=youtube;xUEob2oAKVs]https://www.youtube.com/watch?v=xUEob2oAKVs[/video]
 
back when I was on the tools
best luck I had was with some stuff called Moovit
was sold by Acklands, never seen it at a retail outlet
 
This guy does an interesting comparison of penetrating fluids. PB Blaster does not actually come out all that great. This is rusted steel, not galvanic corrosion, though.
[video=youtube;xUEob2oAKVs]https://www.youtube.com/watch?v=xUEob2oAKVs[/video]

Link to results in that video. https://youtu.be/xUEob2oAKVs?t=516

AVE did a test on rusted steel too. IIRC PB Blaster also did poorly in his test.
 
I'm so glad this has never happened to me
 
had the same thing happen to me with a 350 small block (champion plug & never forgot it). ceramic broke but not from slipping socket...the plug twisted and caused ceramic to break. no champion plugs for me...I like NGK ty lol

torched it NEAR red hot and it came out easy ...but the head wasn't aluminum. I was worried the heat may have caused other damage, but drove the car for years after, with no ill effects. got to luv a small block with good old iron heads.

wd40 is not a good penetrating oil.

if you have an aluminum head you NEED to be using anti sieze on the plugs. actually, I use anti sieze - iron or aluminum heads-is a good practice...

best luck.
 
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had the same thing happen to me with a 350 small block (champion plug & never forgot it)

Ahahaha... should have added I worked a CT parts counter when they still sold Champion plugs. That alone made sure I never used them, but still kept me up at night after installing other better plugs
 

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