Spark plug wrench size

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daan.ce

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Hello community

I am planning to do my first ever car maintenance so I'm an absolute newbie. I haven't bought any tools yet, so I'm trying to find out which tools I need to order.

I'm having the most trouble finding the correct wrench size for replacing the spark plugs. Based on what's in the manual of the car, I need the following plugs:

NGK LMAR8K-9S (https://www.ebay.co.uk/p/24045086925)

I've tried to find the correct size using the following chart, but de name of the plug doesn't really seem to correspond with the letters in the table.
1693411321798.png


Anyone who could help?

Thanks
 
Spark plug sockets are governed by their thread diameter, 14, 16 and 18mm. Other references are to the actual socket diameter.
That plug looks like a 14mm one, it could be a good idea to buy one with a rubber insert that grips the plug on removal, or better still, a magnetic one. As many plugs are deep down into a counterbored hole, a thin wall socket may be best.
Laser tools have what you need, number 7295.
John
 
Yep, 14mm hex on that plug.
I don't use a socket with a rubber insert as, sometimes the rubber stays on the plug, instead of staying in the socket. I just use a deep 14mm socket to slacken the plug until it is almost out then I undo the last threads with an old piece of servo hose.
To put the plug back in, insert it into the servo hose and thread it in. The hose will grip it tight enough to turn it but not tight enough to put it in on the wrong thread.
 
After loosening a plug that’s set deep in the head, I always use the actual plug lead to pull it out.
 
Stivino said:
Yep, 14mm hex on that plug.
I don't use a socket with a rubber insert as, sometimes the rubber stays on the plug, instead of staying in the socket. I just use a deep 14mm socket to slacken the plug until it is almost out then I undo the last threads with an old piece of servo hose.
To put the plug back in, insert it into the servo hose and thread it in. The hose will grip it tight enough to turn it but not tight enough to put it in on the wrong thread.
Click to expand...
Thank you for confirming, plug replacement is what I'm stressing most about. I'll try the trick with the servo hose. Looks like there's a lot to replacing spark plugs. Will do some extra research before attempting it.
 
Nothing to really stress about, get stuck in!
These plugs have a crush washer, so you can feel when they are tightening up.....unlike the tapered seat plugs of old, which occasionally would snap off - remember Fiesta days, anyone?
daan, are there ignition coils on top of the spark plugs? Give us a pic and we’ll take you through that.
John
 
Burnerman said:
Nothing to really stress about, get stuck in!
These plugs have a crush washer, so you can feel when they are tightening up.....unlike the tapered seat plugs of old, which occasionally would snap off - remember Fiesta days, anyone?
daan, are there ignition coils on top of the spark plugs? Give us a pic and we’ll take you through that.
John
Click to expand...

Hi John

There should be the following ignition coils:


It's for a Fiat 500 1.0 mild hybrid (yes this car is slow as f..)

Most online guides are for older Fiat 500 models, which have 6/8" spark plugs.

I can only find a 12 point 9/16" socket. The 6 point wrenches are all 6/8". Does the 12 point work with the 6 point spark plug?

Thanks
 

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Maybe I have ocd, but I always torque the spark plugs to the correct torque, usually printed on the box.
 
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