loose spark plug
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Joined: 06 Oct 2018
Posts: 145
Location: Gravesend, Kent, UK
Fri Jul 05, 2019 4:04 pm quote
Hello. Today's problem is I have a PX125E which every time I check the spark plug it's loose.

I've tried replacing the washer every time, tightening it to the manufactures spec, over tightening it but no, the bloody thing wont stay put. Any suggestions please?
2018 LIBERTY 150S
Joined: 26 Jul 2013
Posts: 849
Location: Ohio
Fri Jul 05, 2019 4:15 pm quote
Is it stripped, from overtightening?

1955 Allstate 1958 lambretta 1965 Allstate 1968 sprint
Joined: 20 Jul 2017
Posts: 381
Location: Central california
Fri Jul 05, 2019 4:32 pm quote
Spark plug loose
Well certainly over tightening a spark plug can lead to stripping of the spark plug hole, but what else can happen is that the spark plug is not tightened enough. If a new plug is used and the spark plugs gasket is not crushed when tightening down of the plug it will work itself loose, hence damaging the threads. Scott
bare metal cafe racer
Joined: 01 Sep 2017
Posts: 461
Location: Aotearoa (New Zealand)
Fri Jul 05, 2019 9:17 pm quote
Helicoil time?
Joined: 06 Oct 2018
Posts: 145
Location: Gravesend, Kent, UK
Sat Jul 06, 2019 9:39 am quote
Plan B
Hello. Thank you for your replies.
I checked the plug and head. both look OK.
The NGK box says to tighten the plug 1/2 to 2/3 turn with a new washer.

I did a bit of digging and found this. The NGK website gives torque settings of 18 to 22 ft-lb (2.5 to 3.0 Kg-m). That's a lot more than 1/2 a turn. We'll see what happens now.
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