What size socket wrench fits my spark plugs?

Cuppy420

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Yamaha T50TLRB 50 HP 4-stroke
I can't get a regular spark plug socket in there to tell
 

airshot

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Measure across the flats on the plug body and that will be your socket/ wrench size.
 

rolmops

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These outboards usually come with a small toolkit and there is a sparkplug socket in it. It usually is a 14 millimeter socket. If the socket itself is too fat, you should try a chainsaw socket. Those are often thinner. the plug you need is a Ngk DPR6EB-9
There are a few setups that need an 18 millimeter socket .
 
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Cuppy420

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These outboards usually come with a small toolkit and there is a sparkplug socket in it. It usually is a 14 millimeter socket. If the socket itself is too fat, you should try a chainsaw socket. Those are often thinner. the plug you need is a Ngk DPR6EB-9
There are a few setups that need an 18 millimeter socket .
Yup! It's an 18mm...chainsaw socket is exactly what I need
 

99yam40

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3/4" deep socket should fit, might need to grind down the walls if too thick.
saying all of them does not say anything about what sizes you tried
 

Cuppy420

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3/4" deep socket should fit, might need to grind down the walls if too thick.
saying all of them does not say anything about what sizes you tried
I just tried normal spark plug sockets. The problem is the thick wall won't even get down to where I need to use it. Going to stop by Harbor Freight tonight and pick up a chainsaw 18 mm socket
 

rolmops

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The plug that is in there might not be the proper one for your engine. Yamaha is a very good company and a plug socket not fitting should be a red flag as to whether the plug was just shoved in there because it was what was available when last the plugs were changed. Check out your manual or online to see if it was the wrong plug to begin with.
Yamaha sells their own sparkplug sockets. You can get them on Ebay for about $20 ,they have a thin wall. These sockets will not damage the plugs. Chain saw sockets work ,but you may not be able to get them deep enough ,because the c1729630514838.pngrossbar will probably get in the way.
 
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Cuppy420

Petty Officer 3rd Class
Joined
Oct 20, 2024
Messages
79
The plug that is in there might not be the proper one for your engine. Yamaha is a very good company and a plug socket not fitting should be a red flag as to whether the plug was just shoved in there because it was what was available when last the plugs were changed. Check out your manual or online to see if it was the wrong plug to begin with.
Yamaha sells their own sparkplug sockets. You can get them on Ebay for about $20 ,they have a thin wall. These sockets will not damage the plugs. Chain saw sockets work ,but you may not be able to get them deep enough ,because the cView attachment 402813rossbar will probably get in the way.
Thanks for the tip! I'll look at that tonight
 
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