300 I6 Spark Plug choice

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Feb 16, 2020 | 11:26 AM

yarddogg77

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Joined: May 2019

Posts: 237

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From: Pasco, WA

300 I6 Spark Plug choice

So far I have had 2 sets of plugs for my 300. Neither set have come with soft washers for some reason. Both set's have loosened up in the hole. Seems every time I check them I have loose plugs again. Is there some reason why spark plugs are not fitted with the base washer on this engine? Almost every other spark plug I have bought for other engines have had them. Can anybody recommend a plug that will stay tight on the holes? I have a vacuum advance distributor with magnetic pickups, an Accel coil, and will soon be converting it to HEI.

Feb 16, 2020 | 02:23 PM

Kramercd

Cargo Master

Joined: Jan 2019

Posts: 3,369

Likes: 16

From: Caraway, AR

I always get the $2 recommended plugs. The cast iron is bad about letting hardware back out. It'd retorque them after a few heat cycles.

Feb 16, 2020 | 02:49 PM

yardbird

Logistics Pro

Joined: Dec 2003

Posts: 3,777

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From: Foothills of NC

Ford, for some unknown reason, keeps on using taper seat spark plugs, even though they are more prone to work loose than washer seal plugs.

Nov 25, 2023 | 07:20 PM

Weberda328jw

7th Gear

Joined: Mar 2018

Posts: 7

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Ford 300. 6 /

Quote:

Originally Posted by yarddogg77

. I personal used y14 f champion had 9 years bad luck autolite motorcraft sturdy on copper now ordered ngk v plus copper as well all my life champion ,,,, I'm 55 not still get checked normal blue 8mm and duraspark brass motor craft rig run optimum one barrel great on gas better then any I've ever had get fixing for none ping and octane mix running awesome hei duraspark 2 are very similar in all areas