Block heater plug thread size

[incisor]

Anyone know what size / thread the block heater plug is?

[fc110]

Anyone know what size / thread the block heater plug is?
1" NPT, I use stainless steel ones, take em out & use on the next engine!

[incisor]

1" NPT, I use stainless steel ones, take em out & use on the next engine!

pretty much what i will be doing as well :p

thankyou for the info...

[Andwoo]

I just put a 3/8 Bsp plug in my series 3 to block up the heater point on the rear of the block... ?

Edit: just read your other thread, different plug!