What is thread size at block for the water temp sending unit? I have 115 hp mercury 2 stroke. S/N 0G163946

[gja396]

What is thread size at block for the water temp sending unit? I have 115 hp mercury 2 stroke. S/N 0G163946

 

[alldodge]

It will be NPT (national pipe thread) in either 1/4 or 3/8
Measure the whole 1/4 will be close to 1/2 OD and the 3/8 will be 5/8 OD