Anode Thread size???

[Trevthefox]

This might be a question hard to answer but I can't for the life of me figure out the right size for the anode bolt on the outdrive. I have an 89 7.5 l 460 King Cobra. I recently bought a new anode for the outdrive. However, the original anode was not there nor was the bolt to hold it in.

It's part number 0332746 - L/P and to my luck its nowhere available online. I figured I could go and grab one at a hardware store but none of the threads match up. The 5/16 thread goes in about 1 full turn. I also tried metric (can't remember the size that fit best). What am I missing?

Any thoughts? Check out the diagram to see which anode I'm talking about.

Thanks

 

[dingbat]

There are course (5/16-18 unc) and fine (5/16-24 unf) thread screws.

5/16-18 is the most common
5/16-24 is a “specialty” screw

 

[Trevthefox]

There are course (5/16-18 unc) and fine (5/16-24 unf) thread screws.

5/16-18 is the most common
5/16-24 is a “specialty” screw

Hey thanks for replying,

I actually tried both. The 5/16-18 fit better, but only 1 rotation. The inner threads seem to be fine, no signs of previous cross threading

 

[Horigan]

You can try chasing the threads with a 5/16-18 tap. If that jams up you can drill it out and install a helicoil for 5/16-18. That's what I did when my mounting threads were corroded.

 

[Trevthefox]

You can try chasing the threads with a 5/16-18 tap. If that jams up you can drill it out and install a helicoil for 5/16-18. That's what I did when my mounting threads were corroded.

Thanks Rich,

I'll give that a shot

 

[Trevthefox]

You can try chasing the threads with a 5/16-18 tap. If that jams up you can drill it out and install a helicoil for 5/16-18. That's what I did when my mounting threads were corroded.

Figured I'd give an update. Used a 5/16-18 tap. Worked like a charm.

Thanks

 

[Horigan]

Excellent!

 

[Lou C]

Great work!
A good tip is coating the threads of all the fasteners on the drive with OMC gasket sealer, Merc Perfect Seal or Permatex Aviation. I have been doing this for years and have not had trouble with seized threads, even though my outdrive has been in salt water for 6 months out of the year most seasons.