Galded threads on lower unit

[yammyman]

I have some galded threads in the lower drainplug on my 1991 70hp Johnson. The plug was tight. Once it broke loose it backed out like normal. When I went to put it back in it would tighten as soon as it started. I can see that the threads are all galded up.

How would ya'll go about fixing them?

 

[SumDumGuy]

Re: Galded threads on lower unit

If it was a standard size I would run a tap through it.

If that is not doable or will not repair then I would consider a helicoil.

 

[orbanp]

Re: Galded threads on lower unit

Are you sure you have not cross threaded it? Coming out normally and going in tight right away would indicate that!
If you use a tap and die to clean up the threads be extremely careful not to cross thread them! Start with the plug, at least that can be replaced cheaply.

Peter

 

[boobie]

Re: Galded threads on lower unit

Run a thread chaser or tap through the threads in the lower unit. I think it's a 3/8-18 NC thread size. Then get a new drain plug and gasket. If that doesn't work, it's heli-coil time.

 

[yammyman]

Re: Galded threads on lower unit

Thanks fellas. I will try the chaser first. I am positive it is the threads.