Why am I replacing woodruff key???????

[crazy charlie]

2000 200hp Saltwaterseries OX66 2 stroke. GREAT MOTOR!!! did 2 water pump services since I got it a few years ago. Extremely difficult to remove woodruff key during water pump servicing. Extremely difficult to replace new woodruff key .Had to sand new key to make it fit this spring.WHY dont I just leave the old key in place?????? Why am I replacing it????? seems like a Pia that I can do without if no harm done.?????? Charlie

 

[mike_i]

They are a PITA to replace. I've replaced my water pump several times without replacing the woodruff key.

2000 200hp Saltwaterseries OX66 2 stroke. GREAT MOTOR!!! did 2 water pump services since I got it a few years ago. Extremely difficult to remove woodruff key during water pump servicing. Extremely difficult to replace new woodruff key .Had to sand new key to make it fit this spring.WHY dont I just leave the old key in place?????? Why am I replacing it????? seems like a Pia that I can do without if no harm done.?????? Charlie

 

[dingbat]

2000 200hp Saltwaterseries OX66 2 stroke. GREAT MOTOR!!! did 2 water pump services since I got it a few years ago. Extremely difficult to remove woodruff key during water pump servicing. Extremely difficult to replace new woodruff key .Had to sand new key to make it fit this spring.WHY dont I just leave the old key in place?????? Why am I replacing it????? seems like a Pia that I can do without if no harm done.?????? Charlie

Guessing

The key is intentionally softer than the shaft to absorb the impact should anything bind up the impeller. Typically a low carbon steel.

The drive shaft is typically a 4xx series stainless. The impeller typically has a bronze hub so you have a dissimilar metals situation.

With the key being less noble than the other materials, it’s the first to corrode.

If corrosion starts down in the key way, it’s never coming out

 

[crazy charlie]

Guessing



If corrosion starts down in the key way, it’s never coming out

And??????

 

[Captain Caveman]

The issue of course is that if it corrodes and then snaps, you're really going to have a problem removing the part of the key that is sitting in the depression on the shaft.

I just replaced the water pump on my DF90 last week. The key fell out as soon as I pulled up on the impeller. It really shouldn't get stuck in there.

 

[cyclops222]

Mine are loose also.

 

[crazy charlie]

The issue of course is that if it corrodes and then snaps, you're really going to have a problem removing the part of the key that is sitting in the depression on the shaft.

I just replaced the water pump on my DF90 last week. The key fell out as soon as I pulled up on the impeller. It really shouldn't get stuck in there.

Mine are loose also.

woodruff keys in this application are supposed to be tough to apply and tougher to remove. If yours "fell out" it either was incorrect woodruff key or not installed properly.

 

[Captain Caveman]

woodruff keys in this application are supposed to be tough to apply and tougher to remove. If yours "fell out" it either was incorrect woodruff key or not installed properly.

How do you not install a key properly? I can 100% guarantee that the key was specified for my motor.

 

[crazy charlie]

How do you not install a key properly? I can 100% guarantee that the key was specified for my motor.

Tell us exactly how you installed the key and after that I will give you the answer.