Raw water pump seal seating question

[AndyL]

Hello,

I am installing a new seal on an old Johnson raw water pump from my 3GM30. The seal is an EAI VITON Oil Seal 12mm X 24mm X 7mm (https://www.amazon.com/gp/product/B07NKWV8PF).

I used a variety tools to press it in, applying a good amount of force in an attempt to fully seat it. I can't get it completely flush with the back of the housing. You might be able to see in the picture that it protrudes slightly - something around 1mm or less - hard to measure.

I am hesitant to move to the next level tools and apply a lot more pressure in case I break something.

Does it need to be completely flush?

 

[Roland5048]

I think you might be overthinking this. My thought is that if it were perfectly flush, how would it form a seal? I would just put everything back together and start her up and see if it leaks. You will know right away. No water out the back indicates an air leak. If that happens shut it down immediately. Go back to square one. When you put the bolts in don't tighten in succession. Tighten across from each other to keep from warping the face plate. I really think you are going to be OK, providing you have the correct O-ring.

 

[kloudie1]

A few thousandths won't hurt anything.. Is the back of the housing worn down enough to cause the seal to not fit flush? Check by comparing the protrusion away from the cam to the protrusion between the two ports on the cam.

 

[AndyL]

Thanks - this is actually a used spare pump the PO left on the boat so I won't be installing it. I assume it was removed for some reason but nothing looked obviously wrong when I took it all apart. I read that sometimes it's shaft wear and using a double lip seal can help with that.

Hopefully I'll never need it anyway. For now, I will assume it is OK as a spare and stop obsessing about it.

 

[Roland5048]

If you can, take it to a place that can refurbish it. Less than half the the price of a new one and you'll have a reliable spare. Never assume anything.