Leaky lofrans Kobra

GHA

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There's a little oil leaking out of the windlass - thinking it's probably this seal?

cX0SHtP.jpg


Or is the motor a tight fit so it acts as a seal?

h4eBhfn.jpg


So questions - if it is that seal anyone know if it's a stock part I could maybe source locally instead of trying to get a spares kit sent to Portugal?
Looks like parts kit 313?
H0YAM7d.png

Lofrans' Anchor Windlass Spare Parts

Or is it not a worry and the motor will create the seal when attached?

TIA
 
Why don't you get accurate measurements (using a vernier gauge) ID, OD and depth then look at one of the online catalogs such as

O Rings & Oil Seals: Rubber O Ring & Oil Seal Suppliers UK

You'll find it is atock item as no manufacturer would design their own seal!

NOTE It wouldn't apply in this case but some seals have to be the correct material as some will expand if immersed on sea-water. Have a look at this link as it may cover what I'm getting at.
Silicone vs Nitrile | Article | Jehbco Silicones

(Maybe Vyv Cox Engineering can explain it as I have long forgotten the requirements)
 
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The motor case is not sealed to the gearbox case.

It will be the seal 313. It should be a standard seal.

I always remove the seal and take it to my local seal supplier and let then sort it out.

If you can measure the o/ d of the shaft, the i/d do the housing and the width of the seal you may be able to locate one on the web.

I doubt that it will be a double lip so look for single lip seals

Also as its sealing oil in no need to a special spring.

SKF
 
You could just dip a piece of kitchen roll in white spirit and wipe it off. The rate at which a windlass turns, it's not going to wear out for lack of grease.

Sometimes we think too hard.
 
It is coming back to me now. I'm sure the bearing expert said that I had to use a Viton seal not a Nitrile.

Screenshot_2020-07-24 Pump Shaft Seal Heavy Duty (Saltwater Pools) - PS-3867 - INYOPools com.png
 
It is coming back to me now. I'm sure the bearing expert said that I had to use a Viton seal not a Nitrile.

View attachment 95278


No No No not for sealing oil

Sealing water pumps is OK. I fitted one of those to my pool pump last year.

The pool service company fitted one the wrong way round that still leaked ence I had to redo it my self.

There are similar to the PSS seal used on my boat and oil or grease must NEVER get on to the sealing surface.
 
It would go over the motor then drip off the bottom onto the chain in the anchor locker. Then a horrible grating sound as the gearbox seized running dry with no oil.
Some crazy ideas on here sometimes.. :)

Ok I forget that the Kobra as the motor under the deck. Me Tigres has its motor above the deck so ony oil would mess my deck up.

With your vertical motor if the oil seal fails ALL the oil would leak out but with mine it would not.
 
The shaft seal on my Quick windlass only last 6 years before it failed and covered everything with stinking hypoid gear oil. As soon I we arrived at the boat I could smell it. The level of oil in the windlass up to the fill/level plug is well above the level of the seal so a lot of oil came out over the winter when the windlass was never used.

I took out the old seal, looked at the measurements printed on the side, popped along to the marina maintenance yard and they sold me one from their stores for a few Euro. It was easy to replace it.

Richard
 
It would go over the motor then drip off the bottom onto the chain in the anchor locker. Then a horrible grating sound as the gearbox seized running dry with no oil.
Some crazy ideas on here sometimes.. :)
Well you did ask. You don't have to listen.
 
No No No not for sealing oil

Sealing water pumps is OK. I fitted one of those to my pool pump last year.

The pool service company fitted one the wrong way round that still leaked ence I had to redo it my self.

There are similar to the PSS seal used on my boat and oil or grease must NEVER get on to the sealing surface.

Where I had to use the the Viton seal was on the top of the rudder shaft from memory. I just wanted to make the point that a seal meant for oil/grease was not necessarily suited to a water pump seal.

Nitrile vs Viton® - What is the Difference? | Polymax Blog
 
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Where I had to use the the Viton seal was on the top of the rudder shaft from memory. I just wanted to make the point that a seal meant for oil/grease was not necessarily suited to a water pump seal.

Nitrile vs Viton® - What is the Difference? | Polymax Blog


Yes you are correct with regard to the type of rubber but the seal you posted not of oil seal it was a water seal even through the rubber parts were could be made of different types of rubber which have different rating against hydrocarbons

Thi is the type of seal the OP needs which as can be seen are available made from Nitrile or Viton

Oil Seal Type A - Fully Covered with Nitrile or Viton
 
Yes you are correct with regard to the type of rubber but the seal you posted not of oil seal it was a water seal even through the rubber parts were could be made of different types of rubber which have different rating against hydrocarbons

Thi is the type of seal the OP needs which as can be seen are available made from Nitrile or Viton

Oil Seal Type A - Fully Covered with Nitrile or Viton
Yes, when I wanted a seal for my rudder stock I found one with exactly the right dimensions and as about to order one when the online representative pointed out I was buying a seal meant for oil an grease and said I needed a Viton seal. I just didn't want GHA to order the wrong type
 
Yes, when I wanted a seal for my rudder stock I found one with exactly the right dimensions and as about to order one when the online representative pointed out I was buying a seal meant for oil an grease and said I needed a Viton seal. I just didn't want GHA to order the wrong type

Viton is over fill for normal oil sealing. Its only required when sealing against some particular environment and aggressive chemicals like ozone or when UV can degrade the seal.

I don't have a seal on my rudder stock I extended the rudder tube to above the water line with my steering cylinders above that just under the deck head.
 
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