Generic parts for Johnson raw water pump - an apology

Danny Jo

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Last year I said that there appeared to be no difference between a standard oil seal and a Johnson raw water pump shaft lip seal (see this thread)

I am sorry to report that I have been proved wrong.

Before launching last week, I replaced my impeller and filled the raw water circuit by pouring water in at the raw water strainer and allowing it to run back to the intake seacock, which I then shut off. The pump leaked.

When I disassembled it, I found that the spring in the lip seal had rusted through in several places. Closer comparison of the lip seals supplied as replacement Johnson parts by Aquafax with another of the generic oil seals from the local supplier of bearings and seals showed that the Johnson seal had a bronze-coloured spring, while the oil seal had a steel-coloured spring.

If anyone acted on the basis of the information in my post, my apologies, but take a good look at your pump seal.

Happy sailing!
 

vyv_cox

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My experience has been very similar.

The seals failed on the raw-water pump on my Yanmar 3GM30 a couple of years ago. When I replaced them, at Ionian Yacht Assist in Nidri, they pointed out that the Yanmar seals have a brass or bronze spring, whereas the otherwise identical Volvo seal has a stainless steel spring. I bought the Volvo ones, which amazingly were cheaper!

On my return to UK I bought spare seals from Marine Power Ltd, they helpfully pointed me to another, much cheaper alternative, also with a stainless spring.
 

sailorman

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Last year I said that there appeared to be no difference between a standard oil seal and a Johnson raw water pump shaft lip seal (see this thread)

I am sorry to report that I have been proved wrong.

Before launching last week, I replaced my impeller and filled the raw water circuit by pouring water in at the raw water strainer and allowing it to run back to the intake seacock, which I then shut off. The pump leaked.

When I disassembled it, I found that the spring in the lip seal had rusted through in several places. Closer comparison of the lip seals supplied as replacement Johnson parts by Aquafax with another of the generic oil seals from the local supplier of bearings and seals showed that the Johnson seal had a bronze-coloured spring, while the oil seal had a steel-coloured spring.

If anyone acted on the basis of the information in my post, my apologies, but take a good look at your pump seal.

Happy sailing!

when i changed mine a local factor got me ones with s/s springs
 

sokari

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Generic seal fix

Hi guys

I know this is a bit late for some of you,
The way to get around the problem you are having with generic seals,
remove spring in seal and replace with similer sized O ring.

I have done it for 16 years and no problems .

Regards
John
 
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