Nitrile or Neoprene pump service kit?

[graham]

I have a Whale Gusher 10 bilge pump in the Lazarette locker. The service kits say use Nitrile diaphragm for below deck and neoprene for above deck installation.

Anyone know why the difference and does in a cockpit locker count as above or below decks?

 

[Old Harry]

nitrile will cope with oily bilges

 

[VicS]

I have a Whale Gusher 10 bilge pump in the Lazarette locker. The service kits say use Nitrile diaphragm for below deck and neoprene for above deck installation.

Anyone know why the difference and does in a cockpit locker count as above or below decks?

A quick google found this page.. Nitrile vs. Neoprene: Which Rubber Material Is Best? | Thoams A. Caserta.

 

[LittleSister]

I have a Whale Gusher 10 bilge pump in the Lazarette locker. The service kits say use Nitrile diaphragm for below deck and neoprene for above deck installation.

Anyone know why the difference and does in a cockpit locker count as above or below decks?

I think that the 'below decks' thing is about what you are pumping. As Old Harry says, nitrile copes better with oil, etc. So if you are pumping bilges, or anything else likely to have oil, chemicals, etc. in it, then regardless of where the pump itself is located, use nitrile. Otherwise use neoprene. (Perhaps it copes better with UV?)

Your question related to a diaphragm pump. In regard to impellers in centrifugal pumps (e.g. engine cooling seawater pumps), I've read that, again, use nitrile if there's a risk of chemicals or oil in what your pumping, but that if that is not a risk, then neoprene is preferable because it copes better if run dry.

 

[doug748]

I have a Whale Gusher 10 bilge pump in the Lazarette locker. The service kits say use Nitrile diaphragm for below deck and neoprene for above deck installation.

Anyone know why the difference and does in a cockpit locker count as above or below decks?

My experience makes me think Nitrile is dodgy.

When I changed my engine about 12 years ago I found the Johnson Nitrile impellers lasted only a season, were frequently damaged when removed, and often left debris in the heat exchanger:

09-810B-9 Johnson Pump F4B Impeller (Nitrile)

When I switched to Jabsco Neoprene this trouble disappeared:

Jabsco Impeller Kit 653-0001-P | Marine Super Store
utm_source=google_shopping&utm_medium=pcn&utm_term=01222&utm_campaign=MSS&gclid=EAIaIQobChMI6aOpsuGr6gIVyIBQBh3Ajwy_EAQYASABEgIVNfD_BwE

This winter I changed my Neoprene Jabsco after 4 seasons use, it was still intact.


The Henderson bilge pump I fitted about 4 years ago had a diaphragm fail at 2 years and I am starting to wonder if it was Nitrile as my Mk 5 heads pump still sports the same (maybe Neoprene) diaphragm for at least 25 years.

 

[Rocksteadee]

Some of this already mentioned:
Neoprene, hard wearing, stays flexible, less prone to U.v damadge, will self lubricate (to a degree ) when dry. Will swell up and go soft if exposed to oil fuel etc.
Nitrile, resistant to oil and fuel, wears quicker, goes hard and loses flexibility

 

[thinwater]

A flexible impeller pump and a diaphragm pump are very, very different. I would not compare experiences. Nitrile if oil is present, Neoprene can tolerate occasional oil and has a better flex life.

 

[graham]

Thanks for all the replies.got a neoprene kit today .This pump rarely pumps anything other than when being tested.

 

[joyfull]

Why are the whale diaphragm kits so expensive?

 

[bigshineybike]

I'm also wondering about the cost of new whale diaphragm spares.
50 pound is ok given mine is over 8years old and only now starting to split.
But I only need the outer rubber, everything else is like new.