Be Wary (Maybe) of Stay Cool Pumps Impellers

[a64pilot]

Originally Posted by NoTies

Obviously you missed the bit about it being a plasticiser. Still, it appears arrogance rather than facts are what counts when it comes to the pilot.

I don’t understand how I’m being arrogant, nor have I seen any “Facts”
But welcome them, cause I’d like to know what happened, I don’t enjoy changing impellers and don’t like them failing on me. So far other than speculation, Gord has shown the only thing that I would consider a fact, that this type of failure is indicative of a blockage of water flow.
The other fact I guess is Jim noticing that the diameter of the hub is larger, whether that is a contributing fact to failure is conjecture.

[a64pilot]

Originally Posted by Simi 60

What's all that other brown gunge?
Almost looks like incompatable coolants?

If memory is correct it’s a salt crust, and staining of the bronze. The salt build up may be due to the restricted water flow and maybe the raw water flow getting hot enough to deposit salt, which if it was, ought to be self cleaning with higher water flow and cooler water.
What your looking at is the heat exchanger cap. So no coolant is ever present here, just raw water.
When I bought the boat it had Dexcool in it, which is correct IAW Yanmar, but had some rust, so I installed the Prestone flush kit and flushed it repeatedly until just fresh water came out, then used just plain ole Green Prestone.
Then Dec. of last year I flushed it again throughly and used Zerex HOAT coolant.

While I have never had any trouble with Dexcool, apparently many others have so I decided to avoid it. I don’t need or want long life coolant, it was brought to my attention that due to the possibility of salt water contamination, that we should flush and refill more often and don’t need long life coolant.

[wsmurdoch]

I have always lubricated my rubber impellers with salad oil, but this thread caused me to take a look around, and it looks like glycerin is the recommended lubricant for Johnson impellers. (p10)

https://www.spxflow.com/en/assets/pd...n_JP%20web.pdf

Bill

[a64pilot]

Glycerine is very water soluble and therefore is washed off almost instantly. Oils not so much, and some oils may attack some plastics / rubber. Probably not salad oil though.
It used to be a large part of antifreezes and I want to think still is in fire sprinkler systems as it’s not toxic like ethylene glycol is, but I may be remembering that wrong.
Glycerine is non toxic, cheap and washes off pretty much instantly.

Glycerine is used in a lot of liquid filled gauges too.

[Compass790]

I use silicone grease to lube impeller as its ok for o-rings but doubt it has any real effect on life long term, cant imagine anything staying on those blades for a long. But yes for the 1st start good idea.
Used salad oil before got silicone grease or the glycerine if it came with it

[Enyar]

So what's the verdict, do we like the staycool parts?

[Sailmonkey]

Originally Posted by Enyar

So what's the verdict, do we like the staycool parts?

I won’t order them anymore for my oberdorfer 202m-15 pump. They only last 50 or fewer hours, where the OE impellers easily exceed 300 hours.

[Dave9111]

Originally Posted by Enyar

So what's the verdict, do we like the staycool parts?

NO! AVOID!



As I said earlier in this thread, I bought two of them for an Atomic 4 sailboat engine and they were too flexibile (my opinion) and did not properly pump water. The volume was noticeably low. They did pump "some" water but the volume was much less than expected. I changed out the new Staycool part with a pump impeller supplied by Moyer Marine and presto - everything works. I have had the same Moyer Marine impeller in place now for 3 years and it still works fine.

Its a sailboat, so I don't put that many hours on the engine per year. Maybe 50 per year.



Dave

[rslifkin]

So far the one I put in my generator is doing fine, but only has about 3 hours on it. We'll see how it holds up, as the OE impeller is discontinued and there aren't a lot of choices from what I can find.