What to lubricate rubber impeller with?

I have a 4oz tub of 'Starbrite' white Teflon lubricant and am looking for uses, proper and improper, for the stuff. Any thots on its use in/on the Jabsco impeller?
 
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Originally Posted by Boo2
Does [KY] being water-based mean it's not suitable for use in your stern tube ? :eek:



It works OK, but there are special lubes for this purpose.

Ann Summers do one with silicone for "stern tubes"
 
I imagine that any lubricaant isn't going to stay on it long.



My understanding is of it. Just a bit of silicone spray will do fine but you dont need to. It is just to reduce the chance of it sticking when it first turns round.
 
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Just use washing up liquid to help insert the impellor and don't be too bothered as to which way round the vanes lie. As soon as the impellor turns they will lie in the right way, and they are then lubricated by water. Which is what is intended.
 
Just use washing up liquid to help insert the impeller and don't be too bothered as to which way round the vanes lie. As soon as the impeller turns they will lie in the right way, and they are then lubricated by water. Which is what is intended.

I understand from the SpeedSeal website that when destructive overheating and breakup occurs - due to dry running without cooling/lubricant - the significant damage is to the END which bears on the cover plate. That's why, apparently, the latest SpeedSealLife device incorporates a PTFE disc inside the cover plate.

"....Normally the impeller rubs against a static brass cover plate with sea water as lubricant, hence a rapid failure when running dry. The illustration shows the Award Winning Extra Slip Bearing used by Speedseal Life with a PTFE disc placed between the end of the cover recess and the rotating brass disc which is in contact with the impeller...."
 
I understand from the SpeedSeal website that when destructive overheating and breakup occurs - due to dry running without cooling/lubricant - the significant damage is to the END which bears on the cover plate. That's why, apparently, the latest SpeedSealLife device incorporates a PTFE disc inside the cover plate.
So what happens to other end? :confused:
Must say one impeller I fished bit by bit, from wherever pieces of blades got into, had the "ends" still in quite good shape, compared to the center part; it was a bit longish, something like this http://images.gasgoo.com/MiMwMDRfMD...t-flexible-impellers-suitable-water-pumps.jpg
Now I have similar. Might be the reason Speedseal doesn't offer a cover for my engine, despite the pump is popular model.

For lubricants: was told any non-petroleum can do, glicerine, vaseline, butter, lard :) Probably the lanoline too. Not vegetable oils, some can dry hard. Nitrile rubber will withstand petroleum products, but neoprene would not.
 
Those impellers are made in many shapes, quite different; I would not assume any rule. Some pumps even are made for turning both ways.
Was taught to bend it correct way on inserting - it also helps with inserting.
 
So why did the impeller I removed last month have a vane pointing the wrong way?

Exactly!
I changed mine last month, for the first time since I bought the boat in 2010. One vane pointing "wrong way" on the old one being removed so I thought that was incorrect, but when I tried to place-in the new impeller with all vanes facing same way one of them "flipped" back to "wrong" way. So I accepted the seemingly incorrect installation and replaced the cover plate, feeling quite chuffed with myself for having done a long-put-off problem job.
Now I find that I should or should not have used some sort of lubricant.
The engine runs fine, plenty of cooling water coming out the exhaust, bingo!
But now I shall be WORRYING all the time that I have an impeller running-dry and about to break-up.
So much for "care-free" yachting..............

Did I do it the correct way - OR NOT?
 
Exactly!
I changed mine last month, for the first time since I bought the boat in 2010. One vane pointing "wrong way" on the old one being removed so I thought that was incorrect, but when I tried to place-in the new impeller with all vanes facing same way one of them "flipped" back to "wrong" way. So I accepted the seemingly incorrect installation and replaced the cover plate, feeling quite chuffed with myself for having done a long-put-off problem job.
Now I find that I should or should not have used some sort of lubricant.
The engine runs fine, plenty of cooling water coming out the exhaust, bingo!
But now I shall be WORRYING all the time that I have an impeller running-dry and about to break-up.
So much for "care-free" yachting..............

Did I do it the correct way - OR NOT?

on the first revolution the blades will have sorted themselves out. dont worry
 
Johnson pumps list nitrile, neoprene and MC97 compound for flexible impellers.MC97 seems to be a development of neoprene, and is used for water.
My Beta pump impeller for instance is listed as being MC97.
Nitrile is specified for mineral oil resistance, some offered in the same sizes as MC97.
Some of these impellers are interchangeable with Jabsco.
Unless you identify the material as nitrile from the manufacturer's part number , it would be wise IMHO not to use a mineral oil based lubricant.
 
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