Is my Impeller ok?

CapPugwash

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Hello matey forum peeps.

Got an issue on my inboard Mastervolt Whisper generator (not on my barge, not my Saling boat :)). The water flow is heavily restricted and I suspect that the heat exchanger is clogged up with calcium but am checking the easy stuff first. The impeller was changed during a service a few months ago so should be fine. However, I find one blade is facing the opposite way to the others. Is this OK? The internet indicates it may be fine but you know the internet.

Should I bend it back? Water flow is from the bottom.

WhisperImpeller.jpeg
 

Plum

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Hello matey forum peeps.

Got an issue on my inboard Mastervolt Whisper generator (not on my barge, not my Saling boat :)). The water flow is heavily restricted and I suspect that the heat exchanger is clogged up with calcium but am checking the easy stuff first. The impeller was changed during a service a few months ago so should be fine. However, I find one blade is facing the opposite way to the others. Is this OK? The internet indicates it may be fine but you know the internet.

Should I bend it back? Water flow is from the bottom.

View attachment 159791
Not unusual and will sort it's self out on start up.

www.solocoastalsailing.co.uk
 
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penfold

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No visible wear, no cracking, no delamination from the hub; either leave it in place or change and retain as a spare. How much wear is there to the inside of the housing or the face plate? That can make a big difference.
 

peter gibbs

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Thank you
What's the condition of the face plate? If deeply scored work off the ridges with wetted emery paper. Improves water circulation. There should also be a paper gaskit between plate and body, vaselined in place. A small rubber button sits in the centre to further contain water circulation....
Rubber vanes align in motion, no action required.
 

CapPugwash

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What's the condition of the face plate? If deeply scored work off the ridges with wetted emery paper. Improves water circulation. There should also be a paper gaskit between plate and body, vaselined in place. A small rubber button sits in the centre to further contain water circulation....
Rubber vanes align in motion, no action required.
Paper gasket = yes
There is some wear on the plate too.
 

CapPugwash

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Is the pump above or below water line? If above a shaft seal leak can cause it to lose it's prime or suck air in reducing flow.
Does it dribble from behind when running?

I believe it is below the water line, but I will check that.

Yes, water does dribble from behind the pump. I fancy that this is because there is a blockage, in the heat exchanger possibly, causing pressure to build. I plan to run a descaler fluid through it.
 

Stemar

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I believe it is below the water line, but I will check that.

Yes, water does dribble from behind the pump. I fancy that this is because there is a blockage, in the heat exchanger possibly, causing pressure to build. I plan to run a descaler fluid through it.
That means the pump needs have the seals and, probably the bearing replaced. Not a hard DIY job, but if you're paying someone to do it, it might make sense to fit a new pump, as the extra labour for refurbishing may well take you close to the cost of a new pump.
 
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