how long do your impellors last for?

[blueglass]

one of my impellors is a pain to get to but religiously renew every season even though they look OK. trouble is you really need to remove to inspect thorougly and having done that you may as well replace. Am I being over cautious? How often do you this? I'm thinking maybe every other season would do. I habituallly cruise at displacement speeds at least 80% of the time so they have an easy life. what do you think?

 

[nedmin]

Check every year but dont change every year,I bend the vanes over and if there not cracked, put back.Never had a prob. doing this.Smear well with silicon grease.

 

[Richard10002]

Fitted one in August last year and it lasted until a plastic bag or something blocked the intake - heard a change in the engine noise, (deeper and boomier), and immediately checked for no water at the exhaust and turned off.

Sure enough the impellor had failed, and we found the missing bits just before the heat exchanger pipes.

One thought I had was that if one or two of the pipes got blocked, it wouldnt be the end of the world as there are lots of them.

I tend to let sleeping dogs lie, but will probably change every 2 years if it doesnt fail.

 

[DAKA]

I believe you will find volvo impellers are made by jabsco.

jabsco make two types

a)Nitrial/nitrate ?

b)neoprene

Volvo only use nitrial/nitrate.

Nitrate is much harder and wears quicker and distorts quicker.
you should replace these every year.

neoprene are softer and will not wear, they could easily last 3 seasons.

Nitrile/nitrate withstand a higher temperature before damage is done but bearing in mind they only pump cold seawater i ask myself why nitrate are used, in theory if you run them dry they may last an extra 10 seconds longer than the neoprene ones.

Neoprene are cheaper.

Why dont you try neopream for two seasons in the awkward side ?

I expect you will soon convert both to neoprene, they are also significantly easier to fit and remove .

 

[blueglass]

have jabsco impellors fitted currently but not sure which type - will check that out though -thanks

 

[Petrolia]

Interesting question.

Surprisingly I've not heard discussion on potential life span before although I've wondered myself having had one fail at sea recently.

You are right they are Jabsco but I didn't realise there were two kinds. Wasn't given the option when I last purchased spares.

If the nitrile is harder I can visualise it distorting more easily but why would it wear faster ?

Also when mine failed the bits were safely in the filter. Isn't this the way it should be ?

So does Volvo give any idea of life span ? Daft question I suppose.

 

[blueglass]

nedmin - so how many seasons before they need replacement?

 

[DAKA]

[ QUOTE ]
.

If the nitrile is harder I can visualise it distorting more easily but why would it wear faster ?

Also when mine failed the bits were safely in the filter. Isn't this the way it should be ?



[/ QUOTE ]

As the harder impeller is less flexible it distorts and cracks are formed.

(I am only talking about pleasure use)
Technically impellers never wear out, they crack and fall to bits.

if you ran an impeller 12 hours a day for a year then the impeller would wear and nitrial would last longer.

I ran my last boat on neoprene and saw no signs of wear after 4 seasons(checked every year).

 

[nedmin]

As said I check annually for cracks by flexing the blades I suppose about the longest time one lasted without cracking is about 3 seasons.