Author Topic: Impellers - removing them  (Read 8446 times)

Keiron

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Impellers - removing them
« on: April 09 2012, 09:12 »
Does anyone have a finger proof, simple and easy method of removing impellers from their housings?  I struggle and swear like a trooper trying to remove mine from our Volvo D-40 for checking, lubrication and replacement.  it frequently results in bruised knuckles and or finger tips so any tips on how to do this easier would be welcomed.

Cheers

Keiron

Nigel

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Re: Impellers - removing them
« Reply #1 on: April 09 2012, 23:16 »
Does anyone have a finger proof, simple and easy method of removing impellers from their housings?

The Volvo workshop manual says: "Remove carefully [sic] the impeller from the shaft ... with suitable
levers or with long nose pliers
."

However, I've read somewhere (perhaps the instructions that come with the impeller, or was it in Nigel Calder's "Boatowner's Mechanical and Electrical Manual") not to use pliers!

My view is that there is no need to remove it unless you are going to scrap it, so use what you like.

I do however have a tip for replacing them: set a Jubilee Clip to the same diameter as the housing, and slip it over the impeller, making sure the vanes are all pointing the right way. Now offer up the pre-deformed impeller to the housing, and it goes in easily.
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jamescf

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Re: Impellers - removing them
« Reply #2 on: April 10 2012, 15:25 »
Try coating impeller core and grub screw and inside of the pump with silicon (DOW) grease prior to fitting. Ensure the shaft and slot are clean first. When you come to remove it long nose pliers will jiggle it out without damage to the rubber. Check impeller for any splits etc when re-fitting. The grease lubes the rubber.. Great stuff.
I remove mine everytime I leave the yacht and the alternator belt takes seconds with the correct spanners to drop the belt. Keep three correct spanners in the engine bay, Fit a speed seal plate to the raw water pump you can take the cover off with your fingers. It's very easy and prolongs the life of the impeller altenator bearings and drive belt.
By the way use the third spanner to turn your main engine pulley to set at TDC mark this closes the valves and stops any water vapour corroding the valve sealing edges etc. I have been using this method for 6 years on the same engine... same drive belt and only three new impellers fitted in all that time.. My engine run hours only ave 55hrs PA.
Hope this helps
jamescf

Nigel

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Re: Impellers - removing them
« Reply #3 on: April 11 2012, 11:04 »
Try coating impeller core and grub screw and inside of the pump with silicon (DOW) grease prior to fitting...

The kit actually comes with a sachet of this, so it must be a good idea.
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Stuart

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Re: Impellers - removing them
« Reply #4 on: April 11 2012, 13:19 »

By the way use the third spanner to turn your main engine pulley to set at TDC mark this closes the valves and stops any water vapour corroding the valve sealing edges etc. I have been using this method for 6 years on the same engine... same drive belt and only three new impellers fitted in all that time.. My engine run hours only ave 55hrs PA.
Hope this helps


Hi James could you explain a little more about the TDC mark please
Cheers

Stuart

Keiron

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Re: Impellers - removing them
« Reply #5 on: April 23 2012, 11:50 »
I'd read about the needle nose pliers / bent nose pliers but the idea of trying to grip something made of rubber and pulling it with something made to grip metal does not appeal.  I guess fitting some rubber socks might make it less damaging though.

Do like the tip about using the jubilee clip to pre-deform the impeller into shape for installing, might have to look into that one further.

Cheers for all the input

Keiron

Odysseus

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Re: Impellers - removing them
« Reply #6 on: April 23 2012, 12:47 »
2 flat blade screwdrivers 180 degrees apart, one each side of the impeller, lever out at 45 degrees, it comes out ever time.

I get 2 seasons out of an impeller before they start to crack, but this depends on the age of the unit as they do deteriorate over time so go to a high turnover place to buy them.

Look at this youtube  http://www.youtube.com/watch?v=wpBoVRAAZhI

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