Impeller

Joined
Apr 2, 2005
Messages
27
I'm running an 2000 Mercruiser V8 with a Bravo III sterndrive. I bought the boat last season and I do not know if the impeller has ever been changed. Where is it located, can it be reached from the engine compartment and the boat in the water and what level of difficulty is it to change?
 

rodbolt

Supreme Mariner
Joined
Sep 1, 2003
Messages
20,066
Re: Impeller

its usually belt driven on the stbd side lower front of the motor. if its below the water line you willneed a 1 1/4 plug to capoff the seawater in line when you remove it from the pump. carefully check the plastic body and the end plates.
 

Don S

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Aug 31, 2004
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Re: Impeller

It's the only raw water impeller on Bravo drives.
 

TilliamWe

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Dec 21, 2004
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Re: Impeller

what level of difficulty is it to change?
If you have any mechanical ability, it's not hard at all. It usually is hard to reach, though. All depends on the shape of your boat/bilge. It can be a little difficult to put it all back together, sometime a second person to hold the housing is nice (my wife is very good at that!). :) <br />I would recommend doing this service before you run the engine. The exhaust manifold will be right where you are working, and they can be a little warm. Of course, if you wait until the impeller is ruined, then the motor overheats, and that manifold is HOT! Ask me how I know! :eek:
 
Joined
Apr 2, 2005
Messages
27
Re: Impeller

Thanks, I will see if I can locate it and try to do myself. I've been searching for a picture of where it is located, I have a manual but the diagrams / pictures aren't that good. any suggestions?
 

bigbrownbuku

Master Chief Petty Officer
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Sep 17, 2004
Messages
885
Re: Impeller

it will be belt driven of the crack pulley. if it has never been serviced it is going to need doing.<br />it should have 2 hoses coming from its back around 2" od. its held together with 6 bolts all facing aft. i just serviced one yesterday and now my left kidney has a throttle body looking dent in it.
 

TilliamWe

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Dec 21, 2004
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Re: Impeller

In case I wasn't clear, when I say it's not hard to do, I am talking about unbolting the pump from the motor first & holding it in your hands when disassembling/reassembling.<br />If you have a carbed engine, it's more difficult, cause the fuel pump will be attached, but if you have F.I., it's 1) remove two big hoses, plug the one, so water doesn't run in. 2) Loosen serpentine belt at the tensioner pulley (easy). 3) Remove two bolts from braket to block. 4) lift pump assy out. 5) Unbolt the 6 bolts thru the case. 7) Inspect the case & slide the impeller off the shaft (easy). 8) slide new impeller on. 9) reassemble pump, (this is where the second set of hands comes in handy) reinstall.
 

TilliamWe

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Dec 21, 2004
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6,579
Re: Impeller

As far as finding it on your engine, go out & look at the motor. As you are facing the motor, it should be to your left and down low. If this helps, if you had a mech fuel pump mounted to the block, it would stick out & hit this water pump assembly.
 

Don S

Honorary Moderator Emeritus
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Aug 31, 2004
Messages
62,321
Re: Impeller

I could probably find a picture of the pump for you, What engine do you have? Is it a 5.7 or a 7.4L, is it carbed or EFI, raw water or fresh water cooled? <br />Do you have the Mercruiser manual?
 

1Moredrift

Seaman Apprentice
Joined
Feb 2, 2004
Messages
36
Re: Impeller

Tilliamwe,<br /><br />Thanks for that step by step run down. Are there any seals or gaskets that should be replaced? <br /><br />Do you need a sealant like permatex for this job>
 

TilliamWe

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Dec 21, 2004
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Re: Impeller

no seals or gaskets to replace on my pump. There is a "wear plate" in between the plastic housing and the pulley part of the pump. It may have "grooves" in it. You can "flip it over" and you don't need to replace it. No sealant required at all!<br />I say all of this, but a Mercruiser service manual probably does an even better job of explaning it.
 

1Moredrift

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Feb 2, 2004
Messages
36
Re: Impeller

I have a manual at home, but I am trying to come up with my shopping list for getting the boat ready. I'll have ther service manual real close as I tackle my projects in a few weeks. Thanks again!
 
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