How often to replace Bravo 3 impeller, very difficult job

Scott Danforth

Grumpy Vintage Moderator still playing with boats
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with a bucket above the pump...gravity is doing the work... the pump impeller could have one vane and move water in that scenario

besides not winterizing properly, your "mechanic" was blowing smoke up your arse
 

Lou C

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Nov 10, 2002
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If you have a raw water cooled engine and that's how he winterized it, I would:
make sure you have an invoice indicating what was done if there is a problem in the spring
if you can, take a sample from each block drain to make sure there is really AF in the engine!

it has been discussed many many times, the danger of using the suck AF up the drive method, if the engine is not drained first or the 'stat not removed first. If he did either, then OK, if he did neither, then I'd check the drains.

I think for the Bravo or Volvo pumps to prime, its best to have a pressurized flow, gravity may or may not be enough, if you can jack the front of the boat down as far as you can get it that helps, I would add a pump to a winterizing tank if I used one (on a closed cooled engine only, that is).
 

tpenfield

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How much 'suction' is too subjective for a mechanic or anyone else to say. Keep on your schedule of impeller changes.
 

thumpar

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I wouldn't judge just on suction. The pump can work great until it doesn't. If the fins get cracked it may only take one to fail and the whole thing falls apart. When I first got mine it worked great and then it didn't. When I took it apart all the fins were missing and in the hose. It all went at once.
 

DouglasW

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Apr 20, 2018
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I haven't had my boat long enough to do the pump replacement yet. The previous owner said he replaced the impeller 2 months before the sale and did it himself. The bolts looked like they had been disturbed recently and I believed him. He did not look like a mechanic type so I assumed it wasn't that hard. Maybe it is. I do check the temp gauge often though.
 

KD4UPL

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Feb 13, 2010
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Good news. I got in touch with the mechanic who serviced this boat for the previous owner. He said he changed the impeller in 2016 and the boat only has about another 35 hours on it since then. 30 of those I put on it this year.
I think I'll go at least 1 more year on this impeller.
 

rick3452

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Oct 26, 2010
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282
Ive done it probably 5 times in eight years. Next time I'm buying a Johnson Crank Mounted Water Pump I cant take the bruises and blood any longer. I have just enough clearance to make the change.
 

HT32BSX115

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Dec 8, 2005
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10,083
There was no other pump. The guy had a bucket of antifreeze sitting on the swim platform with a hose connected to the muffs on the outdrive.

I have winterized my Closed-Cooled Bravo this way.

But to do that you MUST fill the hose first so it will readily siphon, then with a "Cat-Box" under the drive, after the flow starts (and right before the bucket is empty) you can move the suction end of the hose from the bucket to the "Cat-Box" for continuous flow (of your water/AF mix)

However, like I said in a different thread, NEVER DO THIS WITH OPEN COOLING or you are just asking for a cracked block!!!


Good news. I got in touch with the mechanic who serviced this boat for the previous owner. He said he changed the impeller in 2016 and the boat only has about another 35 hours on it since then. 30 of those I put on it this year.
I think I'll go at least 1 more year on this impeller.
I think 2 or 3 years is ok in fresh water too.

I also bought and installed a Hardin Marine stainless steel raw water pump housing after mine cracked.

I am sure it's because I tightened the bolts too tight!! Not gonna happen now though no matter how tight they are!



73/Rick
 
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