Impeller change?

[mattias]

I have a mercruiser 350 mag in my 2005 240SD - can I change the impeller when boat is in the water?

 

[Angus]

I doubt it. Unless you’re in 3 ft of water.

 

[GirlyGirl1999]

I have a mercruiser 350 mag in my 2005 240SD - can I change the impeller when boat is in the water?

If you are talking about the raw water impeller in the lower drive, no, if you have a raw water pump in the ER usually located lower left as you look at the engine from bow to stern yes.
Jon

 

[Espos4]

He’s got a Bravo 3.
No pump in the out drive.
Yes, you can change it in the water. You just need to block off the water inlet hose when you disconnect it otherwise you’ll sink the boat.

 

[scoflaw]

^^^^ what he said. Don't need much, stuff a shop rag in it.

 

[tony1b2000]

If you have Bravo 3's, then the pump is in the boat. So it can be done. I have done it several times on my last boat, 350 Sundancer. I HIGHLY suggest you get some (a bag ) of wooden plugs. West marine should have them for short money. Make sure one will fit the inlet hose.
You will get some water in the boat. Not much if you have the plug ready.
Don't stuff the wooden plug in to much. It swells up when it gets wet and is a bear to take out when your ready to reconnect the hose.

 

[GirlyGirl1999]

I yield the balance of my time to the Bravo III folks, +3 you guys rock!

 

[Angus]

Central Ohio and you’re still in the water?

LMFAO

 

[Maggieiscrazy]

I recommend replacing the housing.

 

[tony1b2000]

If the housing is fine (no cracks), bit you see scoring inside, Mercury may make wear plates that go inside. It shrinks the inside pump diameter a bit. Thus, it's a different size impeller.
Thus, in theory. The housing can last much longer. You would just replace 2 plates and the impeller every year or 2. Call Mercury with your engine model number to see if they have that kit.
My 8.1 pumps were scored bad. Any sand kicked up will do it. I made the switch to the plates and never went back.
One plate drops in, the other snaps on. Easy. See attached photo of one of mine

 

[Coz]

View attachment 139988 If the housing is fine (no cracks), bit you see scoring inside, Mercury may make wear plates that go inside. It shrinks the inside pump diameter a bit. Thus, it's a different size impeller.
Thus, in theory. The housing can last much longer. You would just replace 2 plates and the impeller every year or 2. Call Mercury with your engine model number to see if they have that kit.
My 8.1 pumps were scored bad. Any sand kicked up will do it. I made the switch to the plates and never went back.
One plate drops in, the other snaps on. Easy. See attached photo of one of mine

Are you sure it takes a different impeller? One of my pumps has plates, the other does not and I used the same impeller in both with no issues.

 

[tony1b2000]

Hi Coz,

I am 100% sure. If you are installing the inner plate (the one that drops in) that plate is 0.030 thick. Thus the new impeller will be that much shorter.
I am sending you a picture from page 1, bulletin # 90-8m0120899
Of course, these part Numbers refer to my pump. Yours may be different.
I'm not saying your situation won't work, but if you are using the larger impeller with the wear plates, you may damage the impeller or score the wear plates.
When I order the shorter impeller, it comes as a kit with the inner wear plate only. The outer wear plate is a simple swap out. But does not come as a kit.
Replacing the outer wear plate (only) will not affect the impeller size. It's only when you add the Inner wear plate

 

[tony1b2000]

Here is the service / install manual for the shorter impeller. Note: your part number may be different on your model pump.

 

[Coz]

Here is the service / install manual for the shorter impeller. Note: your part number may be different on your model pump.

Thanks. I didn’t know there was an inner plate and don’t recall if my pumps have them or not.

 

[tony1b2000]

The inner plate Is used when the pump gets scored. Because the pump is made of Brass, it can get easily damaged. Thus, Mercury came out with a solution rather than replacing an $800 pump.

 

[Maggieiscrazy]

Any bravo 3 raw water pump I’ve ever seen had a plastic housing. An impeller and housing replacement kit is just over $100.

 

[scoflaw]

Any bravo 3 raw water pump I’ve ever seen had a plastic housing. An impeller and housing replacement kit is just over $100.

That all changed around 2003 when they went to that problematic bronze pump, I liked the plastic pump.

 

[Bill Curtis]

Or the Hardin S/S pump....

Put one on every Bravo engine I have had and zero problems with them.