Bellows Batteries and other things that age

rider · 03-07-2010, 08:31 PM

4.3L engines are fine with alpha's. As for impeller change, it should be done every year. If you had a Bravo and changing the impeller was a pain, its not Merc's fault. Just a poor boat design. I've seen Baja's where the impeller was behind a stringer and removing the impeller was impossible, I had to lift the engine up with a hoist to swap out the impeller. NoBozo is right on the money with HP and the cut off for the drives.

Dave R · 03-07-2010, 09:04 PM

Quote:

Originally Posted by rider

If you had a Bravo and changing the impeller was a pain, its not Merc's fault. Just a poor boat design.

Agreed, but with an Alpha you know it's ALWAYS going to be easy to get access regardless of boat design and it's relatively easy work to do. Plus, you don't have climb in and out of the boat to do it.

rick35 · 03-07-2010, 09:56 PM

Just received the Seloc Mercruiser manual for my 2008 3.0L. I've been thinking about how much work it would be to inspect/replace the impeller. Looks more complicated than I expected. I'm concerned about taking the lower unit apart. Anyone tried this? Any recommendations?

jrc · 03-08-2010, 08:23 PM

Given a "new to me" used boat without solid repair records, I would change the impeller. I had one fail at 375 hours, almost four full seasons and it stranded me in the middle of the Broads.

Batteries depends on age and how you use the boat. If a dead battery could ruin a day of boating or strand you, then I'd change after my fourth winter. If you have several batteries, be more daring.

I never owned a boat long enough to have bellows problems. Six years seems like a pretty short life in fresh water.

As for alphas never heard any complaints. Bravo 3's on the hand have a big issue with corrosion even in freshwater. Make sure you check it well and put magnesium anodes on in place of the stock aluminums. Plus if you break a prop on a Bravo 3, it will cost you around $1200 for a new set.

Chaos · 03-08-2010, 10:40 PM

JRC,
You recommended Magnesium for the anodes. Is there that much of a difference over Zinc? I realize that Magnesium is further away from Aluminum on the Galvanic chart, but I don't have any concept of the value of one over the other. Is there a cost difference?

jrc · 03-09-2010, 06:01 AM

Mercury ships the drives with aluminum anodes that are suppossed to be good enough for salt or fresh. But if you complain about all the paint corroding off your Bravo 3, they will tell you that magnesium anodes are required for fresh water and zinc anodes for salt water. My first B3 lost a bunch of paint in two seasons in the very clean water on a mooring on the broards.

rider · 03-09-2010, 05:03 PM

If you don't know what your doing, you could have some issues. From refilling the drive improperly to making sure the shift fork is alighned. You could end up with more headaches than its worth. Impellers should be changed every year. If your going to inspect it, might as well replace it at that point (Its only $50). For what they cost and work involved changing them its worth it. If an impeller breaks apart, all of the veins need to be accounted for or else your in for problems in the future (overheating, water injection issues, and problems).

03-07-2010, 09:56 PM	#3
rick35 Senior Member Join Date: Mar 2008 Location: Bear Island/Merrimack Posts: 807 Thanks: 58 Thanked 203 Times in 130 Posts	Good timing... Just received the Seloc Mercruiser manual for my 2008 3.0L. I've been thinking about how much work it would be to inspect/replace the impeller. Looks more complicated than I expected. I'm concerned about taking the lower unit apart. Anyone tried this? Any recommendations?

03-08-2010, 10:40 PM	#5
Chaos Senior Member Join Date: Apr 2009 Location: Danville, NH and West Alton Marina Posts: 134 Thanks: 111 Thanked 32 Times in 20 Posts	magnesium vs. zinc JRC, You recommended Magnesium for the anodes. Is there that much of a difference over Zinc? I realize that Magnesium is further away from Aluminum on the Galvanic chart, but I don't have any concept of the value of one over the other. Is there a cost difference?

03-09-2010, 05:03 PM	#7
rider Senior Member Join Date: Jul 2009 Posts: 51 Thanks: 2 Thanked 5 Times in 5 Posts	leave it to the pros..... If you don't know what your doing, you could have some issues. From refilling the drive improperly to making sure the shift fork is alighned. You could end up with more headaches than its worth. Impellers should be changed every year. If your going to inspect it, might as well replace it at that point (Its only $50). For what they cost and work involved changing them its worth it. If an impeller breaks apart, all of the veins need to be accounted for or else your in for problems in the future (overheating, water injection issues, and problems).

03-07-2010, 08:31 PM	#1
rider Senior Member Join Date: Jul 2009 Posts: 51 Thanks: 2 Thanked 5 Times in 5 Posts	4.3L engines are fine with alpha's. As for impeller change, it should be done every year. If you had a Bravo and changing the impeller was a pain, its not Merc's fault. Just a poor boat design. I've seen Baja's where the impeller was behind a stringer and removing the impeller was impossible, I had to lift the engine up with a hoist to swap out the impeller. NoBozo is right on the money with HP and the cut off for the drives.

03-08-2010, 08:23 PM	#4
jrc Senior Member Join Date: Apr 2004 Location: NH Posts: 2,689 Thanks: 33 Thanked 439 Times in 249 Posts	Given a "new to me" used boat without solid repair records, I would change the impeller. I had one fail at 375 hours, almost four full seasons and it stranded me in the middle of the Broads. Batteries depends on age and how you use the boat. If a dead battery could ruin a day of boating or strand you, then I'd change after my fourth winter. If you have several batteries, be more daring. I never owned a boat long enough to have bellows problems. Six years seems like a pretty short life in fresh water. As for alphas never heard any complaints. Bravo 3's on the hand have a big issue with corrosion even in freshwater. Make sure you check it well and put magnesium anodes on in place of the stock aluminums. Plus if you break a prop on a Bravo 3, it will cost you around $1200 for a new set.

03-09-2010, 06:01 AM	#6
jrc Senior Member Join Date: Apr 2004 Location: NH Posts: 2,689 Thanks: 33 Thanked 439 Times in 249 Posts	Mercury ships the drives with aluminum anodes that are suppossed to be good enough for salt or fresh. But if you complain about all the paint corroding off your Bravo 3, they will tell you that magnesium anodes are required for fresh water and zinc anodes for salt water. My first B3 lost a bunch of paint in two seasons in the very clean water on a mooring on the broards.