Replacing 4.3L Alpha One Water Pump Impeller?

SEMIJim · 06-24-2013, 08:04 PM

Hi,

Has anybody here ever tried this: How to Replace an Impeller on a MerCruiser Alpha One.

Seems pretty darn straight-forward. Doing it that way: Draining/refilling the gear oil isn't necessary.

Only thing I'm wondering about is this bit:

Quote:

2. Mark the position of the trim tab. Remove the Allen screw that holds the trim tab in place and remove the trim tab.

Picturing our boat's outdrive, in my mind, I cannot imagine what they're talking about.

Thoughts? Experiences?

Thanks,
Jim

***ColoradoDiablo*** · 06-24-2013, 08:23 PM

Never really had much faith in EHOW. Your gonna loose drive oil! No way around it.
Here is the proper way Jim

Lots of info to boot!

SEMIJim · 06-25-2013, 02:21 AM

Quote:

Originally Posted by ColoradoDiablo

Never really had much faith in EHOW. Your gonna loose drive oil! No way around it.

Thing is: When our boat was repaired, first season we had her, a mechanic hadn't gotten something Quite Right when he put the outdrive back together, and, IIRC, the shifter wouldn't shift in one direction or another. The service manager knew from the symptoms, right off, what was wrong. He had her hauled back out, dropped in an empty rack so the outdrive was about where it'd be if the boat was trailered. got some tools, carefully dropped the bottom, fixed it (it was a linkage that wasn't in the Right Place), and put it back together.

Not a drop of fluid anywhere.

So if the water pump can really be reached by just dropping the bottom of the lower unit...?

Quote:

Originally Posted by ColoradoDiablo

Here is the proper way Jim

Lots of info to boot!

Thanks for the link! Bookmarked!

I think I'll call that place and ask them how much they'd charge to replace the impeller, and when they could get to it.

Jim

***ColoradoDiablo*** · 06-25-2013, 03:42 PM

I've done it at the lake and it ain't no fun.

All you got to do is make sure that it is in forward position when you reinstall the lower.
Didn't loose a lot of gear oil , but did loose some. Maybe that drive had a seal leaking a little , I don't know.
I'd be changing the fluid if I went that far anyway.

JMO

Smokymance · 10-03-2014, 03:01 AM

How often are you guys changing your drive water impeller ? I see many talks staying yearly or every two ears.

***mikeyt*** · 10-03-2014, 03:19 AM

Every 3-5 yrs. If you spend a lot of time in shallow sandy lakes or put a lot of hours on the boat each year then maybe every 2-3 yrs. Anything more often than that is over-kill.

Smokymance · 10-03-2014, 01:10 PM

Perfect thanks, Im assuming no way to tell if its going bad...maybe overheating issues at low RPM? ill have to find out when mine was replaced last.

Andy b · 10-03-2014, 03:45 PM

Quote:

Originally Posted by Smokymance

Im assuming no way to tell if its going bad....

A small modification I do is cut the hose from the transom shield to the circulating pump and insert a piece of clear tube.
I've done it on all my boats, (must get around to doing it on this one!)

As soon as you fire the motor up you can then see water flowing through the pipe