Mercruiser Alpha 1 VS. Volvo Penta SX

rkilpa

Petty Officer 3rd Class
Joined
Oct 16, 2009
Messages
86
I have owned a Volvo Penta 4.3 GL with an SX outdrive for 20 years. I am comfortable servicing both.

I am considering a boat with a Mercruiser 5.0 and an Alpha 1 outdrive. The 5.0 looks easier to service with the top mounted oil filter, so I'm not really concerned about the motor. My concern is the impeller in the outdrive. My VP has the fresh water pump and impeller mounted to the front of the engine and it's a fairly easy replacement job. WIth the need to remove the upper and lower unit to access the impeller, it sounds like a more difficult job with more risk of error.

For those of you that have serviced both, what would I be getting myself into?
 

achris

More fish than mountain goat
Joined
May 19, 2004
Messages
27,468
Mercruisers are a lot easier to do. Parts are also seriously cheaper... In my signature you'll see a link to 'My Videos'. Have a look at those. I have done service videos on drive removal/replacement and water pump servicing.... Make your own choice once you see how easy it is.

And the 5 litre and 5.7 litre V8s are just the same as the 4.3 V6, but with a couple of extra spark plugs ;-)... Most other things are the same...

Chris......
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
Staff member
Joined
Jul 23, 2011
Messages
50,292
Chris, I have changed both the alpha impeller and the front mounted VP impeller. its literally 3 minutes to have the impeller changed on my boat and 2 of those are unsnapping the cover and gettign tools. its about half an hour for those of us that dont do the alpha often to drop the leg. I would have to argue the easier to do one there.

the good news is that the service period is far enough apart.

bellows are about the same.

both the SX and A1G2 have gimble bearings, etc so that service is the same

any motor can have a remote mounted oil filter.

mercruiser parts are certainly less expensive
 

camalot

Petty Officer 2nd Class
Joined
Jul 24, 2012
Messages
144
The Penta is so much easier............ quicker and cheaper than the mercruiser. The price of the impeller kits are very close but with the Mercruiser you will have to add the cost of gear oil unless your doing it when your servicing anyway. Mercruiser Alpha is clunky when shifting Penta SX is smooth like a B3
 

achris

More fish than mountain goat
Joined
May 19, 2004
Messages
27,468
Alpha One Gen II has a 3 year/300 hour oil change and impeller service interval...

Chris....
 
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