Replacing a Mercruiser 470 w/ something else?

[jcole59946]

If I wanted to replace my SeaRay's mercruiser 470 w/ something else, what are the best options? I like the idea of using the Mercruiser 3.0 140 hp I4 but I noticed the gear ratios are much different. The Mercruiser 4.3 V6 has the same gear ratios but the motor mounts look a lot different. Would I get a big performance boost from the Mercruiser 4.3?

Has anyone repowered their Mercruiser 470 something else?

Thanks!

 

[stonyloam]

Re: Replacing a Mercruiser 470 w/ something else?

If I wanted to replace my SeaRay's mercruiser 470 w/ something else, what are the best options?

Thanks!

A different boat. Seriously, I looked into repowering a 470, and for a 20+ year old boat, for me it was just not worth it.

 

[robjen1019]

Re: Replacing a Mercruiser 470 w/ something else?

Agree, I looked into doing a 470 to 4.3 swap and by the time you buy everything you need it would be cheaper and easier to sell one and buy another.

 

[jcole59946]

Re: Replacing a Mercruiser 470 w/ something else?

Thanks for the insight but I prefer to keep my boat.

 

[Bt Doctur]

Re: Replacing a Mercruiser 470 w/ something else?

different exaust pipe, possably a transom housing too,gear ratio will be ok. Have to fiberglass up front stringers to accept the front mounts.

 

[Bondo]

Re: Replacing a Mercruiser 470 w/ something else?

Agree, I looked into doing a 470 to 4.3 swap and by the time you buy everything you need it would be cheaper and easier to sell one and buy another.

Ayuh,.... That's Exactly how it's done if you're in love with the Hull.... Buy Another boat....
Buy a Donor boat,+ Scrap it out for the driveline of your choice....
Hopefully, you'll get All the right pieces, in the right places..

 

[ErieRon]

Re: Replacing a Mercruiser 470 w/ something else?

What's wrong with your 470 ? Just curious...and no sarcastic input needed fellas...

 

[gettin'even]

Re: Replacing a Mercruiser 470 w/ something else?

What's wrong with your 470 Just curious...and no sarcastic input needed fellas...:


WOW. Now THAT'S a "loaded" question..lol!

 

[Rocky_Road]

Re: Replacing a Mercruiser 470 w/ something else?

What's wrong with your 470 ? Just curious...and no sarcastic input needed fellas...

Since I am a 470 owner, I am 'allowed' to post this:

If I decide to change my 470 (it is currently 'broken'), it will be for a 3.0L. My second boat has the 3.0, and I love it!

Happy boating!

 

[natemoore]

Re: Replacing a Mercruiser 470 w/ something else?

What's wrong with your 470 ? Just curious...and no sarcastic input needed fellas...

I'm on the phone right now with the Ministry of Love, and I swear if one of you starts spewing hate speech against any 470, there will be a knock on your door so fast...

Look, the 470 just wasn't as lucky as other engines like the 4.3L V-6. The successful engines had loving engineers to guide them and nurture them. The 470 had abusive, alcoholic engineers who half the time weren't even there. So, let's be a little bit more tolerate, people.

Excuse me while I get the door.

 

[triman]

Re: Replacing a Mercruiser 470 w/ something else?

A friend of mine bought a Bertram 21' a while back with a 470.
Decided to re-engine it and found a 3.8 litre GM-Holden V6 engine for 31 Ozbucks. He;s a very skilled mechanic with a well-equipped workshop so he will be rebuilding the engine and making any new parts over our summer and doing the swap next winter.
The 3.8 is an older Buick engine which GMH had modified extensively and has only just been superseded in our locally produced cars.
Once the process is completed; maybe about 9 months, I'll see if I can get a few photos, assuming I can remember this thread.
However the point is that there are options out there if you are unhappy with the old engine - it just takes a bit of lateral thinking.
Oh yes, and the local hoons have tweaked these engines to get upwards of 500HP - I've recommended to Andy that he doesn't quite go that far as I doubt if the leg could handle it.

 

[jcole59946]

Re: Replacing a Mercruiser 470 w/ something else?

Answer to ErieRon's question, there's nothing wrong w/ my 470 yet. I'm just thinking ahead to the next project and I'd love to put a bigger, faster motor in my boat.

 

[ErieRon]

Re: Replacing a Mercruiser 470 w/ something else?

Gotcha. Was just curious. I've had mine since 1984 and it's been great.

 

[badbird]

Re: Replacing a Mercruiser 470 w/ something else?

well I talked to my maintenance guy that runs a 5000 sq ft machine shop just building boat motors and he was telling me that the 470 was a GREAT motor if properly maintained, the issue is that most people never check simple things and then the engine will fail.. need to check coolant,cap,heat exchanger and it will be fine, hell just like a car if you don't take care of it the thing will be a big POS no matter what engine it has in it

Ron

 

[ErieRon]

Re: Replacing a Mercruiser 470 w/ something else?

Exactly !

 

[stonyloam]

Re: Replacing a Mercruiser 470 w/ something else?

Answer to ErieRon's question, there's nothing wrong w/ my 470 yet. I'm just thinking ahead to the next project and I'd love to put a bigger, faster motor in my boat.

One other thing to consider is that with a V6 or V8 you will be adding 200-300 pounds to the stern of the boat. One advantage of the 470 is that it is relativity light. You could look into putting a 4bbl carb on yours, should get you 20-25 more hp. Good luck!

 

[gettin'even]

Re: Replacing a Mercruiser 470 w/ something else?

Wow! Two positive comments about the 470. History in the making. lol!!!!

 

[badbird]

Re: Replacing a Mercruiser 470 w/ something else?

Wow! Two positive comments about the 470. History in the making. lol!!!!

can we get a third ?

RON

 

[natemoore]

Re: Replacing a Mercruiser 470 w/ something else?

Okay, here's a third.

I found replacement parts for my engine overhaul readily available and not really that expensive since most of the parts were off-the-shelf Ford 460 parts.

I know that's going to chap some hides.

 

[guyaverage]

Re: Replacing a Mercruiser 470 w/ something else?

True that, Nate. If you cant find parts for a 470, you aint trying too hard. Replacement parts practically fall out of the sky for this intentionally-forgotten engine.

Which, on the other hand, is good, because they are frequently needed....

I dont regret at all buying my 470, it has served me quite well. But that being said, it will still be the last one I personally will ever own. Give it a good rebuild using a Merc head gasket, replace the brainless factory charging system with an alternator kit, clean the heat exchanger every year with muriatic acid, replace the water pump seals every few years, and make sure you either have, or convert to, the later style aluminum exhaust manifold, and you will end up with a torquey, fuel sipping, snarly beast of an engine that will last....for a while, at least.........probably......just make sure you trade it or sell it before the next wave of the-same-old-problems start over again 3-4 seasons later.