Power steering delete or not

[Fireman115]

So I have a 94 rendezvous and the 3.0 that was in it has a cracked block so I got a used 3.0 to go in it. I pulled the old motor out already and the new one has power steering and my old one didn't. What's easier to just take out the power steering or install everything for the power steering? The new motor looks like it has a generator and not an alternator, can I just take the belt off because the belt only runs the power steering pump. The new motor came with the lower unit and out drive too. And this new motor seems like it has a reservoir for antifreeze but that makes no sense. Is that just where water goes? I would have had a shop do it but it wouldn't get done until August and well that's no good. If anyone is near Maine and can help if be very appreciative.

 

[GA_Boater]

You didn't get a 470 to replace a cracked 3.0, did you?

 

[Fireman115]

They are both 3.0 just look different

 

[Scott Danforth]

post a pic of your new motor. something is not right.

power steering on a 3.0 is extremely rare, and a heat exhanged 3.0 is more rare.

my guess is you either have a 3.7 mercruiser motor or an older volvo penta 2.3 liter.

 

[Fireman115]

Here is both, finally figured how to get it to fit for the website

 

[GA_Boater]

You think those are both 3.0?

The one with the heat exchanger is a 470, 3.7L. Intake and exhaust are on opposite sides of the Ford 460 head. 470s use an outboard style alternator stator, that's why there is no alternator like the 3.0.

 

[Fireman115]

I was told it was a 3.0. I'm not a boat guy. I know enough to make myself dangerous. This is all new to me. So if it's a 3.7 does that mean it won't fit or I'll have to make modifications to make it fit? Do I have to change to lower unit and/or outdrive because of gearing? That's why I'm asking for help.

 

[Fireman115]

I hoping to work on it Sunday so any help would be appreciated. Thanks

 

[matt167]

It will work. You'll have to change some stuff over... BUT, you bought a boat anchor. The 470/3.7L was a great idea, and a solid design but it always lacked the R&D that it needed to perfect it.. It's performance levels are equal to the 4.3L, and the 4.3L being a great rock solid engine is why Mercruiser just cancelled the 3.7L production after 1989.. The 3.7L had many problems and weak points, the later motors were better but parts are getting hard to find


If you didn't hear it run/ verify it's charging correctly then it's probably not even worth the time to try to install it

 

[Fireman115]

Ok so here's another question. I'd like to have my boat move a little faster, so if I put like a 4.7 in it do I have to change the transom assembly and the outdrive as well? Or will the 2 I have (3.0 and 3.7) work?

 

[matt167]

If you swap to a V8 the leg will have to change for sure, as gear ratio would not be correct. Actually there is a boat load you have to change although your boat MAY have the placements in the stringers for a V8 or V6 mounting

You would want to get a rotted parts boat if your swapping to a V8, and you will want it to be an Alpha Gen 2 ( 1991 or newer ) so that you don't have to swap the transom assembly

 

[achris]

The drive for both those engines, and the V8s and V6s are all the same. What changes is the internal reduction ratio (the gears sets). For the 2.5 and 3 litre engines, 1.98:1. For the 470 (3.7litre) and some of the V6s, 1.84:1. For other V6s, some 5 litre V8s and the old inline 6, 1.65:1. For most V8s, 1.5:1...

You can run a 1.98:1 with a 470, just change the the prop to one with a pitch of a couple of inches more.

Chris......

 

[Fireman115]

Chris, so if I changed to everything that came with the 470 could I run the 4.7 V6? Because the 470 came with the transom assembly and lower unit.

 

[matt167]

Yes but you will need to figure out mounting the V6, and have all the exhaust parts to a V6... If you use the 470 leg, then you also need to use the 470 transom assembly..

For what it's worth the main confusion you will have is your boat has an Alpha one Gen II being a 1994, and the 470 stuff is MR/ Alpha One Gen 1 or older. IIRC the 3.7L was introduced in 1979

 

[achris]

... IIRC the 3.7L was introduced in 1979

470 introduced 1976. Mercifully discontinued in 1989...

Chris, so if I changed to everything that came with the 470 could I run the 4.7 V6? Because the 470 came with the transom assembly and lower unit.

Your cracked 1994 block and drive (including transom assembly) is what's known as a Gen II. Best advice is to find a post 1992 V6 (4.3L), including exhaust 'Y-pipe', and just put that in place of the cracked engine. If it's a fairly small boat, you may need to find a 1.65 top housing for the drive. But you might get away with the 1.98 drive with a very 'pitchy' prop.

Unload (as in 'sell') the 470 (3.7L) as with it's age, the inherent design problems, and the lack of spares, it'll be a ongoing struggle to keep it running reliably.

That's just what I'd do...

Chris.........

 

[matt167]

Never knew the design started in '76

I have always wanted a 3.7L to put in a non marine application. Swap on an aluminum head, 4bbl, single BBF header and put in a little pre war car..

But yeah offload it, someone will need a spare