Repower My Formula

sneekinfreek · 12-14-2006, 09:07 AM

I have asked many questions on repowering but have one more ..? Could any one tell me if I can do a simple swap from my 91 7.4volvo penta Litre to an newer 8.1 litre volvo penta without having to change alot of stuff. The outdrive is a 91 duo prop and my boat is a 91 formula 223.

jeff32 · 12-14-2006, 01:21 PM

You need a pro opinion... I don't know much about Volvos... same for most of the other average boater like me on the board I would guess...

But I'm still curious to know the answer!

handfulz28 · 12-14-2006, 03:02 PM

I'd post this question in the General Tech forum. There's probably a bunch of people that would have more direct experience, even though most talk about Mercruiser.
The hardware would probably bolt up, but I have no clue if any electronics would've changed.
Thanks,
Michael

sneekinfreek · 12-14-2006, 08:45 PM

thanks guys i have had very little on this subject and as i have seen so have others. i really do love this motor and outdrive. i would love to see a bigger motor push it along

offthefront · 12-14-2006, 09:53 PM

Or ... I have 2 fresh 502 Mags .... I bet you can install the Bell housing off your motors ....but as said post in General Tech section .... Let me know if your interested in the motors ....m

Ted G · 12-14-2006, 10:09 PM

The 7.4 and the 8.1 engines are different generations so the accessories will not bolt up. You basically need a dressed 8.1 to do it. The good news is that the mounts and bellhousing match up so you are o.k. there. Dave M. here on the board did this swap with his 24 Superboat and it came out nice-he can probably give you some pointers and needs to get it done right. If you can get a take out engine complete the job should be fairly straightforward.

offthefront · 12-14-2006, 10:46 PM

Quote:

Originally Posted by insptech

The 7.4 and the 8.1 engines are different generations so the accessories will not bolt up. You basically need a dressed 8.1 to do it. The good news is that the mounts and bellhousing match up so you are o.k. there. Dave M. here on the board did this swap with his 24 Superboat and it came out nice-he can probably give you some pointers and needs to get it done right. If you can get a take out engine complete the job should be fairly straightforward.

So the 502's ( they are complete) would work ?

There was someone on OSO that was selling low (10-30hr) 496's .... Some of them....if not all were Volvo's and seemed it was a good swap for the mercs

sneekinfreek · 12-15-2006, 07:44 PM

I am really leaning towards the 496 . I did find a couple of them in the classified section . they are complete as far as I can tell. Thanks alot for the info offthefront . I just need one and I am not sure if I will do it real soon . This is great input and I really do appreciate all you guys giving me the chance to ask for info.

Ted G · 12-15-2006, 08:16 PM

Yes 502's and 7.4 (454's) are the same engine in each generation. Virtually all the bolt ons are the same. If you can get a good take out with all the accessories on it it is the easiest swap since everything will match up and all the wiring is loomed properly.

offthefront · 12-15-2006, 08:42 PM

Quote:

Originally Posted by sneekinfreek

I am really leaning towards the 496 . I did find a couple of them in the classified section . they are complete as far as I can tell. Thanks alot for the info offthefront . I just need one and I am not sure if I will do it real soon . This is great input and I really do appreciate all you guys giving me the chance to ask for info.

you cant go wrong with the 496 ...turn key ...