Converting from outboard to inboard

[KennyBradley]

Hi,

I have been offered a very nice looking Four Winns 257 Quest for next to nothing. She has fallen off her trailer and has some cosmetic damage which looks fairly east to put right.

Problem is she has twin 200hp outboards, to reduce running costs I need to sell the 2 outboards and fit twin diesel inboards with sterndrives. I’ve done a few searches on this forum and found plenty of info on converting from inboard to outboard but nothing on converting outboards to inboards.

There are two problems:

The large grp moulded stringers run all the way to the transom and are quite high because they support the deck. I would need to lower them near transom to make room for the inboards.

The Transom is shaped to mount the outboards and there may not be enough room to mount inboards up close to the transom. Some of it may have to be cut away and a flat transom fitted.

I realise this is no small task and I wouldn’t be considering it if I wasn’t getting such a great deal on the boat. Is it feasible to make these modifications without compromising the strength of the hull? Any advice would be much appreciated. Are there any helpful websites out there that may be able to help?

Cheers Kenny

[marshmat]

What model are the 200hps? If they're reasonably recent vintage you may find the cost of the diesel conversion to be more than the fuel savings over the life of the boat. It's worth checking.

Stringer-wise, every boat is different. You may have to move/cut floors, but I would advise against tampering with stringers as they tend to be for hull support. Your transom modifications will be elaborate, but are doable.

In a 25-footer, twin diesels might be a bit of a pain to fit. Perhaps look at a single diesel sterndrive? But I do believe the conversion is feasible, although difficult.

[KennyBradley]

Thanks for the reply.

I think I'll have to think about it. A single diesel could be fitted without modifying stringers and may be the way forward. I just like having the back up of two engines.

Cheers

[Triance]

Hi Kenny
did you buy the 257 QUEST ,and cheep was it ???

Reards Kevin

[KennyBradley]

No Kevin,

In the time I was pondering the conversion problem someone else got there before me. Very disappointed.

Cheers Kenny