Which engine?-gctid344028

[welshswampy]

I have a 1988 24ft Bayliner Trophy hard top with a 5.7l motor and a cobra outdrive

I want to repower with a diesel

Has anyone else done the same sort of thing and if so what size diesel engine did you use

I can get my hands on a ford 2.4l TD that came out of a transit van, but this is only about 70hp, would this push the boat to over 20 knots?

I'm guessing that the boat weighs around 3 ton?

Any help or suggestions most welcome

Also if anyone has an engine etc thats for sale here in the UK, please contact me

Regards Nick

[ksanders]

In a word no a 70 HP engine will not push your 24' bayliner trophy over 20 knots. You'll need about the same HP in a diesel as you would need in a gas engine, something over 250HP would be a pretty good guess.

Marinizing a diesel engine and adapting it to an outdrive would be quite the challenging undertaking.

If you want to repower there are lots of options in marine engines.

[2850Bounty]

Perhaps there is something that would work with the OMC, but I'm not aware of any.

Merc on the other hand, did offer a diesel. This would be an acceptible conversion.

Volvo Penta, on another hand (and in the AQ series), used the industry standard Borg Warner pattern flywheel cover and the PDS adapter housing.

This means that most any diesel that is Borg Warner capable, could be adapted and re-fit to an AQ series drive.

The Borg Warner components make this rather simple and easy.

Exhaust may require some special engineering.

Both Merc and Volvo Penta will lead you to one of the twin counter rotation propeller drives.

These would be the Merc BIII and/or the Volvo Penta Duo Prop.

.

[Guest]

Here's a $30k solution for a $8000 boat.

http://www.yanmarmarine.com/theme/ya...K3047B_web.pdf

I guess my point is that it doesn't seem to make too much sense to spend the money for this conversion when the investment in the boat will not be recovered when you go to sell.

[ksanders]

Nehalennia wrote:
Here's a $30k solution for a $8000 boat.

http://www.yanmarmarine.com/theme/ya...K3047B_web.pdf

I guess my point is that it doesn't seem to make too much sense to spend the money for this conversion when the investment in the boat will not be recovered when you go to sell.

You know, not much of what we do with our boating $$ makes any financial sense. but then again thats why they call it boating.

I dropped $25K in a new power package on our 2859 only to sell the boat 2 years later. Yes, I got a premium price for the boat, but I lost big $$ in the total deal.

Was it worth it? Of course it was. I had a great time and supported our economy! :surr

[Guest]

There are smaller cheaper Packages available than that which would be more suited for a 24'

Volvo D3 or D4 I would probably go with the D4 225 but I am VERY VERY BIAS

http://www.volvopenta.com/VOLVOPENTA...gineRange.aspx

Attached files [img]/media/kunena/attachments/vb/646690=23804-2624.jpg[/img] [img]/media/kunena/attachments/vb/646690=23805-2626.jpg[/img]

[2850Bounty]

Your drive shaft bellows have this to say to you: "Ouch.... please lower the drive... you're stretching my belly!"

[Guest]

LOL hit hadnt even hit the water yet at that point, it was still on blocks at the installers yard.:hammer

[706jim]

Nehalennia wrote:
Here's a $30k solution for a $8000 boat.

http://www.yanmarmarine.com/theme/ya...K3047B_web.pdf

I guess my point is that it doesn't seem to make too much sense to spend the money for this conversion when the investment in the boat will not be recovered when you go to sell.

I was going to mention this same engine. It sure looks sweet. But once again, putting this much money into an old boat pretty much ties you to it unless you take an enormous financial hit on resale.

[welshswampy]

Thanks to all who replied

I wouldnt/couldnt install a new engine due to the price

I'm hoping I can pick up a diesel mercruiser and bravo set-up second hand for around 4 k

This wouldn't put me in too deep moneywise and I'll keep the boat for a few more yrs

I only asked about the ford engine because over here they are 2 a penny, and the marinising kits are available

The fact that it would be a diesel will increase the value a fair bit over here due to petrol costs etc, so it would still be saleable

[Guest]

I m not familiar with the cobra transom hole but is it larger than the bravo? Could mean a transom rebuild which is probably due on an 88 anyway.

[welshswampy]

Yes, I think the cobra transom is smaller than the bravo. however, I've seen an adaptor transom plate which would overcome this problem

The plate is oversize so would cover the larger hole with ease

[Guest]

I don't understand Welshswampy's comment on fuel costs as Petrol in the U.K. is cheaper than Diesel !!!!

Unless you use Red Diesel [ low tax Agri / Ind ] which has been illegal to use in Rec boats since 06.

The Customs & Excise in the U.K. have more powers than the Police and the fines would be more than the boat is worth !!!

If you convert and intend to keep the boat for about 30 years you'd just about break even, some chance of the motor lasting that long !!!!!

I'll run my 5.0 SBC until it dies and then replace with a 5.7 vortec, cheaper in the long run.

Just my 2 cents all the best Joe

[2850Bounty]

Ofishal wrote:
I m not familiar with the cobra transom hole but is it larger than the bravo? Could mean a transom rebuild which is probably due on an 88 anyway.

welshswampy wrote:
Yes, I think the cobra transom is smaller than the bravo. however, I've seen an adaptor transom plate which would overcome this problem

The plate is oversize so would cover the larger hole with ease

Check with those in the know.... but I believe that the OMC Cobra transom cut-out is the same basic size as Merc's.

There may be a bolt or stud hole or two that needs to be relocated... but again, check with those who know for certain.

The adapter plate that you speak of, is likely a plate that allows for an AQ series Volvo Penta, OMC Stringer Drive and/or the BMW transom cut-out to be closed down to accept a Gimbal system drive.



I could understand doing this for a BMW or Stringer Drive.

Back to the AQ series and Borg Warner idea for a minute:

If you have transom core concerns and were to do the Borg Warner-V/P install......, any immediate areas around the existing Gimbal system opening can be cleaned up.

The opening would need to be enlarged some anyway!

Been there/done that!

[Guest]

HI as stated diesel hear in the uk is more expesive. the omc transom cut out is more or less the same as the merk and diesel is more readily available in marinas around the uk. but why ow why would u want to replace a petrol engine that the parts are redily available and cheap.compeard to the derv counterpart. as for the transit engine are u sure ? noisy low powerd heavy nasty thing even in a transit .not to mention if u woz to fit one of thease engines yore boat would end up being worthless .id have a very long think on this one. the cost of replasing yore petrol engine with a diesel would cost a lot .and unles u woz to fit a new engine install the value of yore boat would be interesting. why not use the boat as is and do a lot of boatig on the money and time saved.