Curious...

Is there a good reason people don't (or do they...?) look at putting a modern V8 turbo diesel engine, say out of a wrecked F 250 or similar sized truck...powerful, economical, reliable if maintained, light for its size...naturally 'marinized'....am I missing something Ladies and Gents ?

AussieCraig said:

Is there a good reason people don't (or do they...?) look at putting a modern V8 turbo diesel engine, say out of a wrecked F 250 or similar sized truck...powerful, economical, reliable if maintained, light for its size...naturally 'marinized'....am I missing something Ladies and Gents ?

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I have wondered the same. I think one problem has been the slow boat sales of recent years. The design, tooling, and testing of marinizing of the diesels would not justify the cost. The relatively high manufacturing volume of these engines should in the future make them competitive for marinizing.

The new common rail electronically controlled engines produce an amazing amount of torque. The electronic controls would probably be another expensive factor. I look for it to happen as boat sales pick up again.

V8s are not as easy to access both sides as is a straight 6 or 4. Plus who needs a light duty short life diesel V8 in a low speed trawler? Marinization is very difficult to do right to justify the low sales. Don't forget the ubiquitous Cummins 5.9, a very popular marine and light truck diesel.

I've had similar thoughts wondering more specifically about diesel stern drives. I was surprised how few houseboats have them.

Monohull houseboats are popular on my local waterways and most of them have stern drives powered by gas engines. I understand these boats are built to a price point, however the price of these boats new puts them into a category that diesel should not add significantly to their price.

As many of them exceed 60' in length and cruise reasonably slow, diesel power seems a logical yet underutilized choice.

I've seen many threads at boatdesign.net outlining homegrown diesel marinization for one off re-fit projects including VW auto diesels. The VW projects are popular enough that there are many aftermarket marine parts available from short run producers.

CPseudonym said:

I've had similar thoughts wondering more specifically about diesel stern drives. I was surprised how few houseboats have them. .

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Stern drives and diesels have not been a good mix for longevity due to the higher diesel torque as compared to a stern drive with a gas engine. Perfect maintenance can alleviate some of this problem, as shown by R Cook who is on TF and cruises deep into the PNW in his vessel.

Diesel pod drives have proven much better than stern drives (and some say straight shafts) with the inherent design difference and heavy duty gear assembly able to take HP loads never conceived or possible for stern drives.

A gas stern drive or two on a large mono hull houseboat is pretty common. My BIL had one 65' X 18.5' on Laurel Lake in KY and it was a beauty, leaving the dock for a mile or two a week of cruising - hardly worthy of low hour diesel headaches.

I wasnt thinking of said engine as an option in new boats, rather as a replacement for worn out existing engines...and I wouldnt call a motor capable of 400,000 towing miles as 'light duty'...

AussieCraig said:

I I wouldnt call a motor capable of 400,000 towing miles as 'light duty'...

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Ford and GM pickup diesels are light duty in comparison to the 6 to 7 liter smaller but heavy duty diesels normally put in trawlers and fish boats. Pickup diesels are what they are, never intended for 8 to 10 gph of commercial rated fuel burn day in and day out as seen in heavy marine or industrial use. If buying a new million dollar trawler I'd never consider a Ford or GM, nor would any one else.

Your question could be rephrased to ask "why don't we see more pickup diesels in forklifts, small loaders or 150 - 200 kw gensets. With the exception of the Cummins 5.9 pickup engine, we don't. There is a reason.

The worst engine experience I ever had was the GM pickup diesel from the early 80s. My current history with Ford light truck diesels is much better, but the diesel cost per gallon vs gas has me questioning the overall savings (except when towing).

Sun-I think you also need to consider the duty rating of the engines. The same engine can have different duty ratings. For instance, our JD 6068s are continuous duty rated at 154 HP. The same engine can be setup for HP ratings from 135 to 250, generally at 2200-2400 RPMS, depending on intended use. A higher HP model is not suitable for the duty cycle anticipated (whether actually ran that way or not) in a trawler style boat. I would think the same would apply to the Ford or GM diesels. Can they be detuned for continuous duty, pushing heavy loads, running at 15-1800 rpms and be as efficient as current marine power plants?

Aha, I get your point, thankyou for the lesson...

.powerful, economical, reliable if maintained, light for its size.

AS noted above the auto HP rating would not be realistic for a boat.

IF the engine were sized so 1 HP for 3 cubic inches of displacement , a long term boat use would work just fine..

Esp for "trawlers" that need 30-60HP to cruise.

A hassle is many car , pick up truck engines use propiratiry bell housings , instead of SAE std sized .

So adding a marine tranny would require a special adapter.

300HP for 15 min would still be possible , so wake making would be excellent!

The engine would also need to be repainted for the environment in a bilge.

I have the 6.0 liter ford engine in my truck. I just put 200k miles on it in about 6 years. I don't have a problem using the truck everyday to go wherever. I would however worry about letting is set up for months on end and cranking it every now and then as most boats end up doing. Also with all the egr and epa regs on the diesel engine they develop a lot of carbon build up in the intake/turbo and the injectors are a little tougher to get to. I did just get all the injectors changed for $2400.00 and an egr delete for $1200, now my f350 gets up to about 20mpg at about 60mph on a flat road. Unheard of before the egr delete.

I did just get all the injectors changed for $2400.00 and an egr delete for $1200, now my f350 gets up to about 20mpg at about 60mph on a flat road. Unheard of before the egr delete.

Now you know why many OTR truckers will purchase a new "Glider" (no engine ir tranny) and install a pre 03 diesel.

Our VL 100 bus camper has a 96 DD Series 50 , for economy and trouble free operation.

Interesting that 2400 + 1200 would purchase a new gas crate engine that would probably drop in.

You have a source of red fuel that makes it worth keeping the diesel?

FF said:

You have a source of red fuel that makes it worth keeping the diesel?

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No, just the snow ball effect I guess. I started with the injectors and during that process decided to go the egr delete. I do tow trailers every now and then and need the torque. I looked into a cummins swap but the kit all by it's self was over 18k. I don't know if the gasser would just drop in and if it did would it require another pile of money to make it work. My truck has been very reliable in the past and I just look at it as an investment for the next 200k miles.

The last boat show I went to, one of the local diesel shops was marketing a marinized version of the Ford Power Stroke...just FYI

swampu said:

I looked into a cummins swap but the kit all by it's self was over 18k. .

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I "aquired" most of the Cummins marine addons for about 1/18th of that over the course of about 3 years and that also included a usable engine out of a pickup truck and a BW tranny that could handle the job. I aborted the project only because I decided not to put any more $$ into the boat.

Baker said:

The last boat show I went to, one of the local diesel shops was marketing a marinized version of the Ford Power Stroke...just FYI

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The old Navistar T444 engine which was the powerstroke would have been a great marinized engine. Like the Cummins is was a commercial truck engine.

Unlike the Cummins though it was a V8 so it took up more room width wise than a straight engine like the Cummins. That also made it taller than a V8 though.

I think the Cummins popularity isnt necessarily because its a better or more durable engine, I think its because Cummins decided long ago that the marine market was a market they wanted to be in, so they developed, then refined a marinization stratagedy, along with a dealer network to sell and support it.

Baker said:

The last boat show I went to, one of the local diesel shops was marketing a marinized version of the Ford Power Stroke...just FYI

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So maybe my pondering wasnt so crazy after all....I will however wait till smarter people than me use them extensively and give the thumbs up....hopefully my 671 will outlive me anyways....

Ford Power Stroke...just FYI

This was probably marketed as a replacement for a gas engine , IO? or similar , probably not for a displacement boat 24/7 operation.

FF said:

Ford Power Stroke...just FYI

This was probably marketed as a replacement for a gas engine , IO? or similar , probably not for a displacement boat 24/7 operation.

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You know as well as I do FF that it is all a matter in how the engine is (de)rated. But yes, I believe it to be aimed at the recreational market.