Inboard repower?

[PatMyGreen]

OK so I just pulled the trigger on a new (to me) 1989 30' SPORTCRAFT with twin 5.7 mercruisers. Right now I am using this boat as a 6-pack charter as it is alot more boat than the ole 26' snapper slapper and fuel economy under a full load is about the same, although I can take 3x the load. Both engines run great right now and one is effectively brand new.

What I don't like about the boat is that I feel like I am riding on a bomb. Gas inboards scare me alittle (the first hting I did was change the blowers) and I understand mercruiser and cummins have a new joint venture diesel out now. Does anyone have any experience with switching from gas inboards to diesels, a prefference for one diesel over another and why, and/or any idea how much I can realistically expect to spend if I go this route?

Like I said the boat runs great, and I like it.... but I am going to have this one awhile.......

[Jaizzen]

Alot "O" Money.

If anyone tells you anything different they are lying!

[KEYSKILLER]

diesel repower will be a pretty penny. does your boat have outdrives or straight shafts.

keep rockin it the way it is, once you blow one engine, the opposite engine will probably be pretty close to the same life span. sell the running engine and put the $ made from the running engine towards repower.

i ran mercruiser 454's, and 496's commercially. typical life would be 3000hrs. that was fresh water cooled, oil changes EVERY 100, and fresh flush everyday.

[PatMyGreen]

fresh water cooled, oil changes EVERY 100, and fresh flush everyday.
Roger that, I wouldn't run it any other way, either. One of the other reasons for thinking about tis is that diesel is a full dollar cheaper than gas at the marina AND EVEN CHEAPER THAN THAT IF YOU HAVE IT DELIVERED!! If the difference stays like that in the SUmmer months when I am doing most (80%)of my charters than they might be worth it quick like.

[Mariner]

Hope you have some DEEP pockets.....Motors,trannies,props,propshafts, spare props..labor to install, and re-rig it.......... :rolleyes: Take a look at Crusader's 6.0 MPI. Same size a 5.7,more displacement. More hp's than Mercruiser's 6.2 and lighter.. :thumps:

[Sherpa]

if you repower with diesel, and can still use the original trans, wouldn't you need to
change the gearing in the trans for the slower rpm's for the diesel's-?

--I'd think you'd have to.... probably most would just replace motor/trans combo.

--sherpa

[Southern Cross]

You will probably do better buying another boat with diesels and selling the one you have. It's hard to justify tearing up a perfectly good boat. I would just shop for something else. It's a buyer's market right now. Lots for sale to choose from.

[gogators27]

The Difference in price of one fuel over the other is chump change compared to the economy of a deisel over the economy of gas. But figure about 40k for a pair of new yanmars. it takes a lot of trips to justify that kind investment.

Interest, depreciation, down time for the install and break in, you may very well be better off just finding the right boat already rigged with diesels and selling yours. Good luck man!

[Kahuna]

Not trying to derail the post but whatever happened to the idea of using GM diesels. They will bolt right in. I know whey were shit in the beginning but they got better.

[Capt.Gene]

Don't forget to budget for bigger exhaust cut outs, 8 D batterys, return lines to your fuel tanks, and upgraded HD running gear.

[Steve-o]

From your reference to the Cummins-Mercruiser packages it sounds like you might have outdrives, which crimps your options. I looked at them briefly when doing my research for a stern drive repower, but the opinion of the west coast Cummins guru was that they are not that great (which turned me off). The big player in the sterndrive diesel market is Volvo, which I somewhat reluctantly went with as the lesser evil. There are other possibilities but the best advice I've been given on choosing a powerplant is to stick with something that you have good local support for. When it needs fixing, and it will, expert local support makes all the difference in the world between a month down and doing work yourself and being up and running in 72 hours.

If you want to get an idea of what you're up against on the repower, joining boatdiesel.com and reading some of the repower forums might be worth the $25.

I don't like gas too much either, but for me the deciding factor was range. There are no gas stations at sea. I can't comment on the economies of running 6-packs so your cost considerations might be different than the guys who are just out for a good time.

[Surface Tension]

I repowered my 24' Rampage with a 240HP Yanmar. I love the boat and I'm glad I've got a diesel, but if I had to do it again, I'd find a boat that already had a diesel in it.

My engine was about 18k out of the box. I had to upsize the shaft, new prop., shim the strut, dripless seal, fuel, return lines, LABOR, taxes, control panel. It can add up quick.

Dave

[scrounger]

at least 40k for that change. waite until you kill one of the engines you have in it now.

[Dangerous]

It may be cheaper in the short run to buy a gasoline bilge sniffer. Google fume detector or something like that. I used one when I had a gasoline inboard.

[PatMyGreen]

Thanks for all the feedback guys, 40k for a repower is within the realm of reasonable for that kind of repower, remember that am using this guy for charters so it gets a few hours. After sucking up 160 (x $3.68= $588.80!)gallons of gas two fridays back the difference in fuel cost alone will pay for the new engines in 3 years.

The thing about finging a boat with diesel already in it is that I really like the layout of this boat for charters and personal use. The next boat I buy I am is either gonna be something inspected for 12 or more passengers or a nice new Luhrs, just depends on how soon I hit those magic six numbers.

[Big Pig]

How about repowering with a single diesel?

[dive4bugz]

Hey Pat, also remember the other costs involved... youre looking at redoing the fuel system, complete flushout, etc, new lines to accomodate the diesel fuel, redoing a major portion of the electricals from 12 to 24V... not to mention if you have a generator, that also needs to be seitched out, or you have to run another fuel tank/electrical system for that, completely separate from the main drive engines... sounds like WAAYYYY too much work. Leave it alone, run it while its running, then sell her for diesels when you feel ready... just an opinion...

[Man-O-War]

Also, diesel still costs ~$3/gal....so it will be long ways before "they pay for themselves"

[Spear One]

How about repowering with a single diesel?

Yeah...........a single 390 hp Yanmar would get that boat runnin' pretty good.

[Surface Tension]

If you can get offroad diesel, it's going for about 2.50 a gallon, but even still if you run the numbers, you're looking at a lot of hours before you recover the added expense over a gas.

I second the single diesel option, but it might get expense to change the layout of your mounts and seals and such.

[gumshoe]

It'll take you forever to justify paying for that switch - unless deisel is 1/2 the price and your motor gets 2x the mileage while at cruise.

5.7 liter GM 350 is easy to get your hands on & replace. Should run for a long time & get decent fuel mileage.

I'd enclose the cooling system & run them like you want to. They'd run a little warmer, but they'll do OK with that.

Oh, and I wouldn't venture offshore thinking you're driving a ticking time bomb. That's a fantasy.

[ogredive]

Hey Pat,

Talk to Jody Kennedy 236-0061 at Marine Maintenance. I think he is off of Mcellvy Road. He just repowered a friend's topaz. Nothing but good comments about his products and services and his follow up customer care is exceptional. He should be able to steer you in the right direction and not screw you. My friend just repowered with volvos and is extremly satisified with the performance and efficiency.

[PatMyGreen]

Thanks Darryl, Jody is the son of the other Capt Pat from the Dive Locker so I may be giving him a call. BTW the Newton is here now and it is bad ass!

[gogators27]

Thanks Darryl, Jody is the son of the other Capt Pat from the Dive Locker so I may be giving him a call. BTW the Newton is here now and it is bad ass!

Lets see that Newton! Pics :thumps: