23 SEACRAFT PROJECT BOAT

[KenB]

Scott - I have 23 that was set up for twins sitting in my front yard. I did spend some time looking up jackshaft thread on CSC though. Is is possible to convert an OB boat to jackshaft?

The plan is a bracket and then a 250 ob. But I have access to some good clean biodiesel and have been considering a jackshaft and an old diesel.

I ask about that turbo powerstroke because the grease car guys love that engine.

[Fr. Frank]

The 7.3 Powerstroke engine is a 1960's International design now made by Navistar since they bought out International. Ford purchased most of the production of that engine for years. It is also marketed under the T444E designation for Navistar, and the D444T and D444E under the International nameplate. While most of these engines not sent to Ford were used in buses or small commercial trucks, there are marine variants of this engine out there, mostly marketed in Asia and Australia. Mahindra manufactures this engine for Navistar in the Asian market.

With regular proper maintenance, the 7.3 will easily exceed 500,000 miles, or 10,000 hours of operation. It can be tuned to produce between 215 and 700 hp (depending on how it breathes), and produce over 600 ft. lbs of torque.

My '02 7.3L was re-programmed by Ford during a recall in early '06, and according to the documentation, the HP rating went from 275 to 315hp at 2600 rpms, and the max torque went from 500 ft lbs up to 525 ft lbs. At the same time, my fuel economy went up by about 12%, from a combined average of 16.3 mpg, to 18.2 mpg. Since then I have gotten to the point of needing my injectors rebuilt or replaced, and my economy has fallen over the past 8 months to only 17.6 mpg average. I have over 200K on the truck, which is about the expected life-span of the injectors. Reman'd injectors are about $300 to $400 each.

[workinpr0gress]

I like the idea of a Cummins 4bt turned up some. Bread truck motor, shares tons of parts with the 6bt. Guys are turning them up fairly cheap and getting an easy, reliable 250-300 hp and 600-700 lbs. of torque on the stock longblock, you can run a continuos 40psi and spike for a bit to 60psi watching the pyros on stock headbolts, stud it and you could boost much higher, again reliably. Not saying you would or should, just saying the Cummins really doesn't mind being turned up and they have flatter torque than anything else and are cheapppp in a lot of cases. I'd just do injectors, a fuel pin, & a lift pump, it'll rip in a boat that size and still get great fuel economy. Just my opinion.

[ScottM]

Sorry Ken, when you said 7.3 I thought you really meant the gas 7.4, not the PSD. I have no experience converting a boat like this so I really can't comment if you can or can't do the jackshaft thing. I suppose with the right amount of money and skill anything is possible.

[KenB]

I guess that's why they have boat shows, right? To figure out how much the conversion will cost. I have no doubt someone will tell me it's possible... the issue is $$$.

The true world marine guys do a jackshaft, and I think I have seen the set up in the albin/cape cod 26. AND obviously Tug's boat is bada$$.

I just wonder why more guys have not done jack shafts in 23s. Price of tranny/block? Loud noises? (thanks brick tamland from anchorman).

Anyway if I can get the whole rig together for under 6k or 7k (including and old engine block that won't mind drinking kitchen grease) it's at least worth considering.

This seems like a good deal: ($5k buy now.)

http://cgi.ebay.com/ebaymotors/Konra...#ht_500wt_1182
"For sale is a Konrad 520 Diesel outdrive. The drive is in good condition and in proper working order with no corrosion issues. They have been checked out, filled with fresh gear oil and are ready to be bolted on and go. Great replacement for outdated TRS drives and other drives that cant handle the torque of the diesels. These will also work with gas engines. As you know Konrads are bullet proof and the only drive that can handle the abuse of commercial applications and high horse power and torque ratings. The ratio is 1.43 and can easily be changed by matching it to the appropriate ratio transmission, Serial number 5746. I have 14 drives available...and 8 complete transom assemblies...Also in stock are complete Bravo 2 drives and bravo 1 and 2 lower units complete and empty cases. Quantity discounts available trying to clear room in the shop.

All items are sold as-is where is. I will assist with shipping; buyer is responsible for cost. Drives are located in Westchester NY and can be seen anytime. If you have any Questions give Randy a call at (914) 384-9869. Thanks"

[KenB]

The 7.3 Powerstroke engine is a 1960's International design now made by Navistar since they bought out International. Ford purchased most of the production of that engine for years. It is also marketed under the T444E designation for Navistar, and the D444T and D444E under the International nameplate. While most of these engines not sent to Ford were used in buses or small commercial trucks, there are marine variants of this engine out there, mostly marketed in Asia and Australia. Mahindra manufactures this engine for Navistar in the Asian market.

With regular proper maintenance, the 7.3 will easily exceed 500,000 miles, or 10,000 hours of operation. It can be tuned to produce between 215 and 700 hp (depending on how it breathes), and produce over 600 ft. lbs of torque.

My '02 7.3L was re-programmed by Ford during a recall in early '06, and according to the documentation, the HP rating went from 275 to 315hp at 2600 rpms, and the max torque went from 500 ft lbs up to 525 ft lbs. At the same time, my fuel economy went up by about 12%, from a combined average of 16.3 mpg, to 18.2 mpg. Since then I have gotten to the point of needing my injectors rebuilt or replaced, and my economy has fallen over the past 8 months to only 17.6 mpg average. I have over 200K on the truck, which is about the expected life-span of the injectors. Reman'd injectors are about $300 to $400 each.

Sorry frank, I am little confused. Is the merc 7.3 this same engine block? Did this engine make it into boats? Is this too much motor for a 23 with jackshaft?

And Do I even want to consider marinizing on my own? There is a guy on the tolman skiff site who says down under (I think he is in new zeland) they regularly marinize diesel car isuzu and nissan engines. He is currently doing the conversion himself. Not sure what he is changing.

[ScottM]

Loud noises? (thanks brick tamland from anchorman).

"The bears can smell the menstruation". Okay, I have officially derailed this thread. I ran into Steve Carrell at the super market last winter around Xmas (he has a house in my town) and I chatted with him for a few minutes. Seems like a pretty down to earth guy but you could tell he just wanted to get on with food shopping.

[Fr. Frank]

Sorry frank, I am little confused. Is the merc 7.3 this same engine block? Did this engine make it into boats? Is this too much motor for a 23 with jackshaft?

Same block, but Mercruiser gets the D-Tronic 7.3L motor direct from Navistar, including fuel system and intake. No, it's not too much motor. The D-Tronic is rated at 270 hp, but produces 500 ft lbs of torque, compared to the measly 365 ft lbs of the 5.7L MPI gas motor.

Changing the D-Tronic over to the Ford fuel system and using the Ford computerized controller appears to be a process few have tackled, although one guy claims success, and says he Superchip'ed his motor and uses an aftermarket turbo to achieve 600 hp in a Baha 33' with a B2 drive.

So it can be done, but do you really want to be a trailblazer in this?

This is a case where I recommend the Volvo-Penta.

[KenB]

Thanks Frank that makes sense. Always enjoy reading your posts.

Is this cat too big?

http://boston.craigslist.org/sob/boa/2185609958.html



For Sale: (1) Caterpillar 3116 / 350 H.P Marine Diesel Engine With Z.F. 220 A, 1.533:1 Ratio Transmission. Running Take-Out. Listed On E-Bay As:# 300505857943 Price: $4,250.00 Offered and Sold As Is, Where Is As Shown. Cash and Carry. No E-Mails*.Best To Contact Me On My Cell Phone: (774)451-2889. Mon.- Sat. 8:00 -5:00

[McGillicuddy]

I don't know jack about jack-shafts but that seems like an awfully heavy motah choice for any 23... really tall too...