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I have a 32' Luhrs sport fisher with 318 Chryslers. I am looking at replacing the gas engines with some diesels.. Can anyone suggest maybe a good replacement? Im not worried about straight out speed just mainly on saving on fuel milage and fuel expense, plus im looking to get rid of the fear of gas fires, and explosions. I have talked to a few people with the same boat with the Perkins diesel but they say they are too heavy. I cannot find the weight of them online anywhere.
Sell the boat and buy something with diesels. I know after upkeep and updating you feel like its worse to start over with a new boat when everything is how you would want it that its dumb to sell and change, but with mid level boats like older Luhrs it doesnt make sense fiscally to repower with diesels.
That said, if youre determined to repower, it depends on how much engine room space you have. 315 Yanmars if its tight, but I would say remanned Cummins would be the most economical choice if they fit.
__________________ 1999 27' Sea Ray Sundancer Special Edition
1988 34' Luhrs 342, Sold
1978 20' Robalo w 1993 225 Yamaha, 8 month rebuild, including Alexsealed, wiring, electronics, canvas, For Sale
1984 18' Regal bowrider, Sold after 14 years
1967 12' Jon Boat w 1967 Mercury 5 hp, family has had since new
I have a 32' Luhrs sport fisher with 318 Chryslers. I am looking at replacing the gas engines with some diesels.. Can anyone suggest maybe a good replacement? Im not worried about straight out speed just mainly on saving on fuel mileage and fuel expense, plus im looking to get rid of the fear of gas fires, and explosions. I have talked to a few people with the same boat with the Perkins diesel but they say they are too heavy. I cannot find the weight of them online anywhere.
Thank you.
Putting diesels in that boat is so far from cost effective it's shouldn't be mentioned..
You are talking 80-90K to do it right..with a pair of 6BT Cummins 250hp. Then you'll need another 15-18K worth of Troll valves if you want less that 7-8kts on one engine at idle because of the lots bigger props a diesel needs. Then hope the prop shafts have enough angle to be able to swing bigger props. If not we are talking remounting the engines higher and glass work to reset a shaft log, new struts.. That's 10-15K worth of work..
Fuel tank conversions to handle return lines for fuel. Might as well replace if the boat is as old as I think..
If the boat has 318's she's no pup... If the engines are running well, run them. You can eliminate 99% of the fire problem with electronic ignitions and new wires to handle the system. Then make sure your fuel tanks are in good condition along with the fill/fuel/vent hoses and any valves in the fuel system.
Then have a qualified electrical/electronic guy like Sea Sparks go thru the boats wiring. Then pay attention to what he recommends..
Engine compartment auto fixed fire extinguisher systems
Not to mention you can repower with a set of 350 Chevy's for 20K. Probably has a set of BW Vs trans already in her.??
Unless you can find a set of well worn 250hp Cummins Bt's with gears...then have a good buddy that knows how to deal with this swap...and has lots of free weekends.. Those 6 cylinder Bt's I've seen with 10-11000hrs on running just fine... Commercial boats where they sit around.. But you really need almost give aways to make your deal work.. A set of used diesels with 3000hrs left in them is what to look for... http://www.boats-and-harbors.com/ You might find those engines there..called the yellow pages for commercial boats..
Well I have currently been remodeling this boat. All the wiring has been removed so all new 110/12v wiring system, minus the engine harness cause I hadnt decided what to do. It will all up to AYBC specs. The fuel tanks are in great shape and I can machine any bung I need for a return line, or get new fuel sending units with return bungs on them.
How much bigger prop would it need, or how much space should be between the prop and the hull? I have the boat out of the water and is at my house now so I would like to finish some of this up before I go much further and put it in the water. The chryslers are coming out so I can re paint the engine room, and the bilge. I am also looking at re doing the back deck with glass over wood so having them out and then if I decided on a repower and if I had to move some of the floor supports this would be the time.
With all this new information I may be farther away from this plan then I intended!!
If price is no object, the easiest swap would be for a set of Steyr 220 or 260 hp diesels. They are 4,000 rpm motors, so you may be able to use your shafts and struts if they are 1-1/4" or bigger. They are the same physical size and weigh the same as 5.7L Chevy's and with a set of ZF63A's, would make a nice overall package. Downside, the engines and gears alone will set you back $60k; then there is all the labor to refit an install. If $80-90k for a repower doesn't scare you, this or the small 220-260 hp 4,200 rpm Yanmars (slightly cheaper) would be a great option too.
Take a look at the Iveco line, have a couple light models with the hp needed that are good replacements for gas conversions. Priced right also. Depending on where you are located, Mid-Atlantic Engine for northeast and Hugo Stamp in southeast.
LI32, I wouldnt say price is no object, I dont have tons of money to throw at the boat. I surely wouldnt throw 60k at it yet alone 80k. My thinking is with the way I have seen some used engines for I just didnt think the project would cost more then 20-25k, and even that may be too high of a price to dump into the boat. I can handle all the labor it will take. I more then have the capabilities to swap and engine/trans and anything else that would take labor. Maybe im just thinking way off course with the whole idea..
CTW, Im located in So. California. I will search out that line thanks.
If this is the original luhrs 32 I have spent alot of time on one that was repowered with twin yanamr 4 clyinder diesels at 140 hp each and the boat cruised at 14 kts and topped out at 16- 18. This is kind of underpowerd and i figure the 240 hp yanmars would probably push the boat just fine.
There are companies that do these engine swaps and I think your best bet is to contact one or two and get their advice. If you try to do it yourself or with the help of your buddies, you stand a good chance of making some poor choices.
I would stick a pair of new mercruiser or crusaders 6.7/6.2 in there - maybe do the MPI version with electronic ignition. Upgrade blowers and fire suppression. have your transmissions rebuilt/checked out.
You can burn a lot of gas for what it would cost you to stick some diesels in there
__________________ Jeremy
1995 Pursuit
1986 Bertram
If you go to boatdiesel.com, join and than you can look up information/specs on any engine. I am attempting to do the same thing as you. Convert from 454s to diesel. Running take outs are scarce, but Cummins does offer remans. I had two boats with the Yanmar LH series 4 cyl, and the 240HP version would probably fit an have enough power for the boat, although the 6btas in the 300-330HP would be far better if they will fit. More Power and parts are cheaper. At boatdiesel.com they also have calulators you can plug in your numbers and get performance information for various HP installs, prop information, etc. Another good site is a boat facility on the west coast Seaboard Marine. The owner has vast knowledge of this business and freely shares his knowledge both at his site and as a moderator on Boatdiesel.com. As an aside I am motivated by the ethanol in fuel problem. I am 24 miles from the nearest on water supply of fuel for my gas hogs. I had a diesel fuel tank on a trailer and bought off road diesel fuel, but all the gas station in this area will be selling only ethanol fuel in the next few months. I know one can't justify the cost to convert to diesel in fuel cost savings but the safety, ease of maintenance etc. is worth it to me. A few months ago there was an ad on boatdiesel.com's ad. site for a pair of running take out cummins 315s with gear for $18,500. I called but they were sold. That was for two engines, tx, not one and if you can do the work you can get in business for far less than the $80,000 or $90,000 talked about.
Last edited by raymonds; 11-18-2009 at 06:54 AM.
Reason: add information
If you get engines for $18k or so, there will still be materials needed for other possible upgrades to shaft, fuel tanks, rudder, mounts, etc etc etc. So you would be up to probably $25K in expenses not counting labor. Do the work yourself (not easy but doable) and labor is free. I still think that is too much to invest in that boat.
As regards safety with gasoline, open the bilge everytime you start her up and put your nose down low and smell. This is still one of the best safety precautions for gasoline fumes that exists.
Good luck with your boat, I say run her until the 318's die and figure out your next move then. Sometimes those old motors run forever.
I repowered my 31 tiara from gas crusaders 454 to volvo tamd 41p back in 2005/2006. Bought both engines and gears for 10 grand used out of a 28 carolina classic. Sold my gas engines and gears for 5 grand. Onetamd 41 p engine was fine one had a melted piston from a overheat . 400 hrs on both. The volvos 41 are wet liner engines.. for about 1000.00 pulled the one liner and replaced. The rest of the engine looked new inside. I installed both engines and the boat ran the same speed as the big blocks burning half the fuel. It was alot of work but in the end it was worth it. Total outlay was about 10 grand after selling the gas engines.
......... Do the work yourself (not easy but doable) and labor is free. ............
If one has the knowledge and skill to do this sort of work, one could find someone to pay for it. The labor is not "free" in the sense that he could be earning money for his time.
Thanks for the post guys. I didnt realize until I re read it that I didnt put the year of the boat. It is one of the original 1968 32' Luhrs Sport Sedan Sportfisher. It has a glass hull, and flybridge with mahagony interior.
Greg we use to spend most time around 10-12 knots anyhow just becasue of fuel consumption. If the thing cruised at 14 Id be tickled with that.
Ive definately gone overboard with my bilge blowers, lifting hatches and all that in the past. I am just trying to minimize the danger. My kids are older now and I would like ot take them on some of the more serious fishing trips we do. But it would sure be nice not to have to refuel everyday. The fuel tanks on it are nice big 110 gal tanks (measured so may not be exact but real close) so that would be 200 gals of diesel that should take us far. Not to mention the cost of diesel here is $2.40 and gas is $3.60.
The 318's run fine. I am a very qualified mechanic and have taken care of the running gear on this boat to a tee. My main reason for thinking of the swap was because I spent a lot of money moving the boat to my home so that I could remodel, re paint, and do a few upgrades. I need to remove the 318's to repaint the engine room, and bilge area so I fiugred maybe now was the time. I am in the process, with a friend of mine who does marine electrical and has been qualified for little over 20 years am replacing all the wiring, most switches and many other electrical items. I had all new tempered tinted windows made for the boat and a few other items re done as well. I can attest to the fact that the boat will never be worth the money put into it, but the fun gained out of it will repay for the remodel and upgrades.
I will join the boatdiesel.com and have a poke around there as well.
JCJP I was thinking in the range of 10-20k for the whole job as well. Plus there is a guy who is looking for a good running 318 and i could probably sell him my set for a good deal.
I need to do a little more homework on the job I guess first and try to find some people in this area that do that kind of work.
I just hate to get rid of the boat because it has gas engines, and then have to drop 50k on a decent used one that I will no doubt have to do work on as well. Plus this boat has a great fishing deck and a cozy little cabin when the family and I go to the island.
hi RracnRod if u did go with the yanmars i would highly recommend the 200 hp version because the 140 hp is just not enough and when the boat is heavily loaded and in rough seas the boat just feels as it needs more power. also with the 200's you will be able to cruise at that 14kts at a lower rpm. with my friends 32 , 1973 model we make 14 kts but at 3100 rpm .
Greg,
Did your friend keep the same v-drive and shafts? One of the post stated about bigger props, do you know what size he had, and if there is an idle speed problem? I think it is really a project I would like to do, especially if there is knowledge out there that it has been done like you friends. Im just wondering what all I would have to change. The 200hp and 240hp are the 6 cyl. Room is not a problem but i dont want to change the weight cg much.
my friend was able to keep the v drive configuration and use the same gearbox and shafts. only one problem is beacuse the chrislers turned opposite ways and the yanmars turn the same way he has 2 left hand props because the v drive gearbox cant take the full load in reverse. one thing to considder is putting a bigger thruhull for the water intake for the main engines. will be happy to answer any more questions. idle speed is not a problem since the yanmars are high revving diesels and the boat floats pretty level with the 140's so i cant imagine the 240's or 200's weighin much more
Diesel Engines 
