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Rebuild the Lehmans and 20 years from now you will still be happy.
 
I've actually just overhauled both engines, heat exchanges and exhaust pod. But before I could get it all installed, my mechanic quit and moved away. I have very young children and a full time job. I love my boat but foresee using it a maximum of a couple of hours a month for the next few years. Hence the outboard plan.
 
IanPereira said:
I've actually just overhauled both engines, heat exchanges and exhaust pod. But before I could get it all installed, my mechanic quit and moved away. I have very young children and a full time job. I love my boat but foresee using it a maximum of a couple of hours a month for the next few years. Hence the outboard plan.
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2 hours a month :eek: Why even worry about engines ??????
 
You are so far down the track with the Lehmans it makes no sense to switch to outboards, or anything else. Can`t be that hard to find another marine diesel mechanic in KL, or nearby.
 
Thank you everyone for the wise words. You've all convinced me just about to carry on with the current set up. Would be good if anyone would know where to find 2 sets of gauges and sensors f
For the engine.
 
IanPereira said:
Would be good if anyone would know where to find 2 sets of gauges and sensors for the engine.
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Try Brian Smith at American Diesel Corp. They are the effective successors to Lehman, have lots of parts, and likely know how to source those they don`t have. Email Briansmithadc@aol.com
 
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gaston said:
Thats a very good point and about 19 years and 9 months better than any Mercury :whistling:
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I'm in the market for a new ob, and I was looking at the Mercury range. They also sell remanufactured engines, and you can buy just the redone engine block and fit it to your old ob without having to purchase a new replacement .

I found the idea of exchange power heads and cheap spares an attractive idea.

Are Mercury ob's a disaster?
 
Rustybarge said:
I'm in the market for a new ob, and I was looking at the Mercury range. They also sell remanufactured engines, and you can buy just the redone engine block and fit it to your old ob without having to purchase a new replacement .

I found the idea of exchange power heads and cheap spares an attractive idea.

Are Mercury ob's a disaster?
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Like most businesses, Mercury survives on the quality reputation of their product and they have been in the OB business longer than I can remember. I have seen a lot of Mercury's 40 and 50 years old still running along. Like most engines, gas and diesel, proper maintenance and lack of abuse figures into the equation. There are people who love them and people that hate them like almost all other mechanical items. It's like loving Chevy's and hating Ford's.
 
Saw this boat near Ft Myers Fl. 6-7 years ago. Sorry, I have no idea how it worked out for them, and I never saw it again.
 

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Donsan said:
Like most businesses, Mercury survives on the quality reputation of their product and they have been in the OB business longer than I can remember. I have seen a lot of Mercury's 40 and 50 years old still running along. Like most engines, gas and diesel, proper maintenance and lack of abuse figures into the equation. There are people who love them and people that hate them like almost all other mechanical items. It's like loving Chevy's and hating Ford's.
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I hear what you're saying, often people take unfounded likes and dislikes to products.

Just have a look at this survey of ' iconic' brand names; surprising!

Who Makes the Most Reliable Motorcycle? - Consumer Report
 
Any gauge with matching sensor will work. Any automotive supply store will have what you need. You can spend as much as as little as you want.
 
In addition to Donsan's list of potential problems (post 20), and items mentioned by others... One of the biggest items (that was already mentioned in early post) is weight control regarding COG... for taking unruly seas. As well, I might mention that in addition to your huge COG shift by pulling the inboard engines you will be completely altering the boat's weight ratio design concept by placing much added weight "past" your boat's transom. Boats are designed by navel architects and their weight placements are taken into full consideration for hull design as well as superstructure layout.

In addition to boat design weight-ratio mix-ups... I can see outboards becoming huge expense, very difficult to get installed properly, problematic for cruising, and a complete killer for resale.

IMO - Two least expensive alternatives you have: 1. Find someone who can actually restore your existing engines. 2. Rip out the old diesels and install gasoline engines. Or... Sell that boat and buy another.

Unfortunately, no matter what you decide to do... you have MANY "Boat-Bucks" in expense ahead. :facepalm:

Good Luck!! and Happy Boat-Repower Daze! - Art :speed boat:
 
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Art said:
In addition to Donsan's list of potential problems (post 20), and items mentioned by others... One of the biggest items (that was already mentioned in early post) is weight control regarding COG... for taking unruly seas. As well, I might mention that in addition to your huge COG shift by pulling the inboard engines you will be completely altering the boat's weight ratio design concept by placing much added weight "past" your boat's transom. Boats are designed by navel architects and their weight placements are taken into full consideration for hull design as well as superstructure layout.

In addition to boat design weight-ratio mix-ups... I can see outboards becoming huge expense, very difficult to get installed properly, problematic for cruising, and a complete killer for resale.

IMO - Two least expensive alternatives you have: 1. Find someone who can actually restore your existing engines. 2. Rip out the old diesels and install gasoline engines. Or... Sell that boat and buy another.

Unfortunately, no matter what you decide to do... you have MANY "Boat-Bucks" in expense ahead. :facepalm:

Good Luck!! and Happy Boat-Repower Daze! - Art :speed boat:
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You hit it well and the reason I said I'd never modify in this way. If you wanted to then what you should do is hire a naval architect to design and consider all the factors. Obviously no one is going to, but you've changed the boat in a big way and tossed the original design out the window and you have no idea what you're going to end up with.
 
Yeah, it could work. I keep a small outboard on-board for my dingy, and have bracket I can attach to my swim step to mount the outboard in case I need to use the outboard to move my mainship if my single diesel were to fail. Only works in the mildest of conditions. Of course you're talking about a totally different situation.

From a resale perspective I'd say a pair a well maintained outboards hold their value pretty well. Down the road you might find yourself selling the outboards and practically giving away the hull.

From a handling perspective I'd be concerned about the keel. Your turning-moment is much farther aft and the keel is going to act against you, so it will effectively tilt you out. Too much on the back side of a wave and bad things could happen. Especially since you've removed 4,000 pounds of ballast (it was a twin diesel right). So your center of gravity is higher.

The other concern would be pulling back hard on the throttle and your wake catching up to you - it could swamp your outboards.

But you sure would have a lot of maneuverability - especially if you had that joystick control system.
 
I took a ride through Indiantown, FL today and stopped at the marina....always interesting. Maybe someone recognizes this 32 or so trawler with a full keel and skeg, but now with the shaft log plugged and glassed over, and a jack plate added for an outboard. Pretty nice looking boat and a good candidate for the outboard trawler. I didn't get out to check, but she looks like wood.
 

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Hi thanks for the pics. Was just wondering whether a 24 diameter prop with 21" pitch connected to a 3:1 gearbox turning at around 1700rpm will give the same thrust as an outboard prop 16" diameter 13" pitch connected to a 2.5:1 gear turning around 3000rpm
 
I apologise up front for my inexperience but what would be the cost to replace the existing diesel engine with a comperable new or refurbished engine?
 
Here is one concept....

Still a little houseboat origin...but certainly can be even further modified.
 

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healhustler said:
I took a ride through Indiantown, FL today and stopped at the marina....always interesting. Maybe someone recognizes this 32 or so trawler with a full keel and skeg, but now with the shaft log plugged and glassed over, and a jack plate added for an outboard. Pretty nice looking boat and a good candidate for the outboard trawler. I didn't get out to check, but she looks like wood.
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Larry,
An interesting boat indeed.
An OB will drive that boat fine w very little power.
But w that FD rocker the prop will come out of the water rather easily on seas. But for flatwater a great combination of boat and power.
 
It is complicated due to the numerous combinations and permutations involved.

For example, does boat have a generator? Hydraulic steering? Autopilot? Single engine? What HP is involved? You question is really too vague to take a stab at.

If you really want an outboard powered trawler, take a long hard look at the TT35 from Great Harbour. It is trailerable to boot.
 
Donsan said:
It is complicated due to the numerous combinations and permutations involved.

For example, does boat have a generator? Hydraulic steering? Autopilot? Single engine? What HP is involved? You question is really too vague to take a stab at.

If you really want an outboard powered trawler, take a long hard look at the TT35 from Great Harbour. It is trailerable to boot.
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No, your answer was perfect for me. I indicated that I am inexperienced and what you just informed me is good information for me to have.
 
adk1 said:
Does anyone have an idea??:whistling:
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It's only a guess, but it's a figure I use to justify maintenance and keep me from doing anything stupid: $25,000.

It's going to vary a bit depending on the engine. And of course if it's not a direct replacement, the cost could be quite higher.
 
It's not really a trawler but it's outboard powered:


Seen on the Potomac River near Washington DC. It belongs to the US Army so I guess it doesn't matter how the fuel mileage is.
 

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WesK said:
It's not really a trawler but it's outboard powered:


Seen on the Potomac River near Washington DC. It belongs to the US Army so I guess it doesn't matter how the fuel mileage is.
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Well that sums it up like nothing else can.:eek:
 
WesK said:
It's not really a trawler but it's outboard powered:


Seen on the Potomac River near Washington DC. It belongs to the US Army so I guess it doesn't matter how the fuel mileage is.
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Must really sing a song w all those engines slightly out of sync.
 
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