hey yall gotta 6.9 in my boat

[Spencyg]

Nice research on the 7.3.

The one thing you will notice, the 6.9 will be a ton of weight in a 25' boat. ...

...

Just know you won't go anywhere in a hurry.

The few boats I've seen with the marinized 7.3's complained about lack of speed, never lack of power or reliability.

The engine I'm replacing with the outdrive weighs about 800lbs and is directly at the back of the boat. The 6.9 will probably weigh around 1200lbs in marine trim, and will be 8' forward of the transom. I suspect balance won't be a problem.

As far as the boat being slow, I guess it depends what you mean by slow. I consider a 20 knot cruise to be more than adequate, and with the drivetrain in question, that won't be a problem. I don't know if you've even gone 40 knots on the ocean before, but in all but the calmest of days, your back couldn't take it, no matter what the hull shape.

I've done the hydro calculations (rough) for my particular hull, and at a 7000lb loaded displacement I'll require about 100hp to cruise at 20 knots. The IDI with a turbo should burn around 1 gal of diesel per hour for every 18 or so HP generated at cruise. So at 20 knots and 100hp, I should be burning around 5.5 gals of diesel per hour. 20 knots is 23 statute miles per hour, so my rough calculated cruise efficiency should be in the neighborhood of 4.2 MPG. I can live with that.

I've just acquired a 6.5L GM marine diesel (total garbage) with all of the pumps, coolers, and a water cooled turbo. I'm parting out all of the 6.5L specific stuff right now, but have nearly everything I need for the actual marine conversion besides the manifolds which I will be fabricating.

This is a great thread.

 

[CaptTom]

The engine I'm replacing with the outdrive weighs about 800lbs and is directly at the back of the boat. The 6.9 will probably weigh around 1200lbs in marine trim, and will be 8' forward of the transom. I suspect balance won't be a problem.

As far as the boat being slow, I guess it depends what you mean by slow. I consider a 20 knot cruise to be more than adequate, and with the drivetrain in question, that won't be a problem. I don't know if you've even gone 40 knots on the ocean before, but in all but the calmest of days, your back couldn't take it, no matter what the hull shape.

I've done the hydro calculations (rough) for my particular hull, and at a 7000lb loaded displacement I'll require about 100hp to cruise at 20 knots. The IDI with a turbo should burn around 1 gal of diesel per hour for every 18 or so HP generated at cruise. So at 20 knots and 100hp, I should be burning around 5.5 gals of diesel per hour. 20 knots is 23 statute miles per hour, so my rough calculated cruise efficiency should be in the neighborhood of 4.2 MPG. I can live with that.

I've just acquired a 6.5L GM marine diesel (total garbage) with all of the pumps, coolers, and a water cooled turbo. I'm parting out all of the 6.5L specific stuff right now, but have nearly everything I need for the actual marine conversion besides the manifolds which I will be fabricating.

This is a great thread.

Sounds like a great project and that you've done the calculations to get'r done.

And yes, I've done 40knots on the water.... actually, my top speed is 96 knots, with many under-way's averaging 70 knots...that is 80.5 mph. This is normally the type of speeds I'm referring to when I say "flying a boat".

My small boat only does 36-38 knots, now the fastest I own.

20 knots is not unusually slow, especially at cruise. The reason I mentioned slow is, most folks I've encountered have been Chevy/Ford gasser users. When comparing the two for performance, the proof is in the pudding... gettin' there! Although performance is a combination of factors, speed is under most comparisons what everyone wants, especially in a recreational fishing boat where time is the premium.

Off the coast of SoCal, most big tuna fishers like to go 70-100 miles for their catch, leaving on Friday afternoon. They wanna get there to soak their bait... so yes, speed is of great importance. As we all know, speed is the first to leave the equation when weather builds to a chop. As you suggested, bodies don't like it very much, either does equipment.... and why commercial guys go for slow moving, fuel economic, torquie engines. They live it daily and must pay for it our of their income stream... broke boats that pay the bills cannot sit on a trailer in the back yard.

Since time is directly related to speed, if you gots the time, there ain't no point in speed.

20 knot cruise is good enuff, but is it really speed???

Notice we've never suggested reliability in the argument, it's all been about performance.

I love the idea of an IDI in a boat, at least 28' long, shaft drive, a pair in a 32' would make it ideal...but less economical. Of course, with my experience of my 6.9 I used to own in an 84 F250, I'd never choose that engine again, gutless wonder from Hades, but, I would certainly use a 7.3l IDI all day long....huge power difference.....and forget the 6.2/5's from anything.

 

[oldmisterbill]

Well I have my way like every one does. I like a good cruise speed -the 40 70 MPH is BS,anyone can beat themselves to death,and be exhausted from a quick beating back to shore. A reasonale cruise -comfortable -dry-and reasonably efficient on fuel makes sense to me. I was never impressed with gallons per hour as a mesuremant of economy. Hey if 20 gals last 4 hours and I can't make any time on a trip that winds up 5 hrs-I'm screwed. The Coast Gaurd can make a good example of a uythat runs out of fuel.I want to know what I am averaging in MPG the trip is 40 miles no matter how long it takes.

Speaking of the 2lb sledge -it reminded me of a time crusing at around 25 in a chop -on a cold November day heading out to do a little cod fishing to stok the freezer for winter. I hit my first real rogue wave,the water under me just vanashed and there I was looking down marbe 10-15 ft. Quite a rid when you weigh over 2 1/2 ton in a freefall with no parachute. Boy that water was hard "good to have a hull you can trust" and a deep V to cut a little & cusion the landing a little. It took my back a month to recover -we had a good catch that day so it was worth it.

 

[CaptTom]

Well I have my way like every one does. I like a good cruise speed -the 40 70 MPH is BS,anyone can beat themselves to death,and be exhausted from a quick beating back to shore. A reasonale cruise -comfortable -dry-and reasonably efficient on fuel makes sense to me. I was never impressed with gallons per hour as a mesuremant of economy. Hey if 20 gals last 4 hours and I can't make any time on a trip that winds up 5 hrs-I'm screwed. The Coast Gaurd can make a good example of a uythat runs out of fuel.I want to know what I am averaging in MPG the trip is 40 miles no matter how long it takes.

Speaking of the 2lb sledge -it reminded me of a time crusing at around 25 in a chop -on a cold November day heading out to do a little cod fishing to stok the freezer for winter. I hit my first real rogue wave,the water under me just vanashed and there I was looking down marbe 10-15 ft. Quite a rid when you weigh over 2 1/2 ton in a freefall with no parachute. Boy that water was hard "good to have a hull you can trust" and a deep V to cut a little & cusion the landing a little. It took my back a month to recover -we had a good catch that day so it was worth it.

BS?!?

You ever seen a 36' Fountain with two 525's and racing drives? It'll do 90 easy....not so easy in a Pacific swell and chop on top. And yes, I've been over plenty of those deep black missing sections of water, although the drop is painful as you expressed, there's one worse scenario.... bow plunging the bow into the next wave and wearing your windshield a thousand pieces at once in your face.

The fun part of the ride is taking passengers into hard turns.... sometimes they go involuntarily swimming!

Fuel limitations are fuel limitations... knowing the vessel you ride is important, however, if one could squeak another half gallon an hour out an engine through "performance" changes, letting one go further/faster, why not do it?

One last sea story... I worked in the Bering Sea for awhile, aboard a 300' factory trawler. One day the WX was really bad and we thought we had a full net of fish... it could hold 110 tons of fish. Well, we thought we had the mother lode!

The stern sank low and as all trawls do to avoid the nets from wrapping props is to motor down swell. That is, the waves/WX hitting the stern and riding underneath to the front of the ship.

The net was very heavy and the main winches were struggling to haul back the catch. When we dropped our stern door to bring the net aboard, we shipped a wave onto the trawl deck. CR@P! OH SCHNITZ!!!!! Surfing up to my waist in ice filled water!!!!! The ***** slammer was trying not to get sucked out to sea... a few motivated deck hands that day!!

We got the net aboard and all there was, was a few hundred Cod and a huge boulder!

Almost lost my life over a freakin rock!!!

Took us four hours to cut it out of the net, the crane couldn't lift it. We had to rig some blocks to the main winches to roll it off the back deck..... unbelievable day! The next 12 hours was spent sewing net....

 

[plywood]

Oooh, Sea Stories....

I remember a few years ago, in the Ocean a few miles out of Nehalem bay in an 18ft flat bottom sled, seeing a couple of killer whales, thinking how easy it would be for them to capsize our boat.

When I was about 12, I was messing around in the mouth of the Columbia in a 10ft twin hull Livingston, going with the wind and waves for a while having a blast, then turned to head back into it, and could barely make way going up the steep side and having the wind catch the under side of the that boat and launch up in the air nose high with the prop coming all the way out of the water.

I had a 21ft plywood boat named Plywood, that I did some Salmon trolling in. I remember one day we went out of Ilwaco and saw nothing but fog, all day and on the way in I used a handheld GPS to navigate the bar, never saw a buoy or a jetty or anything till I saw the entrance of Ilwaco.

That Columbia can be a total ****** though, my buddy and I were waiting for the Ebb to cool down and yet slip in before dark one night, but that tide just wouldn't slow down, having no radar or major lights, I had to fight that freaking tide rushing out at what seems like 15 mph as I'm climbing 9-12ft rollers in a 21 ft boat, and it's getting dark and there are freighters in the channel.

The Nehalem bar is another bad one around here, I grew up playing around in the Nehalem crabbing in that 10ft livingston. Although it works good when the short seep waves are coming in the bar, my buddy and I would just keep fishing as the 20ft boats are heading in. As long as I held the 9.5 horse Evinrude and he handled the rods, we could stay and catch Salmon.

I guess I just love the water, I've ran jet boats all the way up the Clackamas river in inches of water, and fished so many lakes and rivers around here I'm sure I've forgetten more fish than I remember. I go out in the Columbia on stand up and sit down jet skis and fly 6-10ft in the air. For fishing I was kind of ruined by Salmon trolling, nothing else seems fun after that. I'll do it again some day though.

I totally rebuilt that old homemade plywood boat, ground down the hull, fiberglassed it, and replaced the engine and frehened up the 1963 or 64 Mercruiser with the iron duke and I've never been towed by the Coast Guard in any boat Although I was rescued off of a log in the middle of some white water after my buddy sunk his driftboat, made it on the front page of the Tillamook Herald.

No Bering Sea stories, although I'd love to go, maybe as ship cook and engineer, relief captain. I spent alot of time as a kid on the docks in Warrenton/Hammond at the mouth of the Columbia and have always loved Commercial boats.

I would love to some day buy one of the old wood Salmon Trollers about 32ft with a small diesel and use it for sport fishing or maybe get a Salmon Troll permit again and hand line some more Chinooks.

 

[FordGuy100]

Oooh, Sea Stories....

I remember a few years ago, in the Ocean a few miles out of Nehalem bay in an 18ft flat bottom sled, seeing a couple of killer whales, thinking how easy it would be for them to capsize our boat.

When I was about 12, I was messing around in the mouth of the Columbia in a 10ft twin hull Livingston, going with the wind and waves for a while having a blast, then turned to head back into it, and could barely make way going up the steep side and having the wind catch the under side of the that boat and launch up in the air nose high with the prop coming all the way out of the water.

I had a 21ft plywood boat named Plywood, that I did some Salmon trolling in. I remember one day we went out of Ilwaco and saw nothing but fog, all day and on the way in I used a handheld GPS to navigate the bar, never saw a buoy or a jetty or anything till I saw the entrance of Ilwaco.

That Columbia can be a total ****** though, my buddy and I were waiting for the Ebb to cool down and yet slip in before dark one night, but that tide just wouldn't slow down, having no radar or major lights, I had to fight that freaking tide rushing out at what seems like 15 mph as I'm climbing 9-12ft rollers in a 21 ft boat, and it's getting dark and there are freighters in the channel.

The Nehalem bar is another bad one around here, I grew up playing around in the Nehalem crabbing in that 10ft livingston. Although it works good when the short seep waves are coming in the bar, my buddy and I would just keep fishing as the 20ft boats are heading in. As long as I held the 9.5 horse Evinrude and he handled the rods, we could stay and catch Salmon.

I guess I just love the water, I've ran jet boats all the way up the Clackamas river in inches of water, and fished so many lakes and rivers around here I'm sure I've forgetten more fish than I remember. I go out in the Columbia on stand up and sit down jet skis and fly 6-10ft in the air. For fishing I was kind of ruined by Salmon trolling, nothing else seems fun after that. I'll do it again some day though.

I totally rebuilt that old homemade plywood boat, ground down the hull, fiberglassed it, and replaced the engine and frehened up the 1963 or 64 Mercruiser with the iron duke and I've never been towed by the Coast Guard in any boat Although I was rescued off of a log in the middle of some white water after my buddy sunk his driftboat, made it on the front page of the Tillamook Herald.

No Bering Sea stories, although I'd love to go, maybe as ship cook and engineer, relief captain. I spent alot of time as a kid on the docks in Warrenton/Hammond at the mouth of the Columbia and have always loved Commercial boats.

I would love to some day buy one of the old wood Salmon Trollers about 32ft with a small diesel and use it for sport fishing or maybe get a Salmon Troll permit again and hand line some more Chinooks.

What rivers did you run jet boats on? My parents have a 21' North River and love doing that stuff.

 

[CaptTom]

That's some great stuff plywood.

I had a similar experience at about the same young age with my buddy's dad's 8' green Sears-n-Roebuck plastic boat. Don't remember the engine size, but we were fishing up the Snohomish River, dodging dead heads, well time to get back to the Everett Yacht Club... his dad was a richierich... The tide was a comin; in strong. As you know with the Columbia, a flood tide builds big rollers, hundreds of 'em with a strong flood. O!! Yeeeeeeup.... we were bailing and stupid, and bailing, and bailing some more, then some more bailing.... I think this went on for 2 hours in about a 2 mile stretch!

How we got out of that without drowning ourselves or sinking that boat I'll never know. Stupid kids! We had no clue what we were doing. I think our only motivating factor was, we'd better get his dad's boat home or we were both gunna get killed!!! We'd have been better off drowning!

 

[plywood]

Yeah, it dosen't take much, coming in about three hours up hill to get to the mouth of the Columbia one day after being in the fish going with it to the South, we were filling up with water from spray, and finally I went back and pulled the engine cover and my buddy had thrown a piece of plastic wrapper down on the floor and it ended up in the bilge pump. Same guy that almost killed me in his drift boat, go figure.

For jet boating I've done mostly the Clackamas in an 18ft flat bottom Alumweld Sea Dory with a 115hp evinrude pump tiller handle. All the way up from the Willamette past Carver, if anyone knows where that is. Went up the Sandy a little and did the mail boat trip on the Rogue, which is pretty crazy. Jet boating is a blast, nothing like looking out the side of the boat going full speed and seeing rocks a few inches down. All you can do then is keep going.

Rafted the Deschutes and the upper Clackamas. Drift boat fished on the Nehalem, South and North Fork, Wilson, Kilchis, probably a couple others I'm missing.

Oh, Yeah, almost forgot, also did the oversize sturgeon fishing on the Columbia, caught one about 10 ft, didn't measure it, I do have it on tape, but it's analog.

Not trying to brag by the way, I just don't get to do that stuff near as much anymore so it's fun to relive.

 

[CaptTom]

Yeah, it dosen't take much, coming in about three hours up hill to get to the mouth of the Columbia one day after being in the fish going with it to the South, we were filling up with water from spray, and finally I went back and pulled the engine cover and my buddy had thrown a piece of plastic wrapper down on the floor and it ended up in the bilge pump. Same guy that almost killed me in his drift boat, go figure.

For jet boating I've done mostly the Clackamas in an 18ft flat bottom Alumweld Sea Dory with a 115hp evinrude pump tiller handle. All the way up from the Willamette past Carver, if anyone knows where that is. Went up the Sandy a little and did the mail boat trip on the Rogue, which is pretty crazy. Jet boating is a blast, nothing like looking out the side of the boat going full speed and seeing rocks a few inches down. All you can do then is keep going.

Rafted the Deschutes and the upper Clackamas. Drift boat fished on the Nehalem, South and North Fork, Wilson, Kilchis, probably a couple others I'm missing.

Oh, Yeah, almost forgot, also did the oversize sturgeon fishing on the Columbia, caught one about 10 ft, didn't measure it, I do have it on tape, but it's analog.

Not trying to brag by the way, I just don't get to do that stuff near as much anymore so it's fun to relive.

Tellin sea stories isn't necessarily bragging, it's personal story telling.

What's funny about sea stories is, most people can't relate to them unless they've been there. I've been at sea since just a lad, over 40 years... that's a lotta time on the water with lotsa stories to tell.

I can appreciate your jet boat story. Never done the river/rock thingy, but have done 30 knots paralleling surf zone's in 11meter jet RIB's. Like the rocks just inches away, keeping the bottom out of the dirt and waves from crashing into the boat or overturning, and steering up-n-over the crests to avoid those situations is pretty tenuous.... but man! Does it ever get the blood pumping!!!!

I've watched those guys on the tube who race little jet boats in a course all twisted up and requires laser concentration to get through the course. Quickest time wins.

BTW- I love Alumaweld boats.

 

[plywood]

That's it, never more alive, I tore off and skil sawed and repaired sheeting and reroofed a 12/12 pitch roof, as I said, but that didn't even phase me compared to crossing the Columbia or Nehalem bar, some days I get out there and in the Ocean where it's calmer and I'm shaking like a leaf and loving it.

I've spent quite a bit of time out in the Ocean, nothing like a Sea Captain, but seen Whales, Porpoises, Sharks, Sunfish, Orcas, etc, and caught the Blue Shark to boot, although he bit through the tuna line doing the twisty right next to the boat, just about a six footer is all, but lots of teeth.

When I had Plywood, I ran two wires on hand Gurdies with no poles or floats and I think my best day was 30 Silvers and 3 Chinook, that was after throwing back at least twice that many wild ones. Pretty fun for my buddy and I who were used to coming back in after 4 fish. That and going up the shallow rivers in jet boats to fish are my favorites now a days, not that I've done either for a few years. Did make it out of Tillamook bay once this year.

Alumaweld is really making some nice Ocean boats these days, and they seem to be the only ones you can depend on being around through the tough times. I've known one of the guys over there for years, they build them and sell them and warrant them.

I've fished on North Rivers boats, 19, 21 and 23ft boats, all open boats with tiller handle pumps, they are great, the 21 is the perfect size and width, but they are banko, like so many other.

Here's a picture of a nice fishing boat, and since we're so far off track I thought I'd mention, it could have an IDI in it.

 

[CaptTom]

That's it, never more alive, I tore off and skil sawed and repaired sheeting and reroofed a 12/12 pitch roof, as I said, but that didn't even phase me compared to crossing the Columbia or Nehalem bar, some days I get out there and in the Ocean where it's calmer and I'm shaking like a leaf and loving it.

I've spent quite a bit of time out in the Ocean, nothing like a Sea Captain, but seen Whales, Porpoises, Sharks, Sunfish, Orcas, etc, and caught the Blue Shark to boot, although he bit through the tuna line doing the twisty right next to the boat, just about a six footer is all, but lots of teeth.

When I had Plywood, I ran two wires on hand Gurdies with no poles or floats and I think my best day was 30 Silvers and 3 Chinook, that was after throwing back at least twice that many wild ones. Pretty fun for my buddy and I who were used to coming back in after 4 fish. That and going up the shallow rivers in jet boats to fish are my favorites now a days, not that I've done either for a few years. Did make it out of Tillamook bay once this year.

Alumaweld is really making some nice Ocean boats these days, and they seem to be the only ones you can depend on being around through the tough times. I've known one of the guys over there for years, they build them and sell them and warrant them.

I've fished on North Rivers boats, 19, 21 and 23ft boats, all open boats with tiller handle pumps, they are great, the 21 is the perfect size and width, but they are banko, like so many other.

Here's a picture of a nice fishing boat, and since we're so far off track I thought I'd mention, it could have an IDI in it.

I'm really jealous of the Salmon fishing. I haven't done that in thirty years. My grandfather never had a boat, but he was a avid Salmon fisher, even snagged a few trophies along the way. He's smoke 'em up for all our holiday gatherings, that and oysters he got off his sister in laws beach. I really miss the NW, but hey.... nuttin wrong with living in the worlds best climate either.

That fisher looks a little big for an IDI or even two. Better off with a pair of 8V92's, if she's a single, then I'd go with a 12V92 turbo'd and a 3 or 4:1 tranny. Pull net all day long and not worry a wit about anything but catching!

 

[oldmisterbill]

" some days I get out there and in the Ocean where it's calmer and I'm shaking like a leaf and loving it."

Boy that says a lot. I remember being out in some baaaadd weather. That day the discussion went along these lines.

"mother nature is angry today-she could take us in the bat of an eye - Scary!" "Yes but it sure is something to see-beautiful what she can throw at us - Makes me nervous but I love it" "shur does I still enjoy it too "

 

[CaptTom]

" some days I get out there and in the Ocean where it's calmer and I'm shaking like a leaf and loving it."

Boy that says a lot. I remember being out in some baaaadd weather. That day the discussion went along these lines.

"mother nature is angry today-she could take us in the bat of an eye - Scary!" "Yes but it sure is something to see-beautiful what she can throw at us - Makes me nervous but I love it" "shur does I still enjoy it too "

I should have put this as my signature when questioned about what it's like to be a professional sailor:

"Being a sailor is filled with hours upon days and months of utter boredom, followed with moments of shear terror!"

 

[BigRigTech]

Ain't that the truth...The boat I fished on was the " Mary Teresa" named after my great grandmother and my grandmother....35ft wooden boat, well made with a 14ft beam....We headed out one night around 10pm to work our gillnets for 3-4 days....Our gear was fishing about 70 miles offshore so it was about a 9-10hr steam...We got to the mouth of Shad Bay - 3 miles from our wharf - and it was rough as a ******* but a clear night with a big moon...We were going to turn around and head in until morning but a good friend was a little farther out (aka the "Desperado") and he said it was better out in the deeper water so we kept going...About 2hrs into our steam I was laying in my bunk wide awake - it was too damn rough to sleep. All I remember hearing was my uncle yell " hold on!!!" through the galley door and I could hear the old 453 detroit really howling for all she was worth...The next thing I knew I was standing on my feet in my bunk!...and then I was kissing the galley roof before I was slammed into the bunk again........I can't say for sure how big the roge wave was but when we broke through the top of it and crashed into the gully behind it our prop came out of the water for a second or two.....We then proceed to make the dangerous turn for home and get the jesus out of there.......That old wooden boat made one awful sound when she smashed into the next wave but thank our lucky stars the old girl was built with Juniper planks and oak timbers.

 

[CaptTom]

Ain't that the truth...The boat I fished on was the " Mary Teresa" named after my great grandmother and my grandmother....35ft wooden boat, well made with a 14ft beam....We headed out one night around 10pm to work our gillnets for 3-4 days....Our gear was fishing about 70 miles offshore so it was about a 9-10hr steam...We got to the mouth of Shad Bay - 3 miles from our wharf - and it was rough as a ******* but a clear night with a big moon...We were going to turn around and head in until morning but a good friend was a little farther out (aka the "Desperado") and he said it was better out in the deeper water so we kept going...About 2hrs into our steam I was laying in my bunk wide awake - it was too damn rough to sleep. All I remember hearing was my uncle yell " hold on!!!" through the galley door and I could hear the old 453 detroit really howling for all she was worth...The next thing I knew I was standing on my feet in my bunk!...and then I was kissing the galley roof before I was slammed into the bunk again........I can't say for sure how big the roge wave was but when we broke through the top of it and crashed into the gully behind it our prop came out of the water for a second or two.....We then proceed to make the dangerous turn for home and get the jesus out of there.......That old wooden boat made one awful sound when she smashed into the next wave but thank our lucky stars the old girl was built with Juniper planks and oak timbers.

That's an awesome story!