Putting TDI in a boat ...

shakescreek

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18'6" welded aluminum jetboat with pd160, gtb2056vl, and tuning by rub87, 2003 chev blazer with bhw swap, 2000 jetta alh with gtd1752 vrk, .240 injectors, 11mm pump, fmic, 6 spd manual
"I would like to see how the coolant circuit works."

I have 2 aluminum pipes passing through the transom and welded in place, one above the other. The heat exchanger is clamped to the to pipes on the outside of the transom. If you go to the member area in the picture galleries and go to shakescreek and look at picture #9 of the rear of the boat you can see the heat exchanger if you look between the jet and the ex pipe towards the far side of the transom. It is the vertical pipe looking thing. Mine is homemade but you can buy commercial made ones. It is just a bundle of small tubes(mine are about 5/16ths) running longitudinally through a large aluminum pipe (think mine is 4"id). The coolant from the engine flows in the top of the large pipe, flows around the small tubes and out the bottom of the large pipe. The jet pump has two 3/4" nipples on the front of it to supply cooling water and one is connected to the bottom of the heat exchanger forcing cold river water through the tubes to cool the engine coolant. The other nipple feeds water to the intercooler and oil cooler. If you look at pic #7 you can see the expansion tank just to the left of the red plastic ecu cover on the inside of the transom. The coolant hoses are not connected to it in that picture as the boat is partially apart right now but the rear of the engine is about 1' from the transom so the coolant flows from the outlet at the back of the cyl. head to the expansion tank, through the ex tank into the top of the heat exchanger, out the bottom of the heat exchanger back through the transom to the inlet at the thermostat & water pump on the left front of the engine block. Hope I explained that clearly, any more questions just ask.
Laurie.
 

dx1001

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Nov 13, 2015
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iowa, usa
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2003 jetta
TDI powered boat!

OK- How did this work out??? I think a pair of 1.9's would be great! Chip them, of course to get more horsepower & add heat exchanger so saltwater or freshwater ready... Start with twin volvo & retrofit TDI engines...
How hard can it be assuming the drive can be hooked up to mercruiser it's all good, right?
 

shakescreek

Veteran Member
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Oct 14, 2005
Location
B.C. Canada
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18'6" welded aluminum jetboat with pd160, gtb2056vl, and tuning by rub87, 2003 chev blazer with bhw swap, 2000 jetta alh with gtd1752 vrk, .240 injectors, 11mm pump, fmic, 6 spd manual
Not sure who your question is directed at but my tdi jetboat has worked out great. Have about 2300 hours on it and still running great. As i have no road access where I live it is pretty much my daily driver. Use it to go to town for mail and groceries, and make weekly trips 100 miles downriver for work, as I commercial salmon fish just above the border with alaska.
 

jmodge

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Greenville, MI
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2001 alh Jetta, RC2 w/.205's 5speed daily summer commuter and 2000 alh Jetta 5spd swap, 2" lift, hitch, stage 3 TDtuning w/.216's winter cruiser, 1996 Tacoma ALh
Not sure who your question is directed at but my tdi jetboat has worked out great. Have about 2300 hours on it and still running great. As i have no road access where I live it is pretty much my daily driver. Use it to go to town for mail and groceries, and make weekly trips 100 miles downriver for work, as I commercial salmon fish just above the border with alaska.
No road access....THAT is #€$&@WILD!
 

shakescreek

Veteran Member
Joined
Oct 14, 2005
Location
B.C. Canada
TDI
18'6" welded aluminum jetboat with pd160, gtb2056vl, and tuning by rub87, 2003 chev blazer with bhw swap, 2000 jetta alh with gtd1752 vrk, .240 injectors, 11mm pump, fmic, 6 spd manual
No road access....THAT is #€$&@WILD!
It's not for everyone but there is no way I'd trade this lifestyle for town life. We're on the Stikine river in northwestern BC, about 40 miles east of the Alaskan border and 150 miles south of the Yukon border. TDI boat is still running well and life is good. That said I'm 67 years old so we will have to look at moving somewhere a little less remote at some point, hopefully that's a decade or so away yet.
 

jmodge

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2001 alh Jetta, RC2 w/.205's 5speed daily summer commuter and 2000 alh Jetta 5spd swap, 2" lift, hitch, stage 3 TDtuning w/.216's winter cruiser, 1996 Tacoma ALh
Sounds like heaven on earth, reminds me of the fella that moved into wild Alaska via bush plane and recorded his journey through building his own home, etc.
So the way I understood your description of the cooling system it’s closed with a heat exchanger outside the transom instead of a radiator and the pump in front of the jet drive supplies cool water to run through the exchangers on the transom, stock TDI oil cooler, water to air intercooler, then back out to the river?
Also wondered what type of jet drive/pump you have. I’m not familiar with the options, but it seems the ones I’ve seen are longer in length than yours
 

shakescreek

Veteran Member
Joined
Oct 14, 2005
Location
B.C. Canada
TDI
18'6" welded aluminum jetboat with pd160, gtb2056vl, and tuning by rub87, 2003 chev blazer with bhw swap, 2000 jetta alh with gtd1752 vrk, .240 injectors, 11mm pump, fmic, 6 spd manual
Sounds like heaven on earth, reminds me of the fella that moved into wild Alaska via bush plane and recorded his journey through building his own home, etc.
So the way I understood your description of the cooling system it’s closed with a heat exchanger outside the transom instead of a radiator and the pump in front of the jet drive supplies cool water to run through the exchangers on the transom, stock TDI oil cooler, water to air intercooler, then back out to the river?
Also wondered what type of jet drive/pump you have. I’m not familiar with the options, but it seems the ones I’ve seen are longer in length than yours
Pump is an American Turbine SD309. There is no separate pump for the cooling water, it is bled off the chamber behind(pressure side) the main impeller that provides the thrust. There are 2 hose barbs on the pump to provide cooling water, one feeds the engine coolant heat exchanger and is dumped overboard after exiting the heat exchanger, the other goes to the intercooler first, then on exiting the intercooler it is fed through the center section of the turbo, and finally through the stock oil cooler and from there exits overboard.
 

jmodge

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2001 alh Jetta, RC2 w/.205's 5speed daily summer commuter and 2000 alh Jetta 5spd swap, 2" lift, hitch, stage 3 TDtuning w/.216's winter cruiser, 1996 Tacoma ALh
Pump is an American Turbine SD309. There is no separate pump for the cooling water, it is bled off the chamber behind(pressure side) the main impeller that provides the thrust. There are 2 hose barbs on the pump to provide cooling water, one feeds the engine coolant heat exchanger and is dumped overboard after exiting the heat exchanger, the other goes to the intercooler first, then on exiting the intercooler it is fed through the center section of the turbo, and finally through the stock oil cooler and from there exits overboard.
Ok, that was a clear explanation, got it. Thanks. I was wondering if you get in larger water than the river. If so, how does a jet drive handle rollers such as in the ocean or a large lake.
Asking in regards to how a jet drive would handle in Lake Michigan.
I’ll have to ask around some marinas also. I’m on an inland lake and don’t see many jet drives, other than PWC’s. But I see a few advantages to them, weight and simplicity being two. My questions about them are how hard weeds would be on them and how they handle swells. I’ve read there are tight tolerances in the turbine so weeds, silt, and stone can be hard on them.
 

PickleRick

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Nov 29, 2017
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Greenville sc
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05 GLS BHW sedan 5 speed conversion. BHW Carver SantaCruz in progress
I don't have any experience personally with a jet drive on the water but I have flipped a boat with one. Came from lake Erie as retirement toy. I got it running again after the owners death and resold to a guy from Ohio who had it back on Erie the following weekend. Olds 455 with Berkeley jet drive. 25 ft Thomson runabout.


Very much a fair weather boat, while an outboard or stern drive would get more bite in the storm/wind driven square great lake waves in the same hull the, the occupants would not be comfortable in either.


Was very popular but fuel back then was much more affordable. Just like jet skis sand and rocks will kill the drive. Also like the jet ski, low speed maneuvering around the docks is tricky, especially in wind or current. Seagrass and seaweed will clogg the intake just as fast as it would on an inboard or outdrive.
 

jmodge

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Greenville, MI
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2001 alh Jetta, RC2 w/.205's 5speed daily summer commuter and 2000 alh Jetta 5spd swap, 2" lift, hitch, stage 3 TDtuning w/.216's winter cruiser, 1996 Tacoma ALh
I don't have any experience personally with a jet drive on the water but I have flipped a boat with one. Came from lake Erie as retirement toy. I got it running again after the owners death and resold to a guy from Ohio who had it back on Erie the following weekend. Olds 455 with Berkeley jet drive. 25 ft Thomson runabout.


Very much a fair weather boat, while an outboard or stern drive would get more bite in the storm/wind driven square great lake waves in the same hull the, the occupants would not be comfortable in either.


Was very popular but fuel back then was much more affordable. Just like jet skis sand and rocks will kill the drive. Also like the jet ski, low speed maneuvering around the docks is tricky, especially in wind or current. Seagrass and seaweed will clogg the intake just as fast as it would on an inboard or outdrive.
I can imagine maneuvering would take some getting used to, no neutral as I understand. Fuel economy I wouldn’t be concerned with, especially with a TDI. As long as the unit is tight, it doesn’t seem like it would be working much harder than turning a stern drive to keep it moving.
I would spend the majority of my time on an inland lake. Occasional Jaunts up and down rivers as well as a few trips into the big lakes. So wear and tear from weeds and silt would be a concern as well as how it worked in swells. I’d hate to be on one of the Great Lakes and find it handle that well.
What did you mean by occupant comfort?
 

jmodge

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2001 alh Jetta, RC2 w/.205's 5speed daily summer commuter and 2000 alh Jetta 5spd swap, 2" lift, hitch, stage 3 TDtuning w/.216's winter cruiser, 1996 Tacoma ALh
I imagine a jet drive would lose maneuverability with less throttle where as a sterndrive with a prop and basically a “rudder” would be significantly better in wind and waves when the boat is forced to slow down
 

PickleRick

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05 GLS BHW sedan 5 speed conversion. BHW Carver SantaCruz in progress
By occupant comfort I mean by the time the waves are high/close enough together to make the drive come out of water you're going to be in conditions that those aboard will not want to be in. Jet drive boats rarely have a Grady white or similar offshore style, ride in 4 ft chop like it's nothing designed hulls.


The Boston whaler rage offered a jet drive set up in small fishing boat, if you want first hand accounts that's a good read up. The general consensus on the hull truth is they hated them. Most Boston whaler boats demand top dollar except their jet drive ones. it's a small hull and a 1.9 should move it well.


Generally speaking a stern leg boat is much faster than the same hull with straight inboards. It's also more efficient. The trade off is a true inboard is more stable in waves. I don't think you'll lose any fuel efficiency with stern drive, you'll likely improve over jet drive.

You can't beat the docking manners/reverse of an oil outboard or stern drive. But for rivers, a jet drive with no prop to hit rocks, would be sweet.
 
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jmodge

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2001 alh Jetta, RC2 w/.205's 5speed daily summer commuter and 2000 alh Jetta 5spd swap, 2" lift, hitch, stage 3 TDtuning w/.216's winter cruiser, 1996 Tacoma ALh
By occupant comfort I mean by the time the waves are high/close enough together to make the drive come out of water you're going to be in conditions that those aboard will not want to be in. Jet drive boats rarely have a Grady white or similar offshore style, ride in 4 ft chop like it's nothing designed hulls.


The Boston whaler rage offered a jet drive set up in small fishing boat, if you want first hand accounts that's a good read up. The general consensus on the hull truth is they hated them. Most Boston whaler boats demand top dollar except their jet drive ones. it's a small hull and a 1.9 should move it well.


Generally speaking a stern leg boat is much faster than the same hull with straight inboards. It's also more efficient. The trade off is a true inboard is more stable in waves. I don't think you'll lose any fuel efficiency with stern drive, you'll likely improve over jet drive.

You can't beat the docking manners/reverse of an oil outboard or stern drive. But for rivers, a jet drive with no prop to hit rocks, would be sweet.
, I get it, Good info. From what I deduce, if I do this a sterndrive would be best for my use, more versatility. My river trips would be mostly occasional easy cruises, not zipping from point A to B, that may terminate in a big lake. Shallow lake waters and occasional trips to a river rule out an inboard for me, and the big lake rules out the jet drive. I've owned outboards and sterndrives, so I'm familiar with them.

I take it at the least you are a boat enthusiast, and possibly a marine mechanic?
 

GTiTDi

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, I get it, Good info. From what I deduce, if I do this a sterndrive would be best for my use, more versatility. My river trips would be mostly occasional easy cruises, not zipping from point A to B, that may terminate in a big lake. Shallow lake waters and occasional trips to a river rule out an inboard for me, and the big lake rules out the jet drive. I've owned outboards and sterndrives, so I'm familiar with them.

I take it at the least you are a boat enthusiast, and possibly a marine mechanic?
The BHW project in his signature would confirm that suspicion. I'd like to see that setup!
 

PickleRick

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The BHW project in his signature would confirm that suspicion. I'd like to see that setup!
I ended up with a BHW powered Toyota 4 runner. I ditched my BHW diesel powered boat project when I found a factory diesel 28 footer on a brand new triaxle trailer for a price I couldn't turn down.


I'm not a marine mechanic, just spend a lot of time on the water.
 

jmodge

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2001 alh Jetta, RC2 w/.205's 5speed daily summer commuter and 2000 alh Jetta 5spd swap, 2" lift, hitch, stage 3 TDtuning w/.216's winter cruiser, 1996 Tacoma ALh
I ended up with a BHW powered Toyota 4 runner. I ditched my BHW diesel powered boat project when I found a factory diesel 28 footer on a brand new triaxle trailer for a price I couldn't turn down

I'm not a marine mechanic, just spend a lot of time on the water.
Is that factory diesel a stern drive? If so, do they cool the exhaust and run it out the prop or uncooled through hull? Water cooled turbo plus intercooled?
 

PickleRick

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05 GLS BHW sedan 5 speed conversion. BHW Carver SantaCruz in progress
It is a bravo 2 mercruiser stern drive. The water comes into the heat exchanger (radiator) and then goes through the aftercooler (intercooler) last but not least it hits the water jacketed turbo before exiting out the exhaust down through the stern drive.

There are zinc inserts in both the turbo and aftercooler to help them last longer before corrosion takes them out.


It was a factory install. That year 2859 Bayliner offered a 5.7, 7.4 or 4.2 diesel. The gassers got the option of a bravo 2 or bravo 3 duo prop. The diesel was only offered with the bravo 2 due to the torque and weight of the 5 ton boat.


You could exit the exhaust through the hull if you wanted, many V8 guys do this for sound/power. You have water spraying into your exhaust so your exhaust pipe is never too hot to touch under normal running conditions.
 

shakescreek

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Oct 14, 2005
Location
B.C. Canada
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18'6" welded aluminum jetboat with pd160, gtb2056vl, and tuning by rub87, 2003 chev blazer with bhw swap, 2000 jetta alh with gtd1752 vrk, .240 injectors, 11mm pump, fmic, 6 spd manual
I take my boat down to saltwater in Alaska occasionally. Usually go about 30 miles out from the mouth of the river for halibut fishing. Handles swells and rollers just fine, but rides pretty rough in shorter sharper waves. I think the hull is what determines the suitability for bigger open water not the type of drive, but most jetdrives are in hulls designed to run shallow, so deadrises in the 6 to 12 degree range which makes them pretty rough riding. In my boat trying to stay on step in even 1 foot chop can just about rattle your teeth out. Seaweed can also be a problem as it will collect on the intake grate and clog it, usually not a problem if you can stay on step through patches of seaweed but will clog quickly if trying to go slowly through a patch of weeds. Mostly it's the intake grate that a problem, whatever gets through the grate is usually just chewed up by the impeller and goes right through, although occasionally something can get stuck on a impeller blade and require opening the cleanout hatch on the jet and reaching in with your hand to pull the offending piece out of the impeller. Silt is a non issue and rocks will not be picked up by the jet if you running on step unless you're running so shallow the hull starts hitting the bottom. The most common time to pick up rocks is backing of a beach with the back of the boat in too shallow water, as the reverse deflector directs the water from the jetdrive nozzle back under the hull which stirs up rocks on the bottom causing the intake to pick them up. The other common time to pick up rocks in the drive is if you are going slowly off step in less than about 2 feet of water and you give it throttle to get up on step. The suction of the jet under power combined with the stern of the boat squatting well getting on step will vacuum up whatever is on the bottom. Once on step I can run in 5 inches of water over fine gravel and get nothing in the jet, as the forward speed moves the intake ahead faster than the stones can lift off the bottom. Steering with a jet is no problem, just requires a little get used to as they have no rudder and require thust for steering. Blips of throttle well going slowly work well, and don't chop the throttle in the middle of a high speed turn.
 

2.0TDmark

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2012 Jetta TDI
I take my boat down to saltwater in Alaska occasionally. Usually go about 30 miles out from the mouth of the river for halibut fishing. Handles swells and rollers just fine, but rides pretty rough in shorter sharper waves. I think the hull is what determines the suitability for bigger open water not the type of drive, but most jetdrives are in hulls designed to run shallow, so deadrises in the 6 to 12 degree range which makes them pretty rough riding. In my boat trying to stay on step in even 1 foot chop can just about rattle your teeth out. Seaweed can also be a problem as it will collect on the intake grate and clog it, usually not a problem if you can stay on step through patches of seaweed but will clog quickly if trying to go slowly through a patch of weeds. Mostly it's the intake grate that a problem, whatever gets through the grate is usually just chewed up by the impeller and goes right through, although occasionally something can get stuck on a impeller blade and require opening the cleanout hatch on the jet and reaching in with your hand to pull the offending piece out of the impeller. Silt is a non issue and rocks will not be picked up by the jet if you running on step unless you're running so shallow the hull starts hitting the bottom. The most common time to pick up rocks is backing of a beach with the back of the boat in too shallow water, as the reverse deflector directs the water from the jetdrive nozzle back under the hull which stirs up rocks on the bottom causing the intake to pick them up. The other common time to pick up rocks in the drive is if you are going slowly off step in less than about 2 feet of water and you give it throttle to get up on step. The suction of the jet under power combined with the stern of the boat squatting well getting on step will vacuum up whatever is on the bottom. Once on step I can run in 5 inches of water over fine gravel and get nothing in the jet, as the forward speed moves the intake ahead faster than the stones can lift off the bottom. Steering with a jet is no problem, just requires a little get used to as they have no rudder and require thust for steering. Blips of throttle well going slowly work well, and don't chop the throttle in the middle of a high speed turn.
What kind of fuel mileage do you get with the TDI engine?
 

shakescreek

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Oct 14, 2005
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B.C. Canada
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18'6" welded aluminum jetboat with pd160, gtb2056vl, and tuning by rub87, 2003 chev blazer with bhw swap, 2000 jetta alh with gtd1752 vrk, .240 injectors, 11mm pump, fmic, 6 spd manual
Typically 2 to 3 gph depending on load and speed, which is about 10 to 15 mpg. Usual cruise speed is about 30 mph. Those numbers are imperial gallons so would be a little more converted to us gallons
 
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