Mechanics Explained: Back to Basics

Best regards to everyone.

Since my problem doesn't really relate to car issues, I tried to reach out to H. Reiner via private message to ask for help. For some reason, it didn't work; either private messages are blocked, or I'm doing something wrong.
Okay, I bought an AFN engine, a 1.9 TDI with 110 horsepower, manufactured in 1997.
I want to marineize it for a small boat with a length of 5.10 meters.
Later, I unfortunately discovered that it was an electronically controlled engine with a VP37 fuel injection pump and a VTG turbocharger (Garrett VNT 15).
Completing the system with electronics is very complicated and expensive for me, so I would like to try converting it to a mechanical cable control system.
A specialized workshop (fuel injection pump service) would perform the repair by bypassing the quantity control mechanism and potentially replacing the housing. However, they require data for calibration with the injectors, as they only repair mechanically controlled fuel injection pumps. They have also mentioned a potential loss of power, but are unsure how much.
With a continuous power output of 75-80 horsepower and a short-term power reserve of 10%, I would be perfectly satisfied.
A planing boat only needs full power (4000 RPM) until it gets up on its plane, which takes about 20-30 seconds. After that, it can maintain cruising speed at around 3000 RPM. In Croatia, there are no exhaust emission tests for boats, so the EGR valve might become clogged.
The question remains: what to do with the turbocharger? Should it be removed, replaced with a non-regulated or wastegate version, have a simpler control system built, be linked to the throttle, or something even better? I fear that completely eliminating it would cause too significant a drop in power and torque. Furthermore, boat engines typically use water cooling (which lacks natural airflow), but this could potentially be addressed with a fan or similar device. A water-cooled intercooler would probably also be recommended.

Since the engine is in very good condition (70,000 km), I would only part with it out of necessity.
Does anyone have any helpful tips on that?
I am very grateful for any good advice or other assistance.
Best regards,
I'm sorry, but I can't translate 'Sreser' because it doesn't appear to be a word in either German or English. It might be a typo, an abbreviation, or a term specific to a particular field. Could you please provide more context or clarify the spelling?

Oops...

That sounds like work.

In principle, converting to a mechanical fuel distributor pump and a wastegate turbocharger would not be a problem, as there are corresponding TDI engines available.
You can get a rough idea by looking at older turbo diesel engines. I also remember seeing a link somewhere that described this conversion (probably on a plant oil or VW bus website, if I recall correctly).

Cooling becomes more difficult. If you want to cool the engine with seawater, you absolutely need a heat exchanger. Otherwise, a standard car radiator would also work, provided it has sufficient airflow or is forced-air cooled. A water-cooled turbocharger is recommended depending on the available space (due to fire risk).
You might even be able to do without the charge air cooler, depending on your performance requirements. However, if it's running with seawater, it must be designed for that purpose; otherwise, you could experience very unpleasant surprises down the line.

You should be aware that a TDI engine with such modifications will not operate on the typical power curve, and therefore the power delivery may not be quite as smooth.

CU Gremlin.

Hi Sreser,

What's so exciting about electronics?
I would search on eBay or similar platforms for a suitable speed limiter, immobilizer (possibly as a combined unit), ignition switch with reading coil, and a wiring harness for the engine. Also, you'll need a matching pedal with a sensor, and that should be mostly it. I would consider converting everything to a purely mechanical system to be rather cumbersome.

The electronics are definitely not seawater-resistant in the long term.
At Marine, EVERYTHING – and I mean absolutely everything – that has to do with electricity must be seawater-proof. Even the smallest connector -> EXPENSIVE.

And it gets really bad when your engine fails just five miles offshore, simply because water has gotten into the speed sensor.

Something like that only makes sense for boats of a certain size, and when you have a real engine room that is properly sealed to the outside.

CU Gremlin.

Then, you could finally find a use for the countless plastic containers that almost every woman gets talked into buying at some point.
Seriously, I didn't realize that electronics are such a critical factor for boats. Isn't it enough if the components are splash-proof? This applies to the motor and its associated electronics.
It shouldn't be producing any water anyway. I guess the issue is probably more about the salt content of the water, right?

Isn't it enough if the components are splash-proof? Including the motor and electronics.
It shouldn't be getting any water anyway. I guess the issue is probably more about the salt content of the water, right?

'That's right, water definitely shouldn't get in there. However, it almost never works on smaller boats because the engine is often crammed into a tight space. Eventually, the bilge becomes leaky (if you even have one), and then the boat starts to fill with water. Heat exchangers are rare, and often, for convenience, the intake for fresh air comes through the open hatch (because nobody wants to verschandeln the air filter again).'

Saltwater is corrosive, and you won't be able to prevent water splashes anyway. You also need to consider bad weather conditions and potential for skidding.
In the automotive sector, it's not nearly as bad. There's no constant exposure to salt (even in winter). In marine applications, you even have to be careful about using metals. Simply hanging a lubricant from a car into the water won't work; it will fail very quickly. Different metals (aluminum, copper, iron) can also cause significant problems. Marine engines that are directly cooled with seawater, for example, have sacrificial anodes in the cooling system.

'I would definitely prefer a fully mechanical TDI engine over any kind of stupid electrical problem that could shut down the machine and which I wouldn't be able to fix at sea.'
Without a throttle position sensor or boost pressure sensor, there's simply no power output.
I've long wondered what people sometimes experience on the street due to water leaks or cable breaks.

While we're at it, the fuel tank really needs to be absolutely watertight. A TDI engine is extremely sensitive to water in the fuel, especially seawater.
Even small amounts can permanently damage the fuel injection pump and valves.

CU Gremlin.

PS: Tupperware containers are amazing CLICK.
It was my idea, taken from real life. Martin Perscheid implemented it perfectly (proudly).

Hi,

Fundamentally, a TDI engine is not that different from a naturally aspirated diesel engine like the AAZ; it's just potentially more durable, which isn't necessarily a bad thing.

So, wouldn't it be simpler to convert the injection system from an AAZ engine or one of the 1.6 TD engines to a turbo diesel (TD) configuration, and either replace the turbocharger or modify its control mechanically so that it can be controlled with a pressure sensor? The engine is intended to run at a relatively constant speed, which means you can essentially regulate the boost pressure with a simple control system.

Wie schnell faehrt so ein Gleitboot eigentlich mit 110 PS? 30 Knoten? Or more?

Best regards,

Jan.

Some early-generation T4 models have a mechanical TDI engine. Therefore, there should be plenty of parts available for replacement and modifications.

Jan6K wrote:

How fast does a planing boat with 110 horsepower actually go?

30 knots? Or more? }
Hi Jan,

It probably achieves a speed of at least 50 knots, or even more, when flying level.
Don't hit me, it hurts, ouch ouch...

With mechanical control, the mass airflow sensor (MAF) also becomes unnecessary. Very practical.

Regards,
mcgregg

Hi,

Quote:

It probably achieves a speed of at least 50 knots, or even more, when flying level.

Tstss... 50 knots is only about 90 km/h... in terms of air resistance, a boat like that is actually better on a trailer than a caravan.

I've never tried it (it's illegal and too dangerous for the Ibiza's chassis), but based on my feeling, the Ibiza with a trailer should be able to reach at least 140...150 km/h, probably close to 160 km/h if you push it hard in 4th gear.

No... my question was definitely serious. I can roughly imagine what 110 horsepower does to a car on land, but I have no idea what it would do on water.

Best regards,

Jan.

Enjoy your meal! / Have a good lunch!

I believe Bernd Jäger is modifying the mechanics of TDI engines for T3 vans intended for desert use.

http://www.syncro-bernd-jaeger.de/

Vintage with pressure vessel is also an option, and it's used in some applications, for example, here:

http://www.poeltech.de/prg/

The turbocharger is set to "high boost" as a default and the driver adjusts it to "low" using the control knob.
I can't explain it any better than this.

Hi, Jockel.

Hello,
Thank you to everyone who responded to my post.
I will answer the questions briefly.
I hope my boat will be able to travel between 22 and 26 knots, although that depends on the load etc. I am aware of the problems with the cooling system.
The electronics, as mentioned in my previous correspondence, are complex and expensive, but above all, susceptible to damage from salty air and condensation (they should be encapsulated in resin).
The best solution for my problem seems to be replacing the fuel injection pump with injectors and the turbocharger with corresponding components from a mechanically controlled engine, perhaps one with around 90 horsepower, like an AAZ (hopefully these can be easily installed, as the engine blocks and cylinder heads are compatible).
Can someone help me find the information I need regarding the cars (year of manufacture, type) and the exact specifications of the equipment that might be suitable?

Best regards,

It seems like a less complicated approach to cast the control unit in a box of artificial resin and replace the mass airflow sensor with a dummy circuit that is also cast together with the control unit.

So, as sensors, you are now only left with things like needle lift sensors, crankshaft angle sensors, boost pressure sensors, and coolant temperature sensors.

If you can also create a hermetically sealed connection for the sensors and cable lugs locally, for example using heat-shrink tubing with hot glue, then there should be no more problems.

There's definitely a saltwater-resistant solution for the 'gas pedal,' such as using an analog proximity sensor or a Hall effect sensor with a magnet instead of the mechanical potentiometer.

So, as sensors, you are now left with only things like throttle position sensors, crankshaft angle sensors, boost pressure sensors, and coolant temperature sensors.

If you can also create a hermetically sealed connection for the sensors and cable lugs locally, for example using heat-shrink tubing with hot glue, then there should be no more problems.


I see the problem right THERE... and if the crankshaft position sensor fails, you're really in trouble, literally .

I find it significantly easier to install a mechanical pump.

I am an electrician, and I know why I distrust this nonsense .

CU Gremlin.

Gremlin wrote:

I am an electrician, and I know why I distrust this thing.

that was good - even if you might find yourself getting into a bit of trouble while saying it...