Banka-style boat

I own a 79' all-wood Banka-syle boat common in the Philippines. We had it built from the ground up basically following the local customs for construction and materials. I cannot go into the details a lot but may be able to answer some questions about it.

Common practice here is to use old truck engines to power the boat, in our case it is an Isuzu diesel engine, 6-cylinder, turbo-charged, 370HP with a transmission. What the locals do is hard mount the engine to the hull, don't install a muffler, nor do any sort of sound dampening.

My questions are:
1. What sort of engine mount should I install (assuming I should)? Right now I think after a few years all the copper nails will rattle out ;~) I thought maybe using four Vetus LMX series Flexible Engine Mounts plus one more for the transmission. A special bracket would have to be fabricated to single-mount the transmission.
2. Any recommendations for sound dampening? The engine is inside a large room with lots of ventilation but the back is wide open. My captain essentially sits right in the path of 100 decibel+ noise - he will be deaf before he is 40. Again this is common practice but I feel for the guy. I thought closing up the opening but still leave an air path and installing some sort of foam inside the room.
3. Is it at all possible to run two alternators off of the engine? I had a small battery, inverter and AC outlets installed for auxiliary power. The main batteries are being charged by the existing alternator. My guess is I cannot just wire the new battery to this system? I do not want to use the main batteries for the inverter in case someone forgets to turn the inverter off...bummer to be stranded because of a dead battery.
4. The local mechanic here apparently knows how to instal a good muffler so I will let him do this. Apparently it involves water as part of the muffler. Eh?

Sorry for the long post. I hope someone has some good suggestions. I will keep at my research and try to learn the best methods for mounting, dampening, mufflers, and alternators. Thanks for any help!

 

Sounds like a non marine engine. Truck engine. Since it has no water cooled exhaust manifold the engine produces very much heat. If you covered the engine with a motor box you would trap the heat. Any sound shield engine box would need plenty of ventilation.

Perhaps its possible to fit a second alternator...it depends on what the front end of the engine looks like. Alternators can also be fit on the rear of the engine...driven by the prop shaft when the engine is in forward.
You can also use one alternator to charge two battery banks.

Why not take a picture of the boat, engine installation, prop shaft stuffing box.

Difficult to understand what you have.

 

There are several solutions but as said by Michael you have to send pics...

 

I will search thru my pics and post them.

 

Hi Muckdiver,
Trucks have engine mounts, mufflers, and sound insulation. If you are already using a truck , why not use more of it?
The parts may not be ideal, but better than nothing.
What sort of cooling system are you using?
Water pumped through the heat exchanger can be run along the tail pipe on its way out.
You can run as many alternators as you like provided you can rig them to a pulley.
Best Wishes,
Adam

 

My unscientific guess would be to do this. Put the engine in a wooden box. Put styrofoam over the box, add another wooden box over the styrofoam.

For the muffler, yes that would be really good too, put that in an insulated box too. Probably the bigger the muffler the better.

 

In boats I have seen around here that have repurposed truck engines the muffler and exhaust stack are piped straight up . The trick is to remember not to grab the pipe as a hand hold since they are hot...

 

Thanks everyone. I will post pics but need to take some. All the ones I have don't give a good perspective of the engine. And most are during construction.

My captain and mechanic bought the engine in Cebu, I never saw it before it arrived at the boat (can you say ouch...about 100 guys muscling a truck engine down the beach about 300 feet, what a sight). Anyway the truck was already long gone by the time we bought the engine. We can get the parts though so buying stock truck mounts may be OK but I worry they won't work all that well in a boat? I mean aren't there are a lot of other forces involved besides just jammin down the road? I assumed I would have to buy marine engine mounts.

Cooling for the engine are a pair of pipes run along the outside of the hull for about 30~40' below water line.

Great news on the additional alternator! I will have the mechanic mount one.

I am also thinking of doing some sort of heat exchanger to heat a 50 gallon drum of fresh water for a shower. I figure I can introduce this easily with a little piping.

 

It all sounds logical. Local materials and the local way of doing things.

Hot water from the engine is nice.

Marine engine mounts are good because they are adjustable when aligning the engine. Of course this could also be done with shims and home made mounts .

What is the transmission ?

 

Very good question. I am trying to determine what it is. I looked for markings last time without luck but will do a more thorough search when I take pictures.

 

Hi Muckdiver,
I have driven a few Isuzu trucks, they either have some sort of Eaton Fuller Roadranger 15 or 18 speed, or an Isuzu gearbox. Will your boat be changing gear? The road rangers are an aquired art to shift gear without alot of crunching.
You could use engine water to heat your shower, or the exhaust pipe. Wrap a coil of copper pipe around the tail pipe or make a sleeve.
How far do you want to go away from the local design? At one end of the spectrum you have a hard mount with no muffler, and at the other a fully marinised diesel with bells and whistles. The truck engine mounts are designed to handle a 50 tonne rig hammering an African gravel road at 60mph. Obviously marine mounts would be better.
With regards to the alternators, I would like to add, you can run as many as you like, provided you understand the current and use the correct wiring coming out of them.

Cheers,
Adam

 

Pictures of our Banka (Laya)

I figured that it would be easier to post them on my Facebook and share a link than trying to post them to this forum.

https://www.facebook.com/media/set/?set=a.3837536195591.122862.1793585631&type=1&l=e3eadcaab2

The engine is an Isuzu 6WA1 with a 15-speed transmission Model MJD7R. The captain only uses 3rd gear and reverse.

 

Hi muckdiver,
You have a very beautiful boat, and you live in a very pleasant part of the world.
Looking at your photos I am not surprised to hear that all of the boat captains are deaf.
There are certainly some very interesting engineering solutions going on in there!
I have driven alot of trucks with that engine, but never that gearbox. Frankly I am shocked no engine or gearbox mounts are used, and that there is no sound insulation.
Why does the engine room need windows?
I am sure that if you found some way to insulate it and mount the motor on rubber, sailing her will be a much more enjoyable experience for everyone involved.
Best Wishes,
Adam

 

Windows were just to let light in, they will be double-paned plex to help with sound. I am having it dry-docked in a month and the boat builder will add a sound baffle to close up the compartment and reroute the air out the back. This will muffle some sound. Then I am going to have fiberglas-covered foam installed inside the compartment which should help some too. Then...in goes engine mounts (based on responses in this forum it does not seem to matter much what I use so will purchase marine-grade mounts) and a muffler. Whew these things should make a big difference.

I liked your idea of the heated water tank and already talked with the captain and hopefully this can go in too with all the other mods.

It is odd how the local captains just put up with the noise, it's pretty loud (100+ decibels minimum). Anyway I am going to buck the trends here and add the necessary sound deadening.

I am curious about the transmission though with the captain only using 3rd gear. I assume the transmission goes gears 1-3 in 5 steps or gears 1-5 in 3 steps? Anyway is there a way to tell whether this is 3rd, 6th, 9th, 12th or 15th gear? And reverse, only one speed right? Considering the adage "if you can't find it grind it" this gear he is using will fail eventually. How does he access say 4th or 5th? Is there another gear lever that just was not put in to access these gears?

 

Hi muckdiver,
I think you will need a mount for the gearbox as well, if you only fix mounts to the engine I think the angle iron on the gearbox will snap.
I looked up that gearbox, I could not find much about it. A roadranger, for example, has four gears on the gear stick, a high low range box, and an overdrive splitter. So you have 16 forward gears, and then two more crawler gears, plus a possibility of four reverse ratios! The two other ranges are controlled by two air switches on the lever.
That box should have at least 8 gears and two reverse. I guess it is synchromesh.
You should find another lever or two of some sort on the gearbox, play with those and you will soon see which is high and low. Some boxes you can only split each gear in high ratio.
Confused? Think of a four wheel drive with high low range, and then an overdrive like an old MG.
Are you using the clutch? If not just turn off the motor in between shifting.
Good Luck,
Adam