Trojan Boat Forum

Several years ago, I did a complete restoration on a '70s vintage Kohler generator and installed it in my F-26. This was a great addition to the boat since it means that while on the hook I can make hot water, run the AC, charge the batteries, etc. As a mater of fact, this generator does everything that I ask it to except "BE QUIET". The actual exhaust noise is not the problem, since the Vernalift muffler and water separator keep it to a minimum, its the mechanical noise from the generator itself. I insulated the bottom side of the floors and hatches but that only helped a bit. I then noticed that most late model generators are housed in enclosures with sound proofing to keep them quiet, this got me thinking that it was time for another project.

Although this project is not completed as of yet, I thought I'd share how I'm going about it and where the project is at today.

I realized right away that a few things would have to be addressed. First, due to the tight spaces in the F-26 this enclosure would have to be removable without tools for quick and easy access to the pumps, rudder gear and stuffing box behind/under the enclosure in the event of an emergency. Secondly, it has to allow for adequate ventilation to get the heat out. Thirdly, if this thing is going to be a part of my boat it has to look good. Below is a picture of the area that I have to work in.



I started the project with a tape measure and some sheets of cardboard. I made a four sided box with a separate lid. Covering the entire generator took up too much room and really restricted access to the pumps and rudder so I made it narrower. This cleared an access path for me and also took care of the ventilation problem. The back where the exhaust manifold and breather are is wide open as well as the bottom of the enclosure. The next trick was to try to get this thing out thru the generator hatch. To Do this I had to make the enclosure a three piece assembly.

Once satisfied with the cardboard model, I made drawings and sent them into a local fab shop and had them water jet cut, bend and weld the pieces as required. The material is 1/8" 6061 aluminum sheet. Below are some pictures.







The tabs used to join the pieces together are made from the same material as the enclosure panels themselves. The receiver is made three pieces, two spacers and a bridge. The male tab is a single piece sanded a little thinner to provide an easy slip fit. Edges that meet are capped with rubber edging ti prevent rattling.





Buckles are used to hold it all together. The first piece to go into the boat was the forward & port walls. This piece is screwed directly to the fuel tank cradle and is not intended to be removed without tools. This is what supports the other pieces.



Clearance between the enclosure and the breather was minimal and needs to be increased. Instead of cutting greater clearance in the panel which would make this area even narrower and weaker than it already is, I needed to find another option. I remembered that I had a parts generator at home that still had its breather cap on it. I decided that I would take this one and cut out a clearance notch into it, weld a plate into it on an angle to fill the hole and then paint it so that it looks good. (yes, body work Jeff) Below is a picture of the breather marked for cutting. Although it looks nasty now, it wont when I'm done. The entire generator looked like this before restoration.



This next pictures show the enclosure assembled with the rear deck off.





This last picture shows the enclosure in place with the rear deck also in place. Unsnap the buckles and the lid and removable side section come out thru the hatch opening easily.



Well that's about it for now. I've removed the enclosure from the boat and plan on getting it to the powder coater's shop sometime this week for a nice white finish. When I get it back I will be lining it with fire retardant sound proofong before re-installing it. I'm hoping to do the breather within the next few weeks.

I'll post some more pictures of the job when complete. Unfortunately I won't know the results of my efforts until next spring when she goes back in the water but I'm keeping my fingers crossed for good results. And for those of you wondering, I have about $300 into the job not including the powder coat which is really not that bad.

OK, The first picture is good but I can't seem to get the other ones going.

Any suggestions?

OK Problem solved thanks to Heiner.

thanks for the interesting thread.

i'm all over this and can't wait to see the pictures!

RWS

Make sure it has good ventilation . Remember Air cools the generator end .

Hi Paul, you are welcome

--
Greetings - Heiner

DID YOU DO THAT BEAUTIFUL SHEETMETAL WORK? I went to a magnet high school and studied aircraft sheetmetal. Work like that is practically pornographic to me. I presume the future work includes sound-attenuating material on the inside? Did you replace the vibration dampers? The elastomer can harden over time, reducing their isolating effectiveness. Please do show us the completed project.

Thanks Heiner, that seems to have taken care of the problem.

P-Dogg, the motor mounts are still soft and in good condition.

This is why Paul's boat look like it does. Everything is perfect.

prowlersfish wrote:Make sure it has good ventilation . Remember Air cools the generator end .

Right you are Paul. On this unit, the electrical portion generator side draws its air from the bottom and blows it back out thru the bottom. I designed the enclosure with this in mind so it has no bottom. The only thing under the generator is a small drip tray directly under the engine.

Doing a fine Job . I have thought of making on for mine using fiber glass .

Nice job Paul. Well thought out. Is there anything affected by ambient temps that you need to consider; ie choke adjustment, or path the fuel line is taking re heat soak/vapour lock?

Big D wrote:Nice job Paul. Well thought out. Is there anything affected by ambient temps that you need to consider; ie choke adjustment, or path the fuel line is taking re heat soak/vapour lock?

Good observations Big D but I think that it should all be good. The electric choke, fuel line, pump and carb are all located in the area at the back of the enclosure which remains open to the engine bay.

I'm anxious to see how many dB the sound level in the cockpit will be reduced by. Spring sure seems a long way off.

Somehow things like that seem to make the winter go by slower eh? Sounds like (pun!) you've covered (pun!) pretty much everything. How well it's isolated from surrounding hardware and structures that would tranfer noise and vibration will play a big roll also.

Nice job! Looks like it should do what you want. Cant wait to see the finished project.

Big D wrote: How well it's isolated from surrounding hardware and structures that would tranfer noise and vibration will play a big roll also.

This makes me wonder how much noise and vibration are transferred to the hull by the hard wall rubber exhaust hoses used on the main engine. I also wonder if it could be reduced by replacing some or all of it with silicone hoses and hump fittings such as those made by Trident.