Heat absorbing sheets under tri cabin bunks

Bob Giaier · Post by **Bob Giaier** » Sun Jun 20, 2010 7:23 pm

We are planning to launch our 73 Tri Cabin next Saturday. We bought her last October after she had been stored in a barn for 13 years. We worked on her all winter pulled her out into the sun last week end and washed her down.

My question has to do with the engine covers - aft bunks. The boat has the original sound/heat absorbing material attached to the covers around the engines (or bunks). This material has deteriated and is crumbling. It reminds me of the black material used on houses back in 70's between the brick and studs.

Has anyone out there replaced the heat absorbing material on their tri cabin?

Thanks in advance for any help.

k9th · Post by **k9th** » Sun Jun 20, 2010 9:24 pm

Mine tri-cabin is a '79 and the engines are located mid-ship under the salon floor but they still have sound and heat protection. Mine is a thick dense foam that is mounted to the removable floorboards and they are not original. They work good. I can run for hours and when we stop there is no noticeable heat transferred through the floor.

rickalan35 · Post by **rickalan35** » Sun Jun 20, 2010 10:59 pm

Bob,

I'm embarrassed to admit that my '72 Tri Cabin still has that same damn stuff attached to the engine covers.

I plan on replacing it but haven't gotten around to it yet. Perhaps your post will get me started.

One thing I particularly don't like about that stuff is how close it sits to the carb air intakes.

I vacuum debris from those very old tech, disintegrating pieces of heat resistant material that you are describing off of both engines and surrounding bilge areas each spring and then wipe the engines down with detergent. That usually takes care of it.

When the marina winterizes my engines each fall and then gets the boat ready in the spring, the marina staff have a habit of banging those engine covers down a little hard, thus loosening the material that's glued to the back.

I purchased silver heat resistant sheets from my chandelry a couple of years ago and those sheets are still sitting in my garage.

The new sheets are a lot thinner that the old tech stuff and supposedly, they work very well. I haven't gotten around to scraping the old stuff off and then replacing it with the new stuff. Probably a winter project.

By the way, my buddy has installed two silent DC exhaust fans with shallow intake scoops located directly over the engines (one over each engine) which he turns on after running the engines, if he's sleeping on the boat. The two exhaust fans do a great job of drawing off that hot air and pulling in cooler air across.

Bob, my advice is that if it can wait until winter, you should wait till then and take those marine plywood covers home and scrape off the old stuff and then re-glue modern heat resistant material to the back.

Thanks, Rick

Bob Giaier · Post by **Bob Giaier** » Mon Jun 21, 2010 7:52 pm

Rick, you described my concernn as well with that debre all around the carb intake.

I probably will wait till winter so I can refinish the bunk side of the panels too.

Let's see if annyone out there has a material type source etc...

thx

Big D · Post by **Big D** » Mon Jun 21, 2010 9:49 pm

My vessel is a little older so I may have different stuff (still original). I will eventually replace it but does anyone know if asbestos was ever used in Trojan production?? Does anyone know how to tell if the product has asbestos in it? I would want to take precautions if it does.

rickalan35 · Post by **rickalan35** » Mon Jun 21, 2010 11:04 pm

Big D

My heat resistant material is brown. I sure in heck hope it's not asbestos. I don't think it is.

Asbestos will be grey and will flake off. Don't even try to remove it if you're not certain what it is.

A unique characteristic of asbestos is that it easily breaks down from its visible form into progressively smaller pieces until it is microscopic in size. Asbestos fibers can therefore be in the air and inhaled without the person being aware of their presence.

Although banned around the world it is still mined in Canada and used in the U.S.

I have never heard anything about Trojan Boats having used asbestos in their manufacturing process, although it was definitely used in large ocean liner shipyards as an insulator.

Maybe Bob knows. Comments anyone??

Rick

Big D · Post by **Big D** » Tue Jun 22, 2010 9:20 pm

Thanks for the info Rick. I suspect then that I'm OK. My sheets have a black surface and brown core. They are more like the large droped ceiling panels in composition. I don't even know how fire retardent they are. May take a piece and try it one day.

Bob Giaier · Post by **Bob Giaier** » Wed Jun 23, 2010 9:14 pm

I do agree with BigD, but the asbestos is a really good point. The stuff looks like compressed saw dust. I'm gonna do the burn test too. (not on the boat of coarse)

rickalan35 · Post by **rickalan35** » Thu Jun 24, 2010 12:27 am

Bob, Big D and K9th, I finally bit the bullet this afternoon and went up to the marina and hauled the engine covers off and dragged them out onto the dock.

Lo and behold, my heat insulation material was screw nailed on and not glued like I had somehow managed to assume. I simply unscrewed the stuff off.

The material on my engine covers was definitely that old fiberboard stuff that my Dad called Ten Test. When I was a kid, they started cladding new homes with with this stuff, as a cheap replacement for plywood. It was also called Black Joe here in Ontario.

Somebody was having a bad designer day at the Trojan plant when they came up with the bright idea (or cost savings idea) to use this stuff but at least they didn't use asbestos.

Here is a wikipedia definition for this material:

Impregnated fiberboard has been used as insulative sheathing for years and is known by such names as blackboard, grayboard, or buffaloboard. It can either be structural or non-structural which requires corner bracing. It is constructed of wood, or other plant, fibers which are mixed with binding agents and other materials and compressed together. Many fiberboard products are made using post-consumer recycled fiber.

Fiberboard is primarily used for wall sheathing and floor underlayment. It has a higher R-value than most other wood-based sheathings (approximately 2.4 per inch) and has sound attenuating properties.

Hope my stuff was the same as what you fellas have.

Take care

Rick

Bob Giaier · Post by **Bob Giaier** » Thu Jun 24, 2010 9:59 pm

It's exactly the same as mine. Like I said earlier I also remember this stuff on homes when I was a kid (70's).

I've been thinking of using a Dow Corning real compressed fibre glass insulation that is about 1" thick with a aluminum sheathing. I used it where I work for insulation in an oven application. I know it will be a superior insulator for heat/ sound and the sheathing will also be great to reflect the heat. I'm just not sure how it will handle the moisture......

Sounds like I'm going to call Dow Corning and talk to them about moisture. I'll report back on what I find.

By the way, according to Wikepedia maybe Trojan didn't do too bad. The stuffs still on all our boats after all these years and it sounds like it's a "Green" material. Incredibly ahead of their times for the 70's eh?

rickalan35 · Post by **rickalan35** » Fri Jun 25, 2010 11:22 am

Bob,

Well, you're right. The stuff is still there on our boats all these years later.

Trojan was indeed ahead of their time with these great hulls and teak joinery. Witness the interior of any Chris Craft from the same era. No comparison.

Never had any delamination on my Tricabin thank goodness, but my buddy beside me on the dock has an F32 that had a delamination problem that took a lot of work to fix.

One concern I have is the idea of replacing my heat/insulation substance with anything that is one inch thick again. Maybe there's no way around it.

I have always wished my air intake had a little more room and I have finally provided that now, when I removed the Black Joe. Even half an inch thick might be acceptable. What do you think?

Let us know what Dow Corning says.

Thanks , Rick

Big D · Post by **Big D** » Fri Jun 25, 2010 11:01 pm

Great info guys.

Bob Giaier · Post by **Bob Giaier** » Sun Jun 27, 2010 6:57 pm

Ok Rick,

I did do the burn test. It burns pretty slow and smooth. Evenn smells pretty good like insence.

I agree about the air intake being located pretty high. no matter what material I use, I will be cutting it a few inches wider than the spark arester, so the extra thickness my not matter. Could take a few to get to Dow Corning, but I 'll let you know.

Bob

rickalan35 · Post by **rickalan35** » Sun Jun 27, 2010 11:21 pm

Guys,

Well, after removing the old heat absorbing ten test, I re-installed the plywood and unfortunately, it now lays right on top of the flame arrestors.

It turns out that the former ten test layer actually laid on top of the cross members and thus raised the plywood half an inch, up off the flame arrestors of my Ford blocks.

I figure now that I will probably buy one inch strips of "whatever" (probably cedar) and over lay these strips onto the bunk cross members, in order to raise the whole bed base to a higher level and thereby allow the plywood some space above the arrestors.

Other ideas??

R

Bob Giaier · Post by **Bob Giaier** » Mon Jun 28, 2010 9:23 pm

Dang, you're right. I guess I would try the same thing with 1/2 inch 3/4 marine ply. Cedar sounds good too. (I'll remember that one)