Trojan Boat Forum

My 16,000 lb (loaded weight) Trojan Internationmal is lift kept.

Prior to the engine refit the entire engine room was painted and the old raw water seacocks and wooden backing plates were replaced.

The new backing plates are marine grade plywood, a bit larger than the factory plates and they were installed with the new scoops/seacocks and 3M's 5200 sealant between the backing plates and the painted hull liner. (yes, this vessel has no structural wood in the stringers and each hull compartment has a full liner)

One of the bunkson the lift has been warping ever so slowly to the point where the sea strainer scoop for the port side through hull was actually resting on the bunk. The scoop was supporting a great deal of the weight of the boat. Since this happened on the port side, the condition was unknown until I happened to notice the wood through hull backing plate had pulled away from the hull liner at the top side and about 1/3 down the two sides closest to the top. The 5200 and paint had seperated from the hull liner. I measured a 3/4" gap at the top (outboard side) of the plate with the boat still on the lift, resting on the thru hull scoop. The bottom of the backing plate is closer to the stringer and did not seperate.

A kayak ride around the port side of the boat showed the scoop resting on the bunk and an airgap for several feet forward and aft of the through hull to the boat lift bunk.

A good bit of the weight in the middle of the boat, engine room and equipment was being supported by this raw water scoop, seacock and backing plate.

I lowered the lift and with the boat still above the submerged lift, checked for water leakage and any other damage. There are no leaks whatsoever, however a bit of the paint is cracked and a tiny gel coat stress crack is apparent just forward of the through hull fitting.

once in the water with the stress taken off the strainer, the hull relaxed and the top 1/3 of the backing plate moved back to the hull with the gap immediately reduced to 1/4". I believed that over the next few hours this would continue so I forced some new 5200 into the gap, assuming that once the pressure of all that weight concentrated in one spot was removed that the backing plate would become more compressed to the hull liner, sandwiching in the fresh 5200. Subsequently checking her just now (14 hours after setting her back into the water) I can see that some of the 5200 has "squirted" out from behind the backing plate, confirming that with the pressure removed, everything is flattening out. The 5200 is not yet completely dry so this "squirting" may continue today.

I believe the backing plate bonded to the paint in the bilge as opposed to directly to the liner, thus making it easier for the plate to lift off the liner when the weight of the boat was concentrated on the raw water intake scoop.

I plan on examining the outside hull area very carefully after handling the repair of the boat lift. If I find any damage, off she goes to the hard for repair.

The question is, assuming there is no apparent damage or stress cracks in the hull, and the seacock, backing plate area continues to remain dry, is it necessary for me to remove the seacock, fittings, scoop and backing plate and re-do everything?

I am thankful that this is a solid glass hull with no balsa core to be compromised.

Thank you all in advance for your comments and advice.

RWS



1983 Trojan International 10 Meter Twin Yanmar 315 Turbodiesels

I would remove the thru hull and insp to hole just to be sure but manly to reseal the thru hull on the bottom

RWS, I've been following the replies on the BE forum. Hopefully you'll find an answer and solution if needed. Hopefully there is no structual damage other than some small gel coat and paint cracks.

Your engine room is flawless! Could only wish mine looked that clean.
Are those safety lamps in your engine room of metal housings? And are you using 120 or 12 volt bulbs. I am thinking of installing lighting in my engine room with similar and using 12 volt bulbs, wired to dedicated 12 volt source.

Thanks,

Jamie

Stripermann2 wrote:RWS, I've been following the replies on the BE forum. Hopefully you'll find an answer and solution if needed. Hopefully there is no structual damage other than some small gel coat and paint cracks.

Your engine room is flawless! Could only wish mine looked that clean.
Are those safety lamps in your engine room of metal housings? And are you using 120 or 12 volt bulbs. I am thinking of installing lighting in my engine room with similar and using 12 volt bulbs, wired to dedicated 12 volt source.

Thanks,

Jamie

I'll second that Jamie .... I believe the word "flawless" does best describe it's appearence. Look's better then new RWS

Tanks guys,

As you can see from the other website, the engine room was pretty nasty when we did the repower.

Interestingly, the oak wooden blocks that Trojan used to mount the Crusader adjustable motor mounts were brittle and cracked. The originl owner actually laid some fiberglass mat over one in an effort to hold it together.

The explosion proof lights are available from WW Grainger. You can run 120 volt or 12v. We're running 12v, same as the factory setup. We installed 5 additional lights to the factory one and put them on seperate switches as running them all six at a time could be a fairly heavy load on the house battery.

Working around these in line 6 cylinc=der engines is a breeze compred to the 454's except for the height. With the lights, doing any service work like zincs or filters, even impellers is more of a pleasant task as compared to the chore it used to be.

We also relocated the fresh water pump to a starboard bracket located out of the wayand the big change was building a starboard shelf on the starboard side next to the vacuum tank and up against the bulkhead forthe replacement CruiseAir unit.

Once I get the lift bunk issue addressed I can get her out of the water and get a better look on the outside of the hull. That little stress crack on the inside liner has me concerned.

Plus I don't like the idea that that wood filler block actually did seperate from the inside of the hull liner surface.

As she sits in the water now, still no leaks and the hull has now relaxed with the plate now (aparently) just about back to where it was.

RWS

I agree with Paul, if it were mine I would remove the thru hole and re-bed the intake, for piece of mind. Out of curiosity where is the BE forum?

http://www.boatered.com

A good overall website where peoplewith a passion for boating share info and ask questions.

I have learned a great deal at that website.

RWS