Water under deck in Terhi 415R

[Dr. Jones]

Hi,

 

(I hope it's OK with you guays that I write in English. Please feel free to respond in Norwegian if you prefer.)

 

I have just acquired a wonderful vintage Terhi, the 415R. While restoring it, I removed the swivel seat stands and stearing wheel bracket from the deck to find that the screw holes had not been properly sealed: Water came out of the holes. If I blew compressed air into one hole, water bubbled out of another.

 

Now I’m curious if this means that the entire hull is flooded, or just a narrow compartment under the deck.

 

From reading the forum, I know that many people in here have owned 415R's. Does any of you have cross section drawings or any understanding on the construction of the boat? Does water directly under the deck mean that the boat is no longer non-sinkable, or are there many separate compartments in the hull that could still be intact?

 

I really hope you can help me out!

[Kaffelars]

Wish I could help, don't know this particular model, but it could be you indeed have water intrusion into the foam core. Do you have any chance to weigh the boat, to assess the amount of added weight?

 

I have a Terhi BigFun(16ft), and this is constructed with a foam filled hull with two liners(like a open layout), and then there is a third inner liner giving the seats, storage and visible layout. The innerliner deck has maybe 2-3cm. clearance above the two part outer hull. There is a separate drain with extractor for the innerliner, and a bottom plug for draining the inside of the outer hull below a small hatch in the tank compartment.

 

Could be the 415 has only to layers of foam filled ABS.. repairs on this type of constructio material demands different solutions than traditional GRP, instructions and materials can be sourced from Terhi directly or a retailer.

[Dr. Jones]

Thanks for your reply.

 

I decided that the only way to make sure was to drill two 16 mm holes near the critical locations on the deck and examine the foam. And I'm glad I did: The foam turned out to be perfectly dry and firm in both holes!

 

I sealed the holes with glass fibre reenforced G/Flex and are no longer loosing sleep about the problem :-).