Thompson

[Paul eagen]

Hey guys, this is a wealth of info (under statement). I have a 79 Thompson 17.5 foot bow rider. The power plant is a 120 hp 4 cylinder omc. That part of it is in great shape. The floor is starting to rot and I am thinking about redoing it. I know that is probably not the only thing that would be needed so I am just trying to get some info to help me get a budget together. I had a question about the foam under the floor. I know it is probably full of water that is why the boat and trailer weighs 2500 lbs. Will I have to replace it or can i leave it out. I dont know if it is part of the structure or if it is for floatation and does any one know what will happen if I dont put any back in.

 

[Bob_VT]

Re: Thompson

BTW flotation is very light when dry. It is a good idea to replace it and not leave it out.

 

[Yacht Dr.]

Re: Thompson

Hello Paul..

I doubt that the foam is of "structural" value..but without knowing that construction I cant say for sure..

I suggest .. IF you tear your deck up.. then just replace the foam ( encapsulate it with glass ) .

Basically..dont let water get to your foam..

YD.

 

[CheapboatKev]

Re: Thompson

I must say...
This is the first post I have read in a looong time that had an OMC set-up and the motor wasn't the reason for posting!

 

[Paul eagen]

Re: Thompson

Already had that problem but got it fixed. Not the motor though just every thing else out drive , tilt ect.ect. ha ha

 

[rngale]

Re: Thompson

the foam "maybe" a structural part of the boat. Some manufacturers used a 4-5 lb density foam between the floor and the hull to help stiffen the hull and the floor at the same time allowing them to use less layers of fiberglass. If you open the floor up and rmove the fuel tank and you see extra layers of glass under the fuel tank and not the rest of the bottom of the boat then there is a chance that it may be of some structural value.

You can add layers of glass to overcome this problem as well as adding additional bulkheads. but the price difference in the 3lb and the 4 lb foam is cheaper to use the foam than the extra work involved in regalssing the entire bottom of the boat.

 

[Paul eagen]

Re: Thompson

Thanks for your input everyone. I dont know when i will start working on it since it is still ok at the moment. It will make it through this season. I had one spot in the floor, near the back that was very bad so i pulled up that section about 2ft by 1ft. Every thing I can see from that opening and the engine compartment looks very good no rot at all on the stingers or the motor mounts. The foam is alittle wet in some places but not soaked. the only thing I don't like is that the stringers are not fully glassed, it looks like they just capped them with a very heavy fiberglass mat about 3/4 of the way down. Anyway This info in here is great. Good luck on all of your projects. We need to find a way to get rid of that murphy guy for good