Installing a trunk into the transom of DR 490

[two stroke mick]

I am thinking of installing a trunk into my Valiant DR 490. I have removed the "one way valve" and the hole that has been drilled in the transom for this valve is 50mm. I am thinking of filling this hole and re coring up to 70-75mm to install a trunk.

Can any one think of any problems that this may cause structural or otherwise. But I dont think that increaing the hole from 50mm to 75mm should have any structural effect on the transom. The transom is rated for 80 hp and I have a 60hp on it, the transom is rated for 175 kg and the engine is 109-112 kg. your thoughts please

An photos of the trunk arrangement espicall the draw cord system would be appraicated

TSM

[mike-stgt]

Take the machine and drill your hole.
Mike

[9D280]

2- stroke,

Only possible problem I could see here is - is your one way valve dead centre (and in front of the outboard? if so you'll need to drill a new hole. It won't be a problem - the hole is drilled right down at the join with the deck You could could in theory hold the transom to the floor with a piano hinge (structurally, I'm not taking watertightness into account here!) My boat has two 70mm holes, and the transom's as solid as the day it was built (and that wasn't yesterday!) As a thought, if you do need to re- site it, if you are careful, you could use the 70mm Core as a plug for the 50mm hole you are filling in. Alternatively, just leave the 50mm alone & put one of those compressive bungs in it It is more likely to help drainage out the water, as trunks tend to fold & seal themselves.

As for the draw cord, that will depend on a) how easy you want access b) how often you plan on using it. There is a thread on here about it. Standard trick is a jam cleat on the inside of the transom. I've led mine forward and use a bit of bungee to make sure it drops when i release it - means i can raise / lower them from the helm position. if you take this option, the actual cord route will depend on your boat's setup.

[prairie tuber]

Mick,

This thread might have some info that is useful to you;

http://rib.net/forum/showthread.php?t=28000

[two stroke mick]

Yesterday I filled the "one way valve" and cored out a 70mm hole at the location of the one way valve. This then took the trunk unit I purchased from the rib shop. I think it looks quite good.

TSM

[davis]

any photos mick, as I was thinking of doing the same

[two stroke mick]

Hi davis.

I will put up a photo in the next few days. I have just the 68mm section of pipe installed so far.

I removed the old one way valve and got a tablet box that fitted it. I filled the box with fibreglass resin to make a solid plug. The resin plug slipped out of the tablet box as I did not sand the inside of the box before I poured in the resin thus it had nothing to key to. I used superglue to hold the resin plug i the tablet box and superglued the box into the 50mm hole. I then placed a timber boad at the back of the transom so as to prevent burst through. I drilled out the hole with a 70mm core drill bit. I purchased the trunk off the ribshop 68mm od

If you require any further information let me know.

TSM

[two stroke mick]

Photos as promised