My first RIB, a sinking Avon SR6

[ChristerSS]

Hello all!



I really need some advice, so hope I came to the right place!



I just got my first RIB, an Avon SR6, a drunken auction bid, anyway, here we are, I have a RIB!


Im not sure about the age of the vessel, all i know its an Avon SR6 judging the drawings and info I found online.





Main issue is, I think the boat is not floating correct.



How tall is the transom supposed to sit in the water?



When I first tested it, it had partially blocked flooding hull, so it was really heavy after a while, and would not drain due to the block.
No idea what previous owned had tried to do, as it was blocked off with a plate, but had a 12mm hole in it.



So i removed the partial block to leave the hole for the flooding hull open, and atlest it drains well now, boat is easy to plane after driving at speed for a while and just stopping for a moment
But does feel very sluggish when been sitting still, but i guess that is the whole point of it.



But when sitting for longer period, half an hour, it sinks so low that top of transom is at water level, was conserning with so much water in the boat and engine going so close to water.



Is it supposed to be like this? is this boat worth repairing?


I did notice there is some ROT and water ingress in the lower part of the transom, however I do not see any sign of flexing when pulling on the engine, seems like very study boats, is this a huge consern?





Engine is 150 E-tec.




Thanks!



Best regards
Chris.

[ChristerSS]

Forgot to add some pictures.

[Oliver_ribfan]

Congrats to your SR6, you bought a very seaworthy and robust RIB! I hope you enjoy it!

You can determine the building year by the last 2 digits of the serial number. Most Seariders have their serial number plate on the starboard side of the transom outside slightly above the water line.

The transom of the SR6 is generally not very high by design.
Because of the low transom they tend to drive wet. The tubes in your pics touch the water which is not that suspicious to me because of the flooding hull. That could be ok.


However as you say you feel there is water coming in:
1. Did you check for leaks at the elephant trunks or where the tubes are glued to the hull and transom?
2. Where your metal box is most SR6 usually have hatches to get access to the stern bilge chamber. As you have a flooding hull your SR6 will have 2 bilges left and right from the flooding hull tunnel. Is there maybe water coming in after 30 minutes as you describe? It should be completely dry if everything is correct.
3. The flooding hull tank sits under the console with a 1-inch vent hose that ends somewhere within the console through a metal feedthrough. This hose tends to age and get leaky. In front of your flooding hull tank is your 3rd bilge. Some SR6 collect water there coming in through the vent hose either from deck or from flooding hull side. Difficult to check but worth checking.
4. Close to the tubes on each side under deck you will find a small chamber, maybe 25cm wide running maybe 3m long from stern to where the lifting eyelets sit. just air, no foam in it if original. Some SR6 collect water here. There are small drain ports accessible from the stern. Open them and see if water comes out.

The transom and deck is made of plywood and the hull is polyester in most cases. Definitely repairable! Very inviting to DIY-boatbuilders!

[ChristerSS]

Thanks for the good info Oliver!


Behind my metal box there is access panelt on stadboard side, and this bilge area does fill with water, I can feel a small hole inside the flooding hull tunnel to both sides biles at the rear, so maybe this is part of the issue.



I think my plan going forward to test the boat a bit more is just to block off the flooding hull properly, by a plate that has a drain hole, and then do another sea trail and see how much water is coming in then.




Becouse on my last test now I almost flooded my engine, its defeneflty not right as it is now.

[Oliver_ribfan]

Hi Christer,

great that you found it!

The previous owner might have closed the flooding hull and used the 10cm / 4" hole only for draining the bilge by setting additional holes through the tunnel walls.

Oatey sells a round red plastic plug that matches perfectly if you want a non permanent solution: Oatey 33403.
Plumbers use it to close 10cm holes and it fits fine.

If you are looking for more SR6 owners I recommend you to join the "Avon Searider Owners" group on Facebook.

[ChristerSS]

Sounds good 😊




Any idea what model year this could be?

[Oliver_ribfan]

I am confused by the I-A. Not sure. Despite from that I would guess '82 but definitely not sure about it.
The orange looks like tangerine orange which would point to made before '99 if it is the original color tone.

The Facebook group might be the right spot to get a reliable answer.