Buying a 1985 Nacra 5.0 (most likely)
Where you able to fix the leaking hull.
I have a similar problem got about 3 gallons of water after sailing a few hours in one of the hulls but
don't see anywhere it could have got in.
I did capsize, but both ports seemed to be sealed.
I don't understand how you pressurize the hulls with air.
Do you put the air hose in one of the ports (how tight should the seal be for the air hose)and then brush with soapy water?
The boat is super fast and fun but I am now regretting getting it due to this problem. The hulls seem solid.
Is this a problem with all old nacra 5.0 and 5.7 boats?

Here is a thread with information on pressure testing your hulls.
https://www.thebeachcats.com/index.php?module=forums&func=viewtopic&topic=14404
H18m
p16
Venture15

Almost all older Cats leak somewhat.
Put a cap of silicone sealant on each rivet head on the tramp tracks. Leave one rivet unsealed so pressure equalizes with temperatures changes.
I think I have a post on the above link. There should be a live link in that post.
Or, go to Albums- Technical. Look for Pressure Tester
I put a short album on an easy, & safe pressure tester you can build for a $.
Get a bucket of soapy water, pump a bit of pressure into the hull & mop soapy water, you will find the Leah quickly. Don’t forget to check the drain plugs, that’s where ours was leaking.
Those hulls are solid fibreglass, easy to repair if it’s holed.
Edited by Edchris177 on Sep 08, 2021 - 10:01 PM.
E C Hilliard
Nacra 5.7
Bombardier Invitation
Did your plugs leaked or the area around the plugs? rivets hull.
Fiberglass work does not seem easy unless you have the know how and tools.
im hopint the boat leaked from the ports after the capsize but ill test it later using the ballon pump.
thanks for the advise again.
Did the hulls on new 5.7 leak in 1984.
anyone know where to find details on the constructiom of the original boat?
curious on how they were built. how many people were needed to produce a hull etc?
Edchris this site should pay you to be a member.
Once again your advise has helped me. I found the leak on my hull immediately
I used a balloon pump in the drain and soapy water. The soap water was making bubbles out of the forward port
I am pretty happy and this is all I can find. It will be pretty easy to seal the port area with silicone. Ill take it out again and see how much water i bring back this weekend.
Thanks again!
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