concerns about osmosis in marina

During a recent conversation with a marine surveyor. He was concerned about how many boats have long term grp hull problems in the marina. It is advisable to take boats out every year for some time to prevent this problem becoming serious and expensive.

Freshwater is somewhat worse than salt water for Osmosis.

The quality of the gel/resin/polyester makes a big difference as well as the build quality. Some boats suffer from it more tha others, if you leave your boat in all year every year then is just a matter of time. That said even boat that are on the hard over the winter can still suffer from it.

No boat has ever sunk from Osmosis, it is repairable, if you have high moisture content and a few bubbles (if you burst them they smell like venegar) you can treat them with and epoxy filler.. but would be advised to leave your boat out over the winter... and shouldnt get much worse too quickly...If its very bad then a gel peel, dry out an epoxy treatment will be expensive.

I have seen some old Bayliners with very bad pox, as well as a few Hardy's and Cruisers.. modern boats shouldnt suffer in the same way. That said there are a lot of boats at Cameron that come out of the water very rarely, and I bet there are quite a few older boats that have bad osmosis.

A lot of people wouldnt touch boats with Osmosis, but if its not too bad its a good way to get a cheap boat if it doesent put you off... a boat with Osmosis is similar to trying to sell a house that has flooded once..

Best Regards

Craig

My last bayliner 285 had no osmosis and it had been in the water for 3 years before I hauled her out to dry and anti-foul. I agree that quite a few larger boats at the marina are now overdue a lift out to dry. I shear to think what the hulls must be like?

John

Another concern you should have is galvanic corrossion.. especially if you have shore power plugged in 24/7 and/or a boat next to you does.. or has a shore power fault..

I have came accross quite a few boats on the Loch with Zinc anodes instead of magnesuim... fitting the wrong anode can cause severe corrossion to outdrives and props.... if you have the wrong anode just check the corrosion on your power trim rams.. esp the volvo ones where the stainless hydraulic fitting screws into the ram.. if its leaking.. bet its the threads in the alloy that have corroded away..

Also faulty battery chargers and shore power installations can make your underwater gear attractive to stray currents..

My recent boat has a knackered prop due to galvanic leaching due to wrong anode.. and corrosion to one of the skin fittings.. spent most of the weekend changing them..

As well as making sure you have the right anodes and they are properly bonded, a galavanic isloator on your shore power earth connections is a sound investment, will also make your anodes last longer... typical price for one is around £80
on fleabay

http://cgi.ebay.co.uk/Sterling-Power-Galvanic-Isolator-ProSveE-ZS30A_W0QQitemZ180348199088QQcmdZViewItemQQptZUK_CarsParts_Vehicles_BoatEquipment_Accessories_SM?hash=item29fd9720b0&_trksid=p3286.c0.m14

I allways fit one to all my boats... pays for itself... anodes arent cheap

Best Regards

Craig

I had a 26ft Bayliner surveyed 2012 at CH
it was riddled underneath with blisters surveyor reckoned 5-8k+ to fix
complete removal dry out and re gelcoat required to get back to normal
hadnt been out of water in years and below waterline it showed
also had a dodgy CE conformity plate which couldnt be verified either
i walked away as owner wouldnt budge on price either
i see some other poor sod has bought it since its still at marina in water
Surveys are essential and pay for themselves i would advise everyone
to get one only cost me £300 and saved me a heap of trouble
Waster1111