Lost Gasket on the outside of saildrive

[cabin boy]

I had the boat lifted on Sealift at Gosport on Friday and noticed the gasket on the outside of the hull where the saildrive comes out has come off again!!!
The guy on the Sealift unit said he has seen some boats pack the whole out with sikaflex and not worry about the gasket, has anyone tried that? and if so was it successful.

 

[Tranona]

Stick a new one on properly. Not difficult. If properly attached they stay there for years.

 

[snowleopard]

The don't keep water out and are only there for streamlining. If you clean the area thoroughly and stick a new one on with Sikaflex it will stay stuck. (not sure which type of Sikaflex - ask your engine supplier.

 

[cabin boy]

the one last year was stuck on with silalex by a professional so I tought there must be a better way, maybe not.

 

[Racecruiser]

My previous boat had the same problem and the recommended Volvo adhesive failed which was pretty galling when you think what a detached leading edge must do for water flow under the hull. I got some strong two pack adhesive, cleaned the surfaces as best I could and whacked that on - worked perfectly!

Current boat has a shaft and folding prop which I think I prefer.

 

[wiggy]

If you don't replace it you surely run the risk of getting lots off weed a crustacians on the seal which must be bad for it.

 

[raggy]

I have replaced a good few of them and have found properly done sika to be the best but no matter what you do it can still fall off in a matter weeks.
However I dont think there is any real need for them other than stream lining. The growth gets behind anyway as its not watertight.

 

[scottie]

It also stops UV rays being reflected back to the diaphragm

No this is the 2nd and try leaving a pair of rubber boots in sunlight.

One of the few authentic cases of diaphragm failure occurred this way in the middle east .

 

[Sans Bateau]

For starters, lets kill the idea of filling the hole with Sikaflex, that is the most stupid idea I have heard for a long time, whoever suggested that does not know anything about the subject.

For the last 10 or so years I have always used Evostick. A 'marine' impact adhesive is only going to differ in price. The most important thing in sticking the outer gasket in place is preparation. Like many jobs skimp on the prep and pay later. The area where the gasket is to be placed must be scrupulously clean. The gel coat must be keyed and no signs of old glue or antifoul. The new gasket must be degreased and keyed with course production (sand paper) paper. Then follow to the letter the instructions on the tin, yes the tin, dont try and save money with a tube, use a tin, you'll get it onto the surfaces quicker.

The only problem you will ever encounter using Evostick, if the job is done properly, is getting the old one off when you need to!

Apart from fairing the hull, the outer gasket protects the inner diaphragm from UV. Not such a huge problem in UK waters but can be in the Med.

 

[Sans Bateau]

It also stops UV rays being reflected back to the diaphragm

No this is the 2nd and try leaving a pair of rubber boots in sunlight.

One of the few authentic cases of diaphragm failure occurred this way in the middle east .

As I typed!

 

[jordanbasset]

Ours started peeling off 2 years ago and we used silkaflex to stick it back on, still good as of lift out in October.

 

[AIDY]

as others have said the key is the prep.... abrade both mating surfaces.... and use a seam roller.

 

[bigwow]

For starters, lets kill the idea of filling the hole with Sikaflex, that is the most stupid idea I have heard for a long time, whoever suggested that does not know anything about the subject.

For the last 10 or so years I have always used Evostick. A 'marine' impact adhesive is only going to differ in price. The most important thing in sticking the outer gasket in place is preparation. Like many jobs skimp on the prep and pay later. The area where the gasket is to be placed must be scrupulously clean. The gel coat must be keyed and no signs of old glue or antifoul. The new gasket must be degreased and keyed with course production (sand paper) paper. Then follow to the letter the instructions on the tin, yes the tin, dont try and save money with a tube, use a tin, you'll get it onto the surfaces quicker.

The only problem you will ever encounter using Evostick, if the job is done properly, is getting the old one off when you need to!

Apart from fairing the hull, the outer gasket protects the inner diaphragm from UV. Not such a huge problem in UK waters but can be in the Med.

+1
Bostick contact adhesive is just as good. When stuck on give it a good roll over with a fibreglass roller or wallpaper seam roller.

 

[TeamSpirit]

Had a couple of failures but never lost the gaiter, tried to repair at the sea lift when in Cowes to refix with Evostick but failed again soon after and then did the job properly with marine adhesive (from Marineware). It hasnt moved in two years. Just make sure you prepared the surface well, use a seam roller to ensure good contact with hull and no air bubbles.

 

[johnphilip]

Bisonite

I had the boat lifted on Sealift at Gosport on Friday and noticed the gasket on the outside of the hull where the saildrive comes out has come off again!!!
The guy on the Sealift unit said he has seen some boats pack the whole out with sikaflex and not worry about the gasket, has anyone tried that? and if so was it successful.

The neoprene around our Saildrive started to lift and 5 seasons ago we were advised by Volvo agents to use Bisonite two part, available in local chandlery and has held firm since then and still looks good.
http://www.bison.net/en/products/647-2-components-adhesives/product/2269-power-adhesive-bisonite/