Forespar Marelon ball valves -seacock replacement

[pagoda]

I'm basically new to this game - and working through several seacocks the surveyor described as stiff...
Anyway, I have read through quite a few threads on the merits of ball valves / gate valves / Blakes style valves etc. And all sorts of arguments about alloys. Almost too much info /forums/images/graemlins/confused.gif
I also came across the Marelon range of valves, which look pretty effective. They exist as seacocks -complete with skin fittings, and also as discrete valves with BSP & other connections.
If I have a couple of existing seacock valves (BSP threads) needing replaced, I would prefer not to have to dismantle the skin fittings unless I have to.
Is it acceptable technically to replace only the faulty valve mechanism by the equivalent Forespar valve -with the same threaded connections?
Do I have to ditch otherwise sound skin fittings as well?
I'm sure somebody else has had the same idea- any thoughts appreciated.
Graeme

 

[MIKE_MCKIE]

I have fitted Marelon sea valves & very happy with them. However you can only buy the whole thing, including the skin fitting. As far as I know you cannot use them with metal skin fittings due to thread size. In any case the warranty is void is you do not use the whole thing. Cannot see a problem doing a complete swap, I just enlarged the existing hole & in they went. One good thing, I never need to worry about electrolysis again, and ease of use is the dogs whatsits.
My advice would be to go for it.

 

[saltwater_gypsy]

You can replace most ball and gate valves without changing the skin fitting. Blakes valves are different since the skin fitting is an integral part of the valve.
The removal of the old valve can involve a certain amount of heat and brutality and it is best to have someone on the outside of the hull to prevent rotation of the skin fitting. (some have a slot or flat to help you do this).In truth, I would prefer to re-seat the skin fitting.
Marelon valves look good and are widely used on aluminium boats. I think they are not allowed in proximity to the engine because of the possibility of melting in a fire but someone will be along in a minute to clarify this.
The main thing is to get good quality marine products and not cheap Chinese brass!!!!!!!

 

[oakum]

I put one on the "for sale" forum - (before this tread started) - been thinking about it for ages - how coincidental is that ?