Blakes' seacocks.

[rex_seadog]

Blakes\' seacocks.

When sailing well-heeled we experience problems with water backing up the heads outlet pipe and overflowing from the bowl. With the Delta's virtually non-existent bilges this water soon finds its way throughout the boat! This happens despite religiously closing off the seacock - a Blakes' 1 1/2 inch. Before anyone comments about looping the hose well above the waterline, on our boat there is insufficient space to easily do this.

Anyway, a couple of weeks ago with the boat out of the water we decided to bite the bullet and remove the seacock (following excellent advice in a thread from about last March) with a view to refurbishment or renewal. I had always thought that tuning the handle through 90 degrees from the 'on' position closed the valve. However, on close inspection I realised that a further 10-15 degrees is necessary before it is completely closed. Is this the cause of all our problems? I'm now tempted to grind in the cone (as we do every year) and refit the seacock with Sikaflex and new bolts (three of the old ones sheared off with very little force). What are your thoughts? I note that the latest Blakes's seacocks are fitted with grease nipples - how much difference does this modification make? I have always greased each season with a waterproof grease (red and quite sticky) sold for trailer bearings. Is this OK or should I use the Blakes' product?

 

[tome]

Re: Blakes\' seacocks.

Just been through all this myself! Boat went back in on Tuesday.

1 Blakes type seacocks are closed when the handle lies against the hose, not at 90 degrees. They are open when the handle is opposite the hose. If you examine the aperture in the cone you'll see this. However, doubt if this was your problem as it's pretty effectively closed at 90 degrees (take a look).

2 You shouldn't need to grind the cones every season - inspect it for wear and only grind if necessary. I reground 1 seacock this season.

3 The heads outlet is particularly prone to leaks through pitting caused by bacterial erosion. This is usually a result of closing the seacock with 'stuff' still in the hose, or pumping with the seacock closed or both. I renewed my heads oulet this season because it was badly pitted.

4 The new Blakes type has a grease nipple which allows you to grease it without dismantling, ie you can service it afloat. It has a slightly different cover plate with a detent to provide positive open and closed positions. The arm can be removed and inverted if you can only swing the arm in a particular arc. They are expensive at around 100 quid but it sounds like you will probably need to replace yours, especially since you are vulnerable to flooding. Could you not have it leak tested? You'd hate to put the boat back in and find you still have a problem.

5 The Blakes grease is designed for the job - it's a pale green concoction and costs about 5 pounds for a tub which should last for years. Couldn't comment on whether it's any better than trailer grease, but it's what I use.

Finally, don't overtighten the cover plate. You should just tighten enough to provide light friction on the handle otherwise you'll dislodge the grease. Use the locknuts to lock off when you're done. These can be a devil to reach and I adapted a 5/8 in spanner by shortening the handle as it was the only way to get access on mine.

 

[Guest]

Re: Blakes\' seacocks.

had exactly the same experience with the seacocks on the bilge pumps of my boat. i think you most probably have found the problem.

i have also had the bacterial corrosion referred to above. if you are suffering from the same, you might like to consider a modern glass re-inforced nypon seacock - which will be corrosion proof. if its strong enough for log and depth sounder fittings, then it ought to be for sea cocks surely?

anybody had any contrary experience of nylon skin fittings?

 

[tome]

Re: Blakes\' seacocks.

Yes! A friend nearly lost his boat when the nylon gas locker drain outlet (just above WL) skin fitting snapped on his mooring. There'd been a bit of a blow and enough water had come in to put the hole on the WL. Probably snapped due to loose gear in cockpit locker, but he examined it and found it had gone brittle. I had the same boat with the same arrangement and checked mine - it was also brittle. Since then I've replaced all nylon with bronze fittings, just done the same on my new boat.

That said, the log and depth sounder are nylon but I don't like it and keep an eye on condition.

 

[spark]

Plastic seacocks.

After much deliberation I have just invested in a full set of Forespar Marelon seacocks. They seem to be popular in the US and claim to exceed ABYC recommendations.

The material is "a formulation of glass reinforced dupont zytel" rather than nylon and they appear to be robustly made and claim to be non-corrosive, non-conductive, fire resistant (to what extent is not given), and resistant to bilge cleaners/diesel/oil/etc.

They come as a integral unit (skin-fitting - valve - hosetail) and cost less than the same in bronze (www.asap-supplies.com).

I hope nobody out there has a horror story for me....?

 

[jeanne]

Blakes\' seacocks bolts.

Interested in the bolts which Rex said, in the first post, sheared easily. I had two out of three bolts shear, with the seacock holding on by one bolt and the force of habit. When I phoned for replacements, the guy asked how long they had been fitted, and when I said 8 years, he agreed that ' that was about how long they lasted' This shocked me, as I think of my boat as a long term project, and not something where you strip it down and start again every 8 [ 7? 6?]years ! At the very least , a limited service life should be a matter to be drawn to the owners attention in the initial sales literature. I know about crevice corrosion in stainless steel, but I fitted s.s. bolts, rather than Blakes 'bronze' ones, on the grounds that I can see if corrosion like that is happening by withdrawing a bolt now and then, rather than taking another ticket in a lottery, i.e. will I remember to change them before they sink me.

 

[Plum]

Re: Blakes\' seacocks bolts.

I was going to fit Blakes' Seacocks 4 years ago but noticed in their literature that they guarantee the seacock for 10 years, but not the bolts they supply to fit it!!!

 

[rex_seadog]

Re: Blakes\' seacocks.

Thanks for all the replies. Having found out how relatively simple the seacock is to remove I think I will now try it for another season but making sure that it is fully turned off. I understand from the March thread that the four replacement bolts will cost me about £24 (!!!) but hopefully they will not shear if I have to remove the seacock again next autumn. The reason we re-ground each season was to try to remove an area of pitting that presumably had been caused by the bacterial corrosion referred to. We now seem to have finally ground out this patch.
The money (hopefully) saved will be put towards a new loo as our existing Par Brydon always seeps a little water when used. Despite grovelling around on hands and knees on many occasions I'm damned if I can find the source of the problem. I changed all the seals about 4 years ago only to find another leak from a cracked elbow. By the time I'd replaced that I was half way to the cost a new loo. So this time that's the way I'm going plus new hoses. I won't say this too loudly but compared to other yottie stuff the price of marine loos seem quite reasonable.