Fuel fillers

jwalker · 17 April 2003, 22:18

I could do with your suggestions please guys.
Where have you found the best place to sight a fuel filler for under deck tanks? Bearing in mind ease of filling, slippery deck, diesely fumes while eating the picnic etc., etc.
Ta.
JW.

crazyhorse · 18 April 2003, 00:22

JW we got them set in the transom with filters.I will get you a pic if you want. A mate of mine is saying that a 4 inch Filler is his prefered size So as to take commercial pipe if offshore.

I have also been advised that 2 inch is fine as you also need aprox 50 % for a breather so ideal would be 2 inch with a 1 inch breather pipe.

They recon that 4 inch with a commercial hose could blow your tanks?,Ok if your filling big gals Tanks, but not needed for 2x125g size tanks.Pressure tested at 5 psi.

We have now decided on 2 inch with 1 inch breather pipe Fillers set in the Transom.

Mike Garside · 18 April 2003, 06:20

JW, the original filler point for the single tank on Magellan Alpha was inside the engine box on the forward bulkhead. This was very easy to use and kept mess and fumes away from living areas

The filler pipe opening was also set into a box of it's own where the the breather pipe also led. This meant that any blow back or overfill went into the box and drained back into the filler pipe. This was a good place to store rags as well. It was neat set-up and I liked it a lot. Unfortunately it had to go when I installed the bigger engine and need the space.

Now I have two filler pipes and both are on deck with their vents. They can be messy alongside the commercial fuel barge in Falmouth when there is a bit of a sea running.

Both are 2 inch pipes and one fills fast and the other slowly. The superiority of the fast one is down to the fact that the breather pipe is better. It is short and rises all the way from the tank and there is no chance of a sump blockage at any stage.

With the original breather pipe I have done my best to vent it vertically but it has a levelish stretch in the middle and it gets filled with diesel foam and slows the whole process down.

If I were doing it again from scratch I would go for:

1 the widest, shortest pipes I could install.
2 a closable overflow box with each filler point.

Hope those ideas are of some interest.

jwalker · 18 April 2003, 20:34

Thanks CH & MG.
I don't know anything about the 4" pipe CH. The tanker that delivers my home central heating oil connects via a 60mm thread. It may actually be an old thread because 60mm is almost exactly 2 & 3/8". It's likely that a harbourside tanker would use this connector.

Mike, thanks for you comments. What you used to have is exactly what I was planning but I had a reservation about the bow end of the tank being higher than the stern and, therefore, a large air pocket would form and prevent complete filling. Your tank/deck must have been almost parallel to the water surface. Yes?

Cheers, JW.

crazyhorse · 18 April 2003, 21:11

Eve folks

Each of our tanks have there own seperate fillers and our friends who has 5 tanks and swears by the 4 inch fillers also has seperate fillers for each tank.They are then linked with pumps and a shut off valves and breather for each.If the bow tank wanted to be filled then if filled directly from its own filler, I fail to see how providing the breather works how it will air lock? If your suggesting filling all tanks from a single point other than the higher bow tank, then I fail to see how each tank will fill correctly from a single point as the bow tank is higher?
I would recommend each tank have its own filler and shut off tap and breather.

This my take on the situation if I have missed something out feel free to let me know.

Mike Garside · 19 April 2003, 06:23

JW - a quick pic will cut down on my words...the explanation in the post that follows.

Mike Garside · 19 April 2003, 06:47

Tank 3 was the original. It fills and vents via a pipe that is connected to the aft end of the tank. I have not been able to open up the floor to get at this tank (bad design!) so I am not exactly sure why it is so difficult to fill.

My two new tanks (1 & 2) are linked by a 2" tube and I fill the front one while No 2 vents. It is very quick. However, it would have been better to fill No 1 from the forward end to prevent an air pocket but I have managed to fill almost exactly 400 litres into them and they are supposed to be 200 each, so suspect there is no air pocket.

But I do agree with you. I would put the filler and vents at any obvious high point where the boat lies at rest.

Incidently, tanks 1 and 2 have a feed to the engine from the aft end of two. (Actually there are two feeds from 2 - one from the port side and one from the starboard to take account of the fact that the base of tank two is saddled to take the keelson. The amount of fuel left on either side when the tank is almost empty is my emergency reserve!)

Tank 3 is effectively the day tank and is the only one that has a return. I use this tank until it is less than half full then switch to the forward tanks. When tank 3 is almost refilled by the return I switch back to tank 1 and 2 for the supply.

This has the advantage of keeping the boat trim fairly constant. The downside is that you have to keep an eye on the guage that is attached to tank 3. On one notable occasion soon after I had installed the set up and was sleeping off my French lunch while Mrs G drove me back across the Channel to Falmouth, I had failed to explain it all to her.

I awoke to a furious driver who had eventually spotted the cockpit was awash with diesel fountaining out of the aft tank breather pipe! Grrrr!

Dirk Diggler · 19 April 2003, 09:00

Quote:

Originally posted by Mike Garside
I awoke to a furious driver who had eventually spotted the cockpit was awash with diesel fountaining out of the aft tank breather pipe! Grrrr!

How did that get past the RCD Crazyhorse?

Jonny Fuller · 19 April 2003, 09:37

Mike,
If your tank "straddles" the keel and so needs two outlets to retrieve the fuel in these two seperate areas (when the level drops below the centre hump) if for some reason one of the feeds is a little easier to draw from than the other (which it probably is), this side will empty first and begin to draw air, whilst the other side would still contain fuel, would it not!

crazyhorse · 19 April 2003, 10:49

Well on the RCD question,I believe that both boats havent got RCD catergories for offshore use eg cat B. Mikes was built before 1998 so doesnt need to comply,but should get it quite easily as it will have a very good angle of vanishing stability,but depending on where the first downflooding point is, it may need alteration to the engine box or hull openings, whichever starts to fill first before aprox 5o% of tilt. JW isnt interested in RCD cat B build regs,and even if he were then it is doughtfull if your building withought any regard to them at this stage that it will get a cat B status withought a lot of modifications /changes afterwards and subsequent costs. On the fuel regs for RCD as our builders havnt installed the system yet but have signed a contract,to say that it will comply to the minimum standards required for fuel instalations for offshore use commercialy/work boat code, and RCD,Which includes fire resistant blurb/and pressure testing ect.I dont know exactly what the regs are at this stage for RCD compliance on fuel tanks instalations, but will be doing it in the next three months as far as fuel tanks and breathers and fillers and shut off valves and fire resistance of hoses go. Its a real ball ache complying but in the long term,I am of the belief that it will pay off one day as some of the RCD regs are there to make a boat by design more safer.I MHO

Mike Garside · 19 April 2003, 11:42

Quote:

Originally posted by Jon Fuller
... if for some reason one of the feeds is a little easier to draw from than the other (which it probably is), this side will empty first and begin to draw air, whilst the other side would still contain fuel, would it not!

You are right that when one side of the straddle is empty it would draw air but this isn't a problem because there are taps at the end of each of the pipes where they feed into the common engine supply pipe. I simply close the tap that relates to the empty side and open the tap that gives access to the reserve. Of the 3 taps 2 are always closed.

OK?

crazyhorse · 19 April 2003, 11:50

Ok Mike

Jonny Fuller · 19 April 2003, 19:00

Mike, so how does your fuel return work? and how long does it take to bleed your fuel system when you realise too late and it's drawn air?
This is not criticism, I'm just interested!
When I've rigged multi tank setups that reqiure only one feed, I've run all tanks into a manifold which is lower than all the tanks, an outlet from this feeds the engine, the return runs to the highest tank although it could probably run to any one of them as the manifold would allow them to ballance the small volume involved with the return system.

jwalker · 19 April 2003, 19:03

Mike, thanks, I do follow. My original thoughts were to fit 3 tanks. Only the rear one was to have a filler and the the front tank would vent, via a high part, to the middle one and that vent similarly into the rear one. On filling, the fuel would be pumped from the rear forward to whichever tank required it. The pumps are reversible so fuel could be moved about to trim the boat if necessary. Unless all the tanks are fairly full, of course. Each tank would have a feed and return. These could be selected manually, using 2 off 3 in, 1 out cocks, or selected via solenoid valves. The filling was to be done, as you had suggested, within the engine compartment using a catch funnel to feed any spillage into the filler pipe. However, I'm fairly certain, at rest, the forward tank vent will be higher than the top of the rear tank and it wont fill fully. Likewise the centre tank. The whole system could be turned around and filled from the front but I'd loose the benefit, which you confirmed, of having the fumey/greasey end out of the way. But, you've given me food for thought. Ta.

Did Mrs. G tap you for a new pair of shoes?

CH, the boat is already cat B, but I think DD was winding you up! You gotta keep your eye on him!

OK DD and JF, you've got a new boat. Tell me how you would fuel it.

JW.

Jonny Fuller · 19 April 2003, 19:24

JW,
How many motors, how many tanks? is it a rib or a real one LOL

jwalker · 19 April 2003, 19:32

JF, One motor, 3 tanks and it's a real rib one.

No, lets start from scratch. One inboard diesel motor in a real RIB. How would you do it and why?

JW.

crazyhorse · 19 April 2003, 19:36

On Diggis RCD Quote JW .

I dont believe it is a wind up as I am of the oppinion that there is a lot more to this,than maybe you all realise.

But I shall leave all this tank stuff to the experts,But one little point worth mentioning here is The Hull if it has a rcd cat B Ce mark as is for the hull only, with there own configuration of engine,Tanks,weights ect. fine for them, and a boat purchased from them, but maybe not you as you have a hull only.

This could of been passed with in a outboard configuration or there with there own specified designated inboard, and built to there own spec ,that would of then been put through the tests To show conformaty to RCD cat B compliance.

Unfortunatly this makes doing your own fit out none complient unless it passes the exact same tests as the ones your hull manufacturer homologated for CE marking approval.The cost for the tests are in the region of £2000.There are no credits if a boat fails.

If you check with Them I think they may confirm this, as they are not fitting the boat out themselves,therefore they have no claims Re RCD stability and fit out regs, As you are doing this yourself,and with no disrespect we can all make mistakes.

Good luck with it JW and if you eventually you want any RCD stuff that will give you maybe a chance of complying then feel free to say so.

As you know I am not winging it, as my costs/risks are to high to maybe end up with a offshore rib, that maybe one day I cant go offshore in becouse of maybe a future insurance companys unrealistic demands.

Jonny Fuller · 19 April 2003, 19:52

JW,
as this is a test, I must have the rules laid out to avoid argument.
what style of rib are we talking, ie cabin, open, etc, and are the tanks to be underfloor?, wing, in line, ?

crazyhorse · 19 April 2003, 20:00

This is going to be fun

jwalker · 19 April 2003, 20:11

JF, no test, just picking you brains. But, I'll grade you out of 10 if you would like.

Open 8.5mtr rib, large consol two seats behind the consol and bench seat on front top of engine box. There's a bit of extra height to play with - the floor area between the engine box and the console is to be raised about 150mm. All wiring etc. from motor to consol is to pass through there. The breather pipe(s) could too if necessary. Anchor locker in the bow and storage lockers also at the bow, at each side. So a bit of weight up front.
Tanks to be underfloor. Will be moulded using NPG resin so can be as complex as need be.
Preference is to lift as little of the deck as possible to insert them.

Phew. Is that enough?

JW.