outboard fuel flow meter

Haven't-a-Clue

Haven't-a-Clue

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Hi, I'm Very new to all this, so if I do it wrong, sorry! We're just 4 weeks from entering the wonderful world of motorboating and it's cost us just about everything we have (but no regrets)! In order to keep our running costs as low as possible, I think we need to fit a fuel flow meter to our Suzuki 115hp outboard, but we're cash poor (I really mean POOR). Does anyone out there know of a budget method of accurately measuring outboard fuel flow in lts per hour? I am a fairly competent mechanic and am quite prepared to do most jobs on motors. I'd appreciate any suggestions, funny, rude or useful! I must just add, I'm dead impressed with the helpfulness of people on this site and have picked up some good tips already. Keep it up and many thanks.
 
I'd be a bit worried that you might spend so much time worrying about the meter reading, you forget to enjoy the boating!
My suggestion would be to try to get some good guides about an optimal cruising speed, and hang around that level,except for odd times. More weight onboard,wind,tide, head on seas will all change the fuel consumption,-meaning there isnt much you can do about those factors.
Maybe think in terms of a tank of fuel costs so much and gives me 2/3/4 whatever hours of fun. You should be able to get a chart from somewhere of rev/lph as a good guide. At least you can then visually see where the pain cuts in(!). I know that 2500/3500 revs is a reasonable speed/cost balance for my petrol inboard. If I do 5000 revs for a bit of fun, at least I m aware its a nasty bill, even if i dont know exactly a numerical amount. (in which case, I d probably be crying, instead of laughing!)
 
On my old outboard boat we had no built-in tank but 4x 25L outboard tanks and a 12L reserve, the need to change tanks meant you knew very closely how much you had used and when to head for fuel. After a bit of use consumption averaged 3mpg and that was sufficient for planning purposes...
 
Any fuel meter will cost money. If you are using portable fuel tanks just keep an eye on how long they last at what crusing speed. When cruising I would hope that fuel consumption is at least half the maximum that Suzuki quote. Previous comment about load, conditions etc DO make a big difference.
 
Wow, 3 replies already! Don't worry I'm going to use and enjoy the boat no matter what it costs, but in the line of work I'm in (anaesthetics 23 years now) I like to know the numbers (sad, innit). Re the pain, no pain, no gain I guess! I'll keep looking though! TA
 
On our Ribcraft 585 we had a Suzuki DF115 outboard which used to return just under 1litre per mile at 25 knots if that's any help.

Mind you that was on the plane - don't know what type of boat your o/b is on.
 
Am also interested in any replies you get. It does look a very good engine.
All i know is they do, do a Multi-Function Tachometer for it, what it covers i'm not sure, it might be worth phoning the UK distributer for Suzuki and asking them, they should also be able to give you a price for the unit.

You haven't bought a Merry Fisher by chance?

Cheers and welcome to the madhouse/ i mean forum. /forums/images/graemlins/grin.gif

Al.
 
Thanks for the welcome Al (and indeed everyone who replied) yes, I DID buy a Merry Fisher, how did you know!? The multi-function tach doesn't include fuel flow, or at least it didn't when we went for our test drive (oops, sorry sea trial!) In fact, I don't remember even seeing a fuel gauge so I guess I'll be taking care (and lifting up the access panel thingy regularly!)
 
We happen to look at a Merry Fisher 625 Legende at the weekend, and it had that engine, so i quessed thats what you had bought.
Where did you sea trial it??

I am 99% sure it did have a fuel gauge on the dash.

Have you phoned Suzuki to ask about a flow meter?

I presume its the 625 you've bought.
I liked the boat, and the Legende edition certainly makes it look very smart with the blue hull and interior. For us we felt the down side was no real seat for wife and son to sit whilst on the move.
Good solid boat with good sea hull, i'm concidering it, but SWMBO still needs convicing.

I'd like to hear your take on it, and the engine performance.

Have a great time with her.

Cheers

Al.
 
Yep, get the Navman that jon and major suggest imho. Navamn is well-respected gear and there's nothing cheaper that's any decent quality.

But do connect it to your GPS so you get mpg read out, not galls/hour. The connection uses a protocal called NMEA. It's dead simple, a two wire thing that transmits data in 5 volt pulses at 9600 baud. Nice easy dinosaur age technology and dead reliable. Your GPS unit will transmit the boat's speed to the Navman, which knows the fuel flow rate, and the navman will then compute mpg, easy peasy.

The benefit of mpg read out is that you will then know (assuming you know how many gallons of fuel you have left in the tank...) how many miles you can go before you run out, not how many hours. And if you want to experiment and find the boat's sweet spot in terms of speed but decent fuel burn, you need that in mpg not gph.

Ok you can convert gph to mpg but you need a blimmin calculator and it's a faff. Much better to get mpg read out right there on the dashboard

Nice boat, have fun!
 
Yerp, yer right agin, it was the 625 from the nice chaps at southern m'boats, so as you've probably gathered by now, we burbled down the 'Amble to the water and wow! yippee, dunnit go mista! Re wife and kid(s), wife yes, kids none. Where d'ya the money came from? We didn't think the blue paint job was worth the extra, so stuck with white, but we are getting the awning thingy and I CAN'T WAIT much longer to get my mitts on it! As I said earlier, no matter what it costs, we're GONNA enjoy it. We'll be mooring at Deacons from 1st April and 'cos of the job I do, don't meet people I could call friends, so we'll be looking to make some new ones in the world of boating. Cheers to all from Nobby-no-friends!
 
Well done.

I have the sister ship, the Beneteau Antares 650, which is basically the same hull.

I stuck with the Suzuki 90, which gives me 25 knots and can do 27 downhill, which is literally possible in the Swellies, between N Wales and Anglesey.

They are great sea boats and can take a big head sea with no trouble.

Be careful in a following sea and make sure you do not overtake a following wave. Practice it and learn good throttle control. It is the only time I found it to be 'frisky'.

Depending where you go, I have a auxillary engine - Suzuki 6 hp, mounted next to the main engine, which means that I always have 'get you home' power.

Finally, before every trip think who else in the boat knows what to do if you go overboard.

By the way, there is a fuel gauge on the dashboard. Or, at least, there should be.

I think we deserve a report of your first trip, along with pictures.
 
Here is a pic of the helm, i'm pretty sure the gauge on the right was a fuel gauge.
Sorry its not a great pic.
P1010283.jpg


Cheers

Al.
 
My boat has three gauges, Fuel on the right, the Tach/engine management in the middle (Same as yours) and the trim gauge on the left, which shows the angle of the engine in the water.

The gauge on the right in your picture looks suspiciously like the trim.

They are all standard Suzuki instruments.

I would ring your dealer and check, as you really do need a fuel gauge as you can't keep lifting the the hatch and looking in the cellar at the fuel tank. If I remember correctly, unless they have re-designed it, you can't lift the cockpit hatch on the 625 when the bench seat is deployed. That was one difference I liked about the Beneteau version.

If the fuel gauge was not an option, then it will be cheaper to have it fitted now before delivery.
 
Thanx fer the piccies, but Major Catastrophe is right: it's the trim indicator: damn useful for a novice like I, 'cos I don't think I could get the wing mirror to show it! It's only(!) 4 weeks to go (sob) but we saw the write up in this month's MBM and they said it's only got one interior light over the loo (or whatever it's called). So we went to my wife's fav TV (QVC) channel and bought some Osram 'Do-it' battery powered LED stick-on lights. HIGHLY recommended, Very bright £23 for four. Ho hum, and we 'aven't even got it yet! As soon as we do, there will be a report and piccies IF I can ever get a)this sodding computer to work and b) learn how to send piccies. I am, I'm afraid, not computer literate. Going back to the fuel gauge, SB's people are very nice and helpfull but their prices for fitting things are, shall we say, a bit steep. Not to detact from their sterling qualities, but I reckon I can fit it for less ( mainly 'cos I don't have to pay myself). Speaking of the Beneteau, the test MBM did a coupla years back said that for all practical intents and purposes, it's virtually unsinkable. Bearing in mind that they're basically the same boat can this be true of (soon to be) mine?
 
No boat is unsinkable, except the Titanic, but the 625/650 is pretty much bomb proof. They are great value for money and leave many other boats standing. Not only that but you don't get wet if it rains whilst out and you don't have to run for cover.

As to the lights, the Antares has three lights, one over the loo, one on the ceiling of the wheelhoues and one outside over the patio doors.

The only modification I am making is to build a marine ply shelf over the forward part of the berth which will hinge at the back. You can put bedding, spare clothes and other stuff on it and then push it to the ceiling and lock it out of the way. This gets over the main problem with small boat, the constant need to move everything from one side to the other before you can open hatches, go to the loo etc.

Another thing I have done is had curtains made - out of ripstop nylon so it doesn't rot - for the side windows and the patio door, that means you can sleep on board and you and your visitors can use the loo in peace. I used Jonelle Slim Track to hang them and curtains have velcro patches on them to tie them back when boating.

I have also had dark opaque material made up to fit over the insides of the windscreens - attached with velcro. Beside privacy, they stop the sun cooking the insides.
 
Guess where we're putting our lights!! And yes, we'll be fitting curtains for exactly the same reasons as you state. I presume that it's OK to drill the holes for securing the curtain track without affecting the integrity (or resale value when we trade up, which I KNOW will be in a couple of years!) I'm very interested in the shelf idea, so any tips would be most welcome. Re the windscreen shades, buy a space blanket (also known as an emergency warming blanket like they give out to runners at the end of the marathon). Relective, but doesn't leave you groping in the dark. Ta everso. PS where would you store an extra 10(?) litres of fuel just in case?
 
Really useful info Major.

I think the fuel gauge is a must, and if we bought one, i'd def get one fitted.
Lights easy enough to sort out, what about bilge pumps, i know it has a manual, but does it have an automatic one, and if not, is it easily fitted?

Your shelf thing sounds very interesting, can't quite understand what you mean, if you do, do it, please take some pics and e-mail them to me, as we would be interested to see it.

Curtains is another thing we would have to get, we have our oun sewer at work so making them up is easy, what has puzzled me is how to fix the rails on, is the wheelhouse sides, only single thickness, so if i put a screw in to fix a rail will it go right through to the outside??

I hope you are planning on hanging around for a while, as should we order this boat, i have a lot of questions to ask you.

Good to have you back.

Cheers

Al.
 
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