Fuel line arrangement

Donnie144 · 22 March 2007, 22:29

I’m trying to clean up the transom of my boat and the fuel bulb and fuel flow meters are causing havoc on getting the wraps around the rigging. OK so now the question All of the layouts I’ve seen has the primer bulb in the first couple of feet from the motor. I want to relocate this to the fuel filter. Should the fuel flow meter be in front of or behind the primer bulb? I want to run 3” of hose from the filter to the primer 3 more inches of hose then the flow meter then 3-5 feet of hose to the motor. Does anyone see a problem with this? Can you use too large of a house to feed the motors? Assuming you get tight connections at all of the fittings. I know I have probably confused the hell out of everyone so I’ve attached a sketch,

jyasaki · 22 March 2007, 22:36

Realistically, I don't think it makes a difference. You do want your fuel sensor to be mounted at the bottom of a U bend, though, to keep air from being trapped in it which will give you false readings (or no readings, or something.)

But as far as order goes, fuel has to travel through everything eventually to get to the motor anyway...

My boat is plumbed such that the fuel comes from the tank under-deck to the transom, goes through the Racor, to the primer bulb, then out the back of the transom to the motor. (No fuel sensor, yet. It will probably be plumbed in after the bulb, since it's easier to get to.) Have yet to have had to prime it with the bulb, other than when I replaced the Racor mounting bracket.

jky

Donnie144 · 22 March 2007, 22:47

Hey Thanks JKY that was my thought also but wanted to make sure I wasn't missing something. Looks like it's off to the parts store to tweek something else. So has anyone ever got their boat to where they want it? It seems like as soon as i think i will have it where i want it something else comes to mind. But then again i will also go out there looking for something to do also

jyasaki · 23 March 2007, 17:29

Still have tank racks, a current line reel, deck lighting, a freshwater shower, and an anchor capstan to go. And this only emcompasses the current plans...

jky

Donnie144 · 23 March 2007, 18:58

I have tank racks builts one accross the stern and then one acrross the bow that also works as a bow pulpit and will provide a place to mount the capstain for anchor and crab pots. I never though of a fresh water shower...I have a raw water wash down to keep divers cool during the summer months. What are you calling a current line real? I may be interseted in one of those if it's what i think it is. Here are pics of the racks i've built. If you have AutoCAD and want a copy let me know i will send it too you. Looks like i will have take photo's of the back rack this weekend.

jyasaki · 23 March 2007, 20:49

Current line reel: Sort of like a garden hose reel. Will probably mount it on the sort-of swim platform I have, opposite the side with the dive ladder.

Probably 100 to 150 feet of polypropylene line, most likely 3/8", with something like pool floats every 25' for visibility. A Polyform buoy at the end so you can see where to swim to in order to intercept the line should you be carried past the boat.

My current setup has the line in a mesh bag in a storage area. Setting it up isn't too bad, but putting it away is a pain in the butt. Be a lot easier to just crank it up.

jky

MarkM · 28 March 2007, 10:59

I have mounted the flow meter between the fuel filter and the primer bulb. The flow sensor should be in a vertical position.
The water separator/filter and the fuel hose must have enough flow rate; I had a problem there.

Donnie144 · 29 March 2007, 00:44

JKY
i figured that is what you ment by a current line but i just haven't seen them much longer then 50'. I just use one of my moring lines whith a float attached to the end but that only gives me 30' a far cry from the 150' you are looking for.

Mark

thanks for that i wasn't sure what side of the primer bulb the sensor should be on. As for fuel flow i wanted to make sure i never had problems so i have a 5/8" line feeding the filter and a 60 GPH filter feeding motors that might make it too 20 GPH combined if over reved. YOU gotta love these new 2-strokes.

matt h · 29 March 2007, 07:32

hi there, i see your running the TLDI, how s the engine, good points and bad, fuel economy??
sorry to change the thread!! but too good to miss!!

Donnie144 · 29 March 2007, 16:32

I can’t say enough good stuff about them they are great motors. At the dock they are quieter then anything else I’ve been next too. They just seem to sip the fuel. I’m going to give you fuel consumption number for a pair of 90’s. So if you are only running on cut them in about half.

Fully loaded with divers and gear approx 2,000 pounds and a 12x21” prop she is slow out of the hole but still work.

WOT approx 5100 RPM’s 35-38 MPH 18 gph
Cruise 3500 RPMs 24-28 MPH 8-10 gph

Running with full fuel and 4 up
WOT approx 5500 RPMS 55-58 MPH 18 gph
Cruise 3000 rpms 35 mph 8 gph

2 divers 1 captain and gear approx 1000 pounds and a 12 ¾”x17” prop

RPMs max out at 5800 RPMs @ 35 MPH burning 19.3 GPH

Numbers are taken from a Lowrance GPS with fuel flow sensors to each motor.

Bad points you need to find a tech that is cleared by Tohatsu or Nissan specifically for the TLDI to keep warranty. Just because they sell them doesn’t mean they have a tech that can work on them. The only other bad thing about them that I can think of is that the tachs are not very moisture resistant. I find they will fog up and will occasionally give really odd readings. The RPM pin will set there and bounce between 0 and 6000 RPMS and kind of fun to watch but that isnt’ what I want my tach to be doing. So all and all really minor stuff.