hooking up 4stroke kicker to existing fuel tank (starcraft islander)

[acarleson]

hello,
I'm adding a kicker to my starcraft with a built in fuel tank and an I/O. My kicker is a 4 stroke with a pull start/tiller operated, so all it really needs is gas.

I've read a bunch about how to hook up fuel to a kicker, but I just want to clarify a few things.

1) I read that you basically just add a T connector and run a branch off your main fuel line. Does this go before or after your fuel filter and water separator? Mine has an inline fuel filter, and then a standalone water separator, so the T could go before, in between, or after all of these. I'd like to avoid reducing the fuel pressure or anything as much as possible.

2) Just to clarify, I'll definitely need some line with a primer bulb. But is that all? My tank is under the deck, so I just want to make sure that a primer bulb is the only thing I need to work against gravity. So even if my tank is a few feet below my outboard, I can pump the bulb and the outboard will have fuel delivered, right? I don't need an electronic fuel pump or anything?

Thank you all

 

[matt167]

After water separator. And filter. It should do it. However if you're tank gets contaminated. Your not getting home. With a portable and fresh gas, you will

 

[acarleson]

@matt167 thank you!

I actually misremembered my setup. From the gas tank, in order, I have a water separator, and then an inline fuel filter, and then a pressure regulator. Photo attached.

I bought a brass T-fitting, where in this line should the T fitting go to branch off to my outboard?
Thank you!

 

[Scott Danforth]

it should be on a separate pickup and here is why

if you do not have check valves, the engine can start to pull air from the kicker motor or the kicker can start to pull air from the main motor and neither engine runs

if you add check valves, you add additional restriction in the lines and it works until a bit of dirt prevents one of the check valves from closing.

best solution, use a separate fuel pickup (many tanks have them), or a portable tank.

 

[acarleson]

@Scott Danforth hm does a separated pickup mean I’d have to pull up floor to get to my tank? I’m not even sure my tank has a separate pickup, is there any solution that I can use with an existing line? What about those fuel/water separators that have dual outlets, would that solve the air problem?

 

[matt167]

Use a 3 gallon portable under the rear seats. Way back when I was a kid, my dad ran his Honda 5hp off a Tee on the main line. It worked without issue.. but it gets contaminated and your not getting home

 

[acarleson]

How often does fuel contamination happen? If it’s fairly common, maybe a small external tank is the way to go. But if it’s more like a “worst case scenario” thing, I’d rather tie into my main fuel tank (if there’s a good way to do safely, like using a dual outlet fuel water seperator) and just keep a small tank as a backup. That’s way, most of the time, all I need to do to use the kicker is to switch a valve or whatever. But I still have a backup tank in case something goes really wrong. Thoughts? Thank you!

 

[Scott Danforth]

@Scott Danforth hm does a separated pickup mean I’d have to pull up floor to get to my tank? I’m not even sure my tank has a separate pickup, is there any solution that I can use with an existing line? What about those fuel/water separators that have dual outlets, would that solve the air problem?

there should be an access cover over the tank to check the sender and connections.

 

[acarleson]

@Scott Danforth

My islander does not have an access port. It's possible that it used to have one that was closed up by a previous owner, or it's also possible that mine just never had one (it's a 1968, I bet things were different back then). Given this, what would you recommend? I really doubt that my tank has a separate pickup and it doesn't seem to have an access port that I'm aware of, despite many many hours poking around every corner of that boat Thank you!

 

[matt167]

'68 islander, I'm pretty sure would have originally had tanks above the deck, underneath the 2 front seats. If you have below deck fuel tank, it's probably a previous owner modification done when the boat was refitted

 

[acarleson]

@matt167 yes, I have a below-deck tank. Just storage under the seats, and no access hatch... bummer

 

[acarleson]

I think for me the biggest question is still about how often things go wrong when you have an outboard hooked into the main fuel tank. If the worry is fuel contamination, but that only happens rarely, or if the other worry is sucking air in, but that risk can be eliminated/mitigated but using one of those dual-outlet fuel/water separators... I have no problem just tying into my main tank but keeping a small aux tank on board just in case.

If possible, I'd like to avoid using a portable tank for my main outboard tank. With my boat setup (no rear seats, etc) it would be significantly easier to be able to just run my kicker off of my main gas tank, unless there's a medium-to-high chance of something going wrong.

Thank you!

 

[Redrig]

I had this same question and situation come up in my boat.

I tried one of those dual outlet fuel / water separators and my kicker kept sucking in air . IDK why that was happening since I have check valves for both engines, but it was. Even with a priming bulb , it would just pull air . So I gave up on that approach.

I ended up just putting in a valve like this , so I can manually switch it when I am running my kicker. ( I dont run it that often ) but the drawback here is you need access to it , and cant forget to switch it back to the main engine.

The ideal situation Like Scott mentioned I think is have the dual pickups in the tank , so there is no shared connection.

 

[acarleson]

interesting, thanks. Just curious, which water/fuel separator did you have? That seems.... not great.

Ok, so it sounds like I need to decide between a dual-outlet filter, a switch system, or dual pickups, and all have their drawbacks and horror stories (except for the dual pickup, which I don't have). I guess my last question is.... how tough is it to add another pickup? a DIY job or would a shop need to do it?

If I go with one of the other options, is it the case that it'll either suck in air, or it won't? Like I guess if I test it out and it works for a few hours without sucking in air, is it probably pretty reliable? And how will I know whether it's sucking in air or not?

Thank you!

 

[Redrig]

If you can get a fuel separator with dual outlets working , that's a great setup. Many folks here use that with success. Mine is just an aftermarket Moeller separator . The main engine always worked just fine, the kicker side is where I had the problems. The kicker is only 5hp and doesn't have much pull at all , so maybe that's why it didn't work idk . I just got tired of fighting with it , the kicker would constantly die and the primer bulb wouldn't pull any fuel. so I added the selector valve and no more "air in the line" issues.



adding another fuel pickup will depend on the tank type. I have an aluminum tank , so adding a new pickup will involve welding on a new bung , I plan to do that one day . but for now that selector valves works just fine.

Oddly enough , I have this exact issue on my motorhome as well. Main engine is fine , but the generator line runs dry , so I am adding a dual pickup there too.

 

[H20Rat]

Oddly enough , I have this exact issue on my motorhome as well. Main engine is fine , but the generator line runs dry , so I am adding a dual pickup there too.

Not having dual pickups is highly unusual on a motorhome! They are almost always set up so the pickup for the genny is higher than the main engine. Done that way so it is impossible for a generator to empty your tank and leave you sitting.

 

[acarleson]

Thanks for all the responses. I already ordered a dual-outlet separator so I'll at least give that a try. But, quick question (similar to the question as above).... where does it go in the fuel system? I have a garbage separator now and then an inline filter and then a pressure regulator. I'm guessing that the dual-outlet separators replace the inline filters as they have a filter built in, but should that go before or after the pressure regulator?

I guess my thought process is that my regulator is only a single outlet, so either the separator goes before the pressure regulator and the outlet that goes to the main motor will have the regulator? Or maybe I need another pressure regulator for the kicker, although I'm not sure if kickers need a regulator?
Thanks

 

[Bondo]

Ayuh,..... You shouldn't need a regulator, at All,.......

I'd run it, from the tank, to the valve Redrig posted, to the canister filter, out one port to the existin' fuel pump, 'n out the other port, to the outboard,.....

Get ridda the in-line filter, 'n the regulator,....