Use external fuel tank instead of inbult petrol tank

Morris_fe1s

I would like to go from using the inboard fuel tank to an external 22 liter tank on a mercury 115 2006 engine. (outboard engine)

Does anyone know where the pipe from the fuel tank connects to the engine please?

I am not so clear on the manual tbh

Thanks

fergal.b

It might be raped up with the wiring harness and then goes into the fuel pump that looks like this. You might be better off connecting it before your water separator coming from the tank, remember if the external tank is going to be put in a compartment it may need to be vented to the outside of the hull to stop the buildup of vapours .

Morris_fe1s

please see 1-2 attached.

where is the fuel intake?

Morris_fe1s

another 2 photos please see

i do know what it a normal set up should look like but theres something small missing here

fergal.b

I'm not up to speed on these new engines but this looks like the fuel line into the fuel pump.

Morris_fe1s

p.143 must be a-b? i guess that links up to that pipe you highlighted fergal which is also the one i thought too..
http://www.mercury-marine.eu/cache/Documents/Mercury/OptiMax%2090/0/en-GB/DocumentFull.pdf

fergal.b

If you peel back the cover on your harness you should see a connection for the fuel line it should also have fuel stamped onto the pipe.





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Morris_fe1s

i assume you do not mean picture marked a on p137 of
http://www.mercury-marine.eu/cache/Documents/Mercury/OptiMax%2090/0/en-GB/DocumentFull.pdf

u mean the grey casing tube which protects all the tubes at the front of the outboard facing in towards the boat?

fergal.b

[QUOTE=

u mean the grey casing tube which protects all the tubes at the front of the outboard facing in towards the boat?[/QUOTE]

Yep




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Morris_fe1s

it would appear not...

Morris_fe1s

fergal.b wrote: »

I'm not up to speed on these new engines but this looks like the fuel line into the fuel pump.

Also fergal is there a reason u think its the tube marked with your white arrow opposed to the top two black pipes?

fergal.b

Morris_fe1s wrote: »

Also fergal is there a reason u think its the tube marked with your white arrow opposed to the top two black pipes?

The little box it's going into looks like the fuel pump and the part with the red cap looks like the fuel filter so your fuel would go through them before going to the injectors, again I'm not up to speed on this engine just guessing





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Morris_fe1s

I would have thought if photo 1 is where the fuel goes in - maybe photo 2 cable is in the wrong place

fergal.b

It could be a pulse hose from the crankcase.






1 -- Fuel supply from boat fuel system
2 -- Fuel lift pump
3 -- Pulse hoses from cylinder/crankcase (3 & 6)
4 -- Water Separator-Fuel Filter
5 -- Fuel supply to vapor separator
6 -- Vapor separator
7 -- Vent hose to throttle body
8 -- Electric fuel circulation pump
9 -- Fuel supply manifold
10 - Fuel injectors
11 - Fuel return manifold
12 - Pressure regulator
13 - Test fitting (low pressure)
14 - Test fitting (high pressure)

Morris_fe1s

Image 1: top pipe entering the box next to fuel filter
image 2: under the outboard hidden near where the other cable enter the engine

Can anyone tell me what the function of image 2 is please?

Morris_fe1s

your post at 12:01 fergal with the whitearrrow...if u look down from your arrow there is a white plastic nozzle nip that the pipe fits onto snug.. at 7 oclock the old fella reckons thats the fuel intake... has to be it??

fergal.b

Try it, put a bit of pipe on it and fill it with fuel and see will it start.

Just to get things straight, was this engine running on this boat with an internal tank and you just want to swap to a new tank or is this the first time the engine has been put on the boat and your connecting the fuel lines for the first time.



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breghall

My 2 cents is that as far as i know, the unit with the red cap is a "vapour separator" i.e. it catches any water in the fuel which can then be drained out. My guess is that the hose in the top RHS corner is the fuel intake...

fergal.b

It looks like fuel line 33 from the primer bulb is at the top






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Morris_fe1s

E-mail from Mercury USA

"The fuel inlet hose should be connected to the nipple at the bottom of the fuel pump..follow is a diagram for fuel and air flow.."

Morris_fe1s

Final email from mercury:

"Morris the fuel inlet hose coming from the fuel tank should go into the white plastic connection underneath the arrow.."

This is misleading as:
(1) 33 refers to the the fuel intake from primer bulb.
(2) Mercury state its the plastic nip at the bottom of the fuel pump which is not infact labelled.

breghall

breghall wrote: »

My 2 cents is that as far as i know, the unit with the red cap is a "vapour separator" i.e. it catches any water in the fuel which can then be drained out. My guess is that the hose in the top RHS corner is the fuel intake...

Well that hunch was a mile off......

guess it's the white nozzle at the bottom of the pump as Mercury say then..