1998 islander fuel tanks

[Bilpep]

Anyone know the dize and placements of the gas tanks on 98 islander? If ordered with one tank would the hoses be present and capped off in the empty tank compartment

 

[Hookup1]

134 (main forward) + 71 (aux aft) = 305 gallons. Not sure if hoses are installed on single tank purchase. Ask GW customer service. Pop the middle deck port and get a camera in there. Should be empty void. Look at the starboard side mid-compartment..

 

[Bilpep]

134 (main forward) + 71 (aux aft) = 305 gallons. Not sure if hoses are installed on single tank purchase. Ask GW customer service. Pop the middle deck port and get a camera in there. Should be empty void. Look at the starboard side mid-compartment..

Thank you! Thats what I thought but the diagram in the owners manual have the tanks reversed.

 

[Stephnic]

They are reversed on the Grady white site for my 1998 Islander.

 

[Hookup1]

They are reversed on the Grady white site for my 1998 Islander.

I checked the 1997 GW Islander Owners manual and it shows main tank aft but that is absolutely not the case on my 1997. I have had my deck up and read the labels off the tanks. The diagram that shows the tanks is a wiring diagram though is wrong in my case.

On my boat the forward fuel fill is to the main tank and the aft fill is to the aux tank. How are your fuel fills arranged? Pop the deck port and you may be able to read the label off the tanks.

 

[Bilpep]

I checked the 1997 GW Islander Owners manual and it shows main tank aft but that is absolutely not the case on my 1997. I have had my deck up and read the labels off the tanks. The diagram that shows the tanks is a wiring diagram though is wrong in my case.

On my boat the forward fuel fill is to the main tank and the aft fill is to the aux tank. How are your fuel fills arranged? Pop the deck port and you may be able to read the label off the tanks.

Thanks for the clarification.
Its a new boat for me and it only has one tank aft. After running out of gas due to a faulty gas guage i thought i only had a 71 gallon tank according to the owners manual. But its 134 gallons. I plan on adding the aux tank. All the plumbing is there. Do you know if all two tank configurations have two gas fills?

 

[Hookup1]

I can't believe that GW had a separate build for a single tank order. The 134 gallon tank appears to have been installed forward before the topside half of the boat was installed. Does anyone know if the tank can be removed thru the helm deck hatch? The aux tank is easy enough to add as an option except for the fuel fill and vent hoses. How many fuel fills on the starboard side on your boat? Mine has two. Also there are valves in the aft port storage compartment for main/aux switchover. Seems like this could be a big project.

The 134 gallon tank won't fit in the aft fuel compartment. The cockpit deck hatch (from the steps up to helm) has two deck ports. The forward one gives you access to the 134 gallon forward tank which extends forward under the helm platform. You can change the sending unit thru this opening. I used a WEMA 16" sending unit with a 2-prong automotive connector to keep everything factory. Use a rubber (not cork) gasket. I would also use a Permatex fuel safe gasket treatment on both sides. The salt water gets around the sending units and pits the aluminum tank underneath the sending unit. You need the gasket treatment to prevent it from leaking fuel.

The deck port aft of that one should be the void between a bulkhead forward (divides the fuel compartment forward/aft) and the bulkhead aft (closes off fuel compartment to the deck). The 71 gallon tank fills this area. I would be surprised if GW moved the bulkhead that divides the fuel compartment in order to place the fuel tank aft.

Here is a picture of EFX removing the aft aux tank. That tank you see in the middle is the aux tank.

 

[Bilpep]

I can't believe that GW had a separate build for a single tank order. The 134 gallon tank appears to have been installed forward before the topside half of the boat was installed. Does anyone know if the tank can be removed thru the helm deck hatch? The aux tank is easy enough to add as an option except for the fuel fill and vent hoses. How many fuel fills on the starboard side on your boat? Mine has two. Also there are valves in the aft port storage compartment for main/aux switchover. Seems like this could be a big project.

The 134 gallon tank won't fit in the aft fuel compartment. The cockpit deck hatch (from the steps up to helm) has two deck ports. The forward one gives you access to the 134 gallon forward tank which extends forward under the helm platform. You can change the sending unit thru this opening. I used a WEMA 16" sending unit with a 2-prong automotive connector to keep everything factory. Use a rubber (not cork) gasket. I would also use a Permatex fuel safe gasket treatment on both sides. The salt water gets around the sending units and pits the aluminum tank underneath the sending unit. You need the gasket treatment to prevent it from leaking fuel.

The deck port aft of that one should be the void between a bulkhead forward (divides the fuel compartment forward/aft) and the bulkhead aft (closes off fuel compartment to the deck). The 71 gallon tank fills this area. I would be surprised if GW moved the bulkhead that divides the fuel compartment in order to place the fuel tank aft.

Here is a picture of EFX removing the aft aux tank. That tank you see in the middle is the aux tank.
View attachment 17516

The hoses are in that compartment and are capped off. I only have one gas fill.
Thanks again for all of your advice. Happy and safe boating!

 

[Hookup1]

So there should be hoses coming up in the fill area that are capped off as well.

Are there any fuel valves in the back of the boat?

 

[Bilpep]

So there should be hoses coming up in the fill area that are capped off as well.

Are there any fuel valves in the back of the boat?

No valves. I guess it was ordered with one tank. Hoses are there but capped off. Adding the aux tank will be my winter project to get more range per fill up. Hopefully the extra weight wont slow me down too much.
How is you powered? What do you cruise at and WOT

 

[Hookup1]

I'm running Yamaha F150's with 17 x 14 1/4 3-blade Yamaha Reliance stainless. I do most of my running around at 24 knots. On a flat day or in the bay I can run 28 knots. I don't remember what it runs at WOT.

I'm trying improve lift and lower planing speed. I spoke to Ken at propgods.com and he recommended swap for 15 x 14 4-blade. Thinks my low speed performance would significantly improve and maybe even my top end speed.

I installed new props this Winter in prep for my Florida trip in February. Have not run them yet.

https://propgods.com/shop/ols/products/ptz4 (bought these)
or these
https://propgods.com/shop/ols/products/ptz3 (similar to Yamaha Reliance)

 

[Bilpep]

I'm running Yamaha F150's with 17 x 14 1/4 3-blade Yamaha Reliance stainless. I do most of my running around at 24 knots. On a flat day or in the bay I can run 28 knots. I don't remember what it runs at WOT.

I'm trying improve lift and lower planing speed. I spoke to Ken at propgods.com and he recommended swap for 15 x 14 4-blade. Thinks my low speed performance would significantly improve and maybe even my top end speed.

I installed new props this Winter in prep for my Florida trip in February. Have not run them yet.

https://propgods.com/shop/ols/products/ptz4 (bought these)
or these
https://propgods.com/shop/ols/products/ptz3 (similar to Yamaha Reliance)

I should be fine with the extra weight. I have 200 HO etecs.
I cruise at 34 mph. The extra range will be worth it to me.
Happy and safe boating in Florida.

 

[Stephnic]

My 1998 268 was ordered with just the main tank 134 gallon tank. The tank is also located in the forward compartment. When I pulled my hatch up the fill hose and vent hose are already run and capped off and the wires for the fuel gauge are also there. I also want to add the Aux tank for the additional range. I just repowered with F150’s. I am averaging about 1.5 mpg.