Which cap is the aux

RussGW270

GreatGrady Captain
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Since I do not trust it is backwards, which fuel cap is for the main and which is for the aux tank? I want to make sure to treat the aux one for my maintenance.

2004 Islander 270.

Thanks

R
 
In general, the fills are in the same order as the tanks. So which tank is which? The specs for that model year will tell you the tank capacities and assuming that the aux tank is smaller, one way that may help is to pop off the deck plates that allow access to the plumbing and fuel level sender. Most tanks will have a label attached near there that list the tank capacity and other info like manufacture date. The top of the tank in that area may need to be cleaned to see a label..
That said, I am pretty sure someone on this forum will know for sure
 
Cool, that was what I was figuring, but you never know with this boat. I am treating the gas and always like to know which is which. The labels are junk atm. Will replace those soon too.

R
 
Actually, it looks like whatever tank is forward, uses the forward cap. On the 2004 Islander, the AUX tank is forward so the forward cap would be the AUX tank.

I will wait to see if someone confirms this.

Thanks!

R