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1986 OUTRAGE 20 Replacement Fuel Tank
Posted: Mon Dec 30, 2019 11:46 am
by ekalb
I need to replace the fuel tank on my 1986 Outrage 20. I got a quote from Florida Marine Tank a while back that listed their proposed replacement tank as a 77-gallon. I have old literature saying the fuel tank is a 77-gallon tank as well.
I'd like to order a tank from Luthers in Rhode Island, but they only have the OUTRAGE 22 dimensions on file.
Is the 77-gallon fuel tank in an OUTRAGE 20 identical to the 77-gallon fuel tank in the OUTRAGE 22 of the same era?
I would be very surprised if Whaler used two different 77-gallon tanks. I know the OUTRAGE 22 has a live well space that the fuel tank cavity in my OUTRAGE 20 does not have. I have to assume the cavity and tank dimensions are the same, but I would love some real world confirmation before I give my deposit.
Re: 1986 OUTRAGE 20 Replacement Fuel Tank
Posted: Mon Dec 30, 2019 11:55 am
by ekalb
Here are the dimensions [Luther's] are using which match some searches I have done about a 20' tank:

- Fig. 1. Tank Dimensions from Luther's for 77-gallon Boston Whaler OUTRAGE 22 tank.
- tankDimensionsA.png (80.68 KiB) Viewed 9075 times
Larger image at
https://postimg.cc/PPKgYb68
Re: 1986 OUTRAGE 20 Replacement Fuel Tank
Posted: Mon Dec 30, 2019 12:00 pm
by jimh
ekalb wrote:Is the 77-gallon fuel tank in an OUTRAGE 20 identical to the 77-gallon fuel tank in the OUTRAGE 22 of the same era?
As far as I know the hull of the OUTRAGE 22 and OUTRAGE 20 are very similar--identical really except for the aft two feet. From what I can see, the only difference in the hulls occurs aft of the fuel tank cavity. I would expect the 77-gallon fuel tank dimensions are the same.
But I understand your reluctance to commit to an expensive custom-order tank without some additional confirmation. I recommend you contact Boston Whaler customer service and ask them for a confirmation.
Re: 1986 OUTRAGE 20 Replacement Fuel Tank
Posted: Mon Jan 06, 2020 10:16 am
by BDBinWV
I recently purchased and installed a 77-gallon tank from FMT. The dimensions shown on your original post are slightly different from the dimensions of the tank I removed from my 1989 Revenge 22. Your drawings reference a constant side height of 10.75-inches. My original tank and the replacement tank both had a varying height from 9.875 to 10.75-inches. The 9.875-inch dimension was at the aft end and the 10.75-inch dimension at the forward end. I don't think there would be enough clearance for an additional 7/8-inch of height at the aft end.
Though I could be wrong.
Re: 1986 OUTRAGE 20 Replacement Fuel Tank
Posted: Mon Jan 06, 2020 10:39 am
by jimh
Is there a drawing from FMT that an be reproduced in this discussion that shows their dimensions for a 77-gallon tank for a Boston Whaler?
Re: 1986 OUTRAGE 20 Replacement Fuel Tank
Posted: Mon Jan 06, 2020 11:57 am
by BDBinWV
Re: 1986 OUTRAGE 20 Replacement Fuel Tank
Posted: Tue Jan 07, 2020 11:58 am
by ekalb
FMT CC'd Bostom Whaler in on my email to them questioning if both 77gallon tanks were the same and the response I got was this:
"Unfortunately due to the age of the boat, we no longer have the part numbers in our system. However, I would be pretty confident that the fuel tanks would not be the same as the interior geometry of the hulls would have been different."
My gut disagrees with this.
Re: 1986 OUTRAGE 20 Replacement Fuel Tank
Posted: Tue Jan 07, 2020 12:17 pm
by Phil T
Re: 1986 OUTRAGE 20 Replacement Fuel Tank
Posted: Tue Jan 07, 2020 12:27 pm
by ekalb
I did find that when I was first looking for confirmation. Thanks Phil
I was a bit concerned that I think there are other important dimensions that are being left out of that post.
I have been going back and forth with FMT today and they only have one 77-gallon tank in their system. They don’t differentiate between the OUTRAGE 20 and OUTRAGE 22.
Re: 1986 OUTRAGE 20 Replacement Fuel Tank
Posted: Tue Jan 07, 2020 12:51 pm
by Phil T
Why don't you pull the existing tank to really get to the bottom of it.
Re: 1986 OUTRAGE 20 Replacement Fuel Tank
Posted: Tue Jan 07, 2020 2:19 pm
by ekalb
Phil T wrote:Why don't you pull the existing tank to really get to the bottom of it.
I will be doing just that.
I was just hoping I could iron out these dimensions before hand. It would be much easier for me to de-rig everything, get the tank out, reinstall the new, and rig everything back up while its fresh in my mind. Even while labeling stuff, I work better when in short time windows.
I was hoping to avoid pulling it and then have to wait several weeks to get the tank in. I guess thats better than ordering the wrong tank though.
Re: 1986 OUTRAGE 20 Replacement Fuel Tank
Posted: Tue Jan 07, 2020 3:57 pm
by jimh
ekalb wrote:...would be much easier for me to de-rig everything, get the tank out, reinstall the new, and rig everything back up while its fresh in my mind
I assume you must be referencing all the rigging related to the center console, which probably will have to be moved out of the way to get the tank cavity deck section out of the way. Look at this as an opportunity: you might want to plan on some electrical power distribution updating while you have the center console out. The typical c.1986 Boston Whaler electrical power distribution wiring was rather minimalist, and it is now 34-years-old.
When working on complicated wiring and rigging, I recommend you take many digital camera pictures of the installation before tearing it down. I do this now with my smartPhone camera. Having some detailed images can be a big help. A careful sketch of the circuitry is also very useful to have.
There is not much wiring related to the fuel tank itself: the ground conductors and the tank level sender (if used). The hose connections are simple, too: in, out, vent. They may also need updating, and particularly if the rubber hoses are not clearly marked to be tolerant of alcohol fuels.
Re: 1986 OUTRAGE 20 Replacement Fuel Tank
Posted: Tue Jan 07, 2020 4:49 pm
by ekalb
Thanks Jim.
yeah, I was referring to the center console. You're absolutely right though, It makes way more sense to start from scratch with most of the wiring at this point. I will also need to recore the deck.
I appreciate all the advice and I will update this thread with exact measurements for a 20' outrage tank, so that people can reference it in the future.
Re: 1986 OUTRAGE 20 Replacement Fuel Tank
Posted: Tue Jan 07, 2020 9:43 pm
by dtmackey
Where are you located? Just had Luthers build a tank for an 18' Outrage and his work is top notch and he's located in the Northeast if your close to there. I thought his pricing was very competitive.


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