Completion of 1979 Revenge 22 Fuel Tank Refurbishment

Repair or modification of Boston Whaler boats, their engines, trailers, and gear
steelhead55
Posts: 36
Joined: Mon Jan 11, 2016 12:46 pm

Completion of 1979 Revenge 22 Fuel Tank Refurbishment

Postby steelhead55 » Tue Jun 12, 2018 1:49 pm

I completed the fuel tank removal, refurbishment, and replacement project [for a 1979 Boston Whaler REVEGE 22] with what I consider to be great success. The problem with these versions of the Revenge is the ridiculously large deck extends past the control console into the cabin. As shown in images linked in my previous posts at

http://continuouswave.com/forum/viewtopic.php?f=6&t=3202&p=18261#p18261

I removed the consoles and cut the deck at approximately the same place that the more modern (c.1982 and forward I believe) decks are cut.

I emptied the tank and replaced the fill, vent, and pickup with new 6-inch aluminum plates by Seabuilt;

http://www.seabuilt.com/plates.php

These are very robust, and are an excellent choice for existing polyethylene tank refurbishing. You can see the plates [in the webpage linked above]. You can also see at the bottom of the tank I added a 1-inch piece of PVC pipe that runs the length of the tank to facilitate water movement from the forward end of the tank cavity to the stern, which will be foamed into place. I also added a fuel sending unit which can be seen just below the fuel fill line.

Image

These are gasketed on both sides, and form a nice tight fit with Nitrile rubber gaskets.

Before I foamed the tank into place, it took the opportunity of having the tank out to correct what I consider a couple of existing design flaws. The first is that the cavity near the Port side, near where the fuel fill lines enter the boat, has no mechanism for water to be relieved. To fix this I added a 1' inside diameter fiberglass tube between the fuel tank cavity and the port cavity so that water can flow into the fuel cavity. See pic below. You can also see the front part of the deck installed here.

Image

Generally I want to keep water out of the fuel cavity. Previously, water in the fuel cavity deformed the Polyethylene tank, denting it and reducing its capacity from 70 gallons to 55 gallons. To prevent water from entering the fuel cavity bottom and remaining there in perpetuity, I added a 1-inch diameter fiberglass drain tube from the fuel cavity to the fish well. This tube will be plugged when using the boat, but I plan on removing the plug when not in use to facilitate water movement from the fuel tank cavity to the fish locker for complete draining. You can see the fiberglass tube epoxied in place here.

Image
and here

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I used X30 expanding foam from Tap Plastics to foam the tank in place. I left the bow and stern section of the tank open, so that water has a place to collect, and move from bow to stern of the tank. Before closing the tank into place, foam was wedged in the bow and stern sections to assist in resisting movement of the tank in the cavity.

Image

After filling with gasoline for the first time, with the deck off to insure nothing was leaking, the boat is now ready to be put back into use.

jimh
Posts: 11673
Joined: Fri Oct 09, 2015 12:25 pm
Location: Michigan, Lower Peninsula
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Re: Completion of 1979 Revenge 22 Fuel Tank Refurbishment

Postby jimh » Wed Jun 13, 2018 8:33 am

Thanks for the interesting narrative and images of your project. I do note that on the manufacturer's website for the access plates you used, there is a caution:

Not for use on gasoline tanks


Am I misreading the manufacturer's website?

Also, the 6-inch access plates are $175 each. That's a cost of $525 just for the new access plates. This was not an inexpensive project.

Re the Port side rigging tunnel that seems to go nowhere at the stern: my 1990 REVENGE 22 has this same sort of rigging tunnel on the Port side. The tunnel dead-ends at the aft end. By c.1990 Boston Whaler figured out they should install a drain tube at the end of the tunnel. A relatively small diameter somewhat rigid tube, perhaps 3/8-inch ID, runs to the Starboard side tunnel from the Port side tunnel. The tube is sloped downward to Starboard from Port, so its position on the Port tunnel is a bit higher than optimum to drain the last drop of water out of the Port tunnel. I don't have a good concept of what the purpose of the Port tunnel was supposed to be. On the larger 25-foot hull there are similar dual tunnels, Port and Starboard, but there are also dual sumps, Port and Starboard, and the Port tunnel drains into the Port sump, as I recall.

ASIDE: I made most of the images into in-line images to give readers a better chance to see your work.

steelhead55
Posts: 36
Joined: Mon Jan 11, 2016 12:46 pm

Re: Completion of 1979 Revenge 22 Fuel Tank Refurbishment

Postby steelhead55 » Thu Jun 14, 2018 12:24 pm

Hi Jim

Yes you are correct about the language from their web site about not using on Gasoline tanks. In talking with the welder who added the fuel fill to one of these plates for me, he stated that the company has that on their website (product is patented) to prevent someone from drilling into there tank and blowing themselves up during installation, or inspection. The company that did the welding uses this product on all of the aluminum tanks that they manufacture. (Company is in San Diego, and manufactures lots of custom aluminum tanks)

It is pricey, but I actually hunted around online and found them for a little more $120 each. I feel like it was good value because I have the utmost confidence in polyethylene tanks not to leak / corrode, and consider them to be a superior product to aluminum.