Fuel Tank Replacement 1975 F30 Clean Machine

[Surf and Sand]

I have finally had time to start working on the boat. One of the first things was to replace the cockpit deck, as it was a mess. When I removed it, I found more work to be done (no way !, you say). Anyway, I found the fuel tank (gas) had been replaced in the past with fiberglass, and it was leaking a tiny amount.

I am going to replace it with aluminum and was looking for others who have done this and might provide some advice before I get going. I have read the article by David Pascoe.

Do I coat the tank and foam, or not coat the tank, is just one of the things that come to mind.

Thanks in advance !

[prowlersfish]

Never coat the tank with foam , some boats foam the tank in place , but that causes issues .( holds in moisture and corrodes the tank ) On my F30 clean Machine the tanks where replaced with a single tank of a 150-175 gal cap. square tank . The tank was custom made .

[Surf and Sand]

I got the deck out this weekend. I found a fiberglass tank, approx 311 gallons ! I knew it had been replaced in the past, but I wasn't expecting something so big.

2 questions come to mind: How do I go about getting this thing out ? Or should I contract someone to do this ? Also, when I replace it, is there any value to installing 2 tanks rather than 1 ? I am considering installing 1 tank of about 150 gallons.

Thanks !

[turtlem1969]

I have always been a firm believer in the two tanks over one big tank, run one down to a quarter on your way out and you always have enough to get back on the other. If ya got twin engines always run two tanks that way if there is fuel problems with one you can get back with the other. just my $0.02

[k9th]

I replaced both of my galvanized steel tanks this past spring with aluminum tanks because I detected cracks around the base of the fill tube on both tanks. I did not coat them with anything. The manufacturer suggested either foam or ceramic and I chose neither. I also gained about 15 gallons over what my maximum was before when I replaced them.

The work went well and was pretty straightforward. There were no surprises or other problems revealed. My old tanks were about 3/4 full which all had to be transferred, double filtered, and refilled.

The fill neck on the new tanks was smaller than on the old tanks, I am guessing a reflection of the new smaller nozzle size for unleaded fuel.

The tanks were about $800 each plus shipping and I paid my mechanic about $1,500 for the work which entailed removing my salon cover and all of the wood trim in the companion way and the door to the master stateroom to get them out and the new ones in. All-in-all it was a good deal and well worth it.

[prowlersfish]

I see no advantage of 2 tanks . If you run on one be bore you switch over as stated above you you end up with a lot of leaning to one side . I am surprised you have a 300 gal tank . The Tank I had filled most the space under the deck and it was only 150 to 175 gals .


you can lift the tank out with a fork lift like the ones they use to lift boats

[Surf and Sand]

I am surprised you have a 300 gal tank . The Tank I had filled most the space under the deck and it was only 150 to 175 gals .

I was quite suprised also, but I double checked. The tank is 28" x 38" x 68".

I really don't see the need for that size, and, I could use a fish box !

[gettaway]

two tanks any day,

contaminated fuel can be isolated, you can filter from one to the other, one can be a spare, if one leaks you have a back up, most likely will give you more usable space in the same area

[prowlersfish]

two tanks any day,

contaminated fuel can be isolated, you can filter from one to the other, one can be a spare, if one leaks you have a back up, most likely will give you more usable space in the same area

Don;t really agree , most folks would fill up both tanks at the same time so both would get bad fuel at the same time . if one leaks you should not run the boat so having a back up is useless . one 100 gal tank would take up slighy less room then two 50 gal tanks .

I don't think it really makes much difference some times you have to have 2 tanks or even 4 . My 36 could not have a single tank of any size unless I moved the genset forward to the engine 'room . a 45 viking has 1 tank aft of the engines (600 gal) a 48 post use 1 large tank between the engines and offer 2 aft as a option

[Jersdevil]

Mike. I have a 79 F30 Cleanmachine with two aluminum 70 gallon tanks (1 for each engine) I have the drawings for them I can dig them up this weekend, scan and send them to you. PM me if you would like them.

Hank

[aaronbocknek]

as a future tri cabin owner, i know that the fuel tank, one large one, is located under the center walk around aft cabin berth. is this a cause for concern? i believe that the tank holds 300 gallons of fuel.
aaron in baltimore.

[wuen]

Mike,
I have two aluminum 18x18x60 tanks from my clean machine, the hoses and fittings as well. If you are interested please Pm me.
Regards,
wuen

[Lawman]

I still have the original galvanized tanks (2 80 gal.) in my Clean Mashine that don't look that bad. Is it normal to have tanks this old? I'm told it's better than aluminum because they won't pit from the inside?????

[turtlem1969]

lawman- on my 74 tri-cabin I have all four original galvanized tanks, 2X80 gals and 2X40 gals, both are still in excellent shape inside and out.

[prowlersfish]

I still have the original galvanized tanks (2 80 gal.) in my Clean Mashine that don't look that bad. Is it normal to have tanks this old? I'm told it's better than aluminum because they won't pit from the inside?????

they will rust out from the insides