1981 mainship 34

[bigthaw]

REPLACE STEEL FUEL TANKS 1981 M 34 1, 200HP T6 354-4 Perkins range 4. 2600 hrs.
Can't do the work myself ...100 gal tanks port and starboard...new flooring access allows for better tank removal than factory stock...
how much cutting will be necessary? replace with baffled plastic tanks?? or....
aluminum probably...going to look at one with this problem...I figure $2000 ish to complete tank replacement, total..with labor.??
raw water jacket problems with this engine? parts obtainable??...vessel has been taken care of...engine is clean and maintained...original generator is done, throw away...a lot of refit work done by mature long time liveaboards...its clean and sound...east coast fl.
informed opinions appreciated...
Jeff in Holiday Fl.

 

[Keysdisease]

The tanks are aluminum, the original manufacturer is still in business and you may want to consider direct replacement. I can't remember the name right now but several Mainship owners have done this and will probably chime in.
Plastic tanks are certainly an option, but there is much to be said for a direct replacement when it comes to fit and plumbing connections, and they did last almost 40 years.
2K w labor is probably low, the labor is the big ticket.
Most of the tank replacements I have seen the engine is pulled, but access through the deck is certainly an option.
Can't speak to the Perkins except to say they seem to ne bulletproof.

Welcome to the dark side with a bunch of us ex-sailors, and good luck

 

[jleonard]

Yes tanks are aluminum. Any place that makes tanks can make replacements.
The guys I know that have replaced tanks have done so thru the floor. That's "just" carpentry.

I see that you are from Holiday/Tarpon Springs. I am in New Port Richey. I owned one of those for 14 years, if you have questions feel free to ask, I might even be willing to take a 5 minute ride to check out your boat.
Jay

 

[tumblehome]

tanks

Mine is a '79 MK1. I did port tank first and starboard tank when the port one was done. Pumped the fuel to opposite tank so they would be a manageable weight. I took up the plywood sole, simply screwed in place over each tank. I assume this was as the factory built it. I disconnected the hoses and wires and labeled them. I lifted the tank out by myself. The boat was on the hard, meaning the tank had to be lowered to the ground. I got my brother to help doing this. (He also helped put it back into the aft cockpit when tanks were ready to go back in.) I took the tank in my utility trailer to a local welder/fabricator shop. He determined each tank had some pin-hole leaks located in the bottom. Starboard tank was worse than port. The sides and top were still in excellent condition. He cut the bottoms off and replaced them with new bottoms. Then he pressure tested them. Price was about $350 for each tank. This was about 8 or 9 years ago. Working great ever since. It's important to install the tanks onto several plastic or hard rubber spacers that run the width of the tank. Something that does not trap water that could cause oxidation of the aluminum bottom. The tanks are secured in the tank bay using heavy steel banding. Important to duplicate this when re-installing.

 

[bigthaw]

tumblehome...great descriptive detail...Thank you ...really helps me visualize the work needed....

 

[Jeff F]

There's a good account of the project with pictures here: http://mainship34.com/fuel-tank-replacement/