MONTAUK Fuel Tank, Fuel Hoses for E-TEC

[kipkeller]

I'm re-powering my [1982] Montauk [17] with a 2018 E-TEC 90.

What type of fuel hose fitting goes on the fuel hose stub coming out from the engine hose and cable rigging grommet?

The fuel hoses on 12-gallon on-deck fuel tanks from Moeller, Attwood and Scepter all are too small. I believe Evinrude calls for 3/8-inch ID fuel line.

The boat’s old fuel hose is 1/4-inch ID.

What have others done?

[biggiefl]

I would not think a 90hp would require a 3/8ID hose. My 225 did. Are you putting in 2 tanks or just one?

[kipkeller]

I would like to go with two 12-gallon tanks and switch between them.

I may install a fuel-water separator filter.

What should be fitted to the engine’s fuel hose?
It has a barbed fitting for a 3/8-inch ID hose.

[biggiefl]

I would replace all the lines as you do not want to contaminate a new engine. If it calls for 3/8 then you need to buy 3/8 hose. I also would go with a single tank as changing them is a PITA and 12 gal tank is too heavy to carry for the most part. A single 18-24 would be my choice.

[jimh]

I have no survey information about what other E-TEC owners might have done.

What other owner’s have done is not particularly important in choosing the fuel system components for the new engine.

A new engine should be installed according to the manufacturer’s specifications.

For the Evinrude E-TEC 90-HP engine there is a comprehensive document called “Predelivery and Installation Guide.” You can download a PDF copy from the Evinrude website.

Follow their advice about fuel hose diameter.

If the engine is installed improperly the warranty coverage will not provide any benefit for damage due to improper installation.

My own advice would be to install an Evinrude 3/8-inch primer bulb at the engine connection, and use 3/8-inch ID hoses and fittings throughout the fuel system.

A fuel-water separating filter is a good idea.

Fuel starvation will damage an engine.

As for two 12-gallon tanks, you should realize the fuel savings of a modern engine will cut fuel used by half. Having 24-gallons aboard with a modern engine would be like having 48-gallons on an old Montauk—which would have been unheard of in 1982. Most used two 6-gallon tanks.

With 24-gallons aboard an E-TEC 90 will run at idle speeds for 125-hours.

The fewer connections, gadgets, valves, and gizmos in the fuel system, the more reliable the fuel system will be.

[jimh]

I am certain it must be possible to buy an on-deck fuel tank without having to buy a fuel hose, primer bulb, and fittings as a mandatory bundle. The larger tanks you are seeking are typically sold without any hose, fittings, or primer bulbs included as a bundle.

[jimh]

Many MONTAUK boats are using a Moeller white fuel tank SPECIFICALLY designed to fit under the Reversible Pilot Seat. The tank capacity is about 22-gallons. There are many prior discussions about this tank.

[Acseatsri]

I second the recommendation for the white Moeller 22 gallon tank. It fits perfectly under the RPS and because it's white, doesn't generate a lot of heat or expansion when the sun beats on it.

I don't think the water separating filter is necessary, but if you decide on one, place the primer bulb BEFORE the filter. That way if you do have water, you can open up the filter drain and pump from the tank until you get the water out.

[jimh]

Re where to install a fuel-water separating filter: again, I would follow the manufacturer’s recommendation. Often they specify their filter is to be installed on the suction side of any pump. A primer bulb is a manual fuel pump.

The recommended location for a primer bulb is close to the engine.

[kipkeller]

Thanks for all the advice. The Moeller tank looks like a winner.
I’m sure I’ll have more questions.

[jimh]

More information about the Moeller fuel tank is now the topic of its own thread. See

The MOELLER 24-gallon White On-deck Fuel Tank for Boston Whaler Boats
http://continuouswave.com/forum/viewtopic.php?f=4&t=5807&p=33778#p33778

[jimh]

Regarding fuel hoses, Evinrude has their own excellent fuel hose product. It is a rugged rubber outer jacket fuel hose, resistant to alcohol fuels. Watch out for older fuel hoses using a gray metallic outer jacket. They are notorious for having failed when used with ethanol-gasoline blended fuels; their inner hose liner loses adhesion from the outer jacket, collapses, and shuts off or severely reduces fuel flow.

Problem reported with E-TEC engines are often related to lousy fuel rigging that causes fuel flow restrictions and results in lean combustion. Do not scrimp of the fuel rigging with a new engine.

[kipkeller]

I am going with all new hose, tank and fittings. I'm kinda confused on a couple of things.

Evinrude recommends 3/8-inch ID hose. I am good with that.

All the fittings for the Moeller tank and the BRP filter-separator are 1/4-inch NPT. Does this make any difference?

Should the sequence be: tank, hose, filter-separator, hose, priming bulb, hose, engine?

Thanks.

[Phil T]

I place the primer bulb before the water separator to make re-priming after changing filter easier.

[jimh]

The "1/4-NPT" specifies the pipe thread, not the inside diameter.

Typically a fitting for a fuel tank hose would be a 3/8-inch hose barb with 1/4-NPT thread.

Example:

https://www.mscdirect.com/product/details/55539191

[kipkeller]

1/4” NPT has a 1/4” ID which is why I questioned having that and a 3/8” fuel hose. I have found an Evinrude dealer near me and will consult with him. Thanks for all the info and advice.