CONTINUOUSWAVE

A marine mechanic recently suggested that I install a fuel-water separating filter on my 1988 Super Sport 13 that has a 1987 Yamaha 40-HP two-stroke engine. I have been searching for the appropriate filter, but have had difficulty determining exactly what I need. Pertinently, there appears to be an aftermarket Attwood fuel line kit installed. Looking through the link below, it appears that they only use 3/8-inch lines:

http://www.attwoodmarine.com/store/prod ... its/yamaha

Jamestown Distributers suggested the following fuel filter kit:
https://www.jamestowndistributors.com/u ... ?pid=11818

However:

--The filter is listed as 9.9-inches tall with a required 1-inch under-bowl clearance I don't think there is enough clearance to place it anywhere on the stern portion of the boat.


--Do I need the "primer pump" included with the kit, or is the just another component that has the potential to break?

Does anyone have any other kits that they recommend that meets the 3/8"-inch line requirement and preferably with a clear plastic bowl with drain? I am just assuming the 10 micron filter is optimal.

The RACOR model 490R-RAC-01 filter suggested in your hyperlink to a vendor is the gold-standard for marine fuel-water separating filters. This particular model includes an integral fuel line primer bulb. If your present fuel line assembly includes a primer bulb, having two primer bulbs, one on the filter and one on the hose, will not be necessary and will not be desirable.

For a 40-HP engine the likely maximum flow rate of fuel will be 4-gallons-per-hour. To install a filter with a maximum flow rate of 90-gallons-per-hour will be excessive. The filter capacity is twenty-five times greater than the flow rate for your engine at maximum throttle.

Since the particular model filter you have proposed to buy in the hyperlink to the vendor is a poor fit, has twenty-five-times the maximum flow rate capacity, and likely duplicates the primer bulb, selecting this option is not a particularly great choice.

SlightlySalty wrote:...any other kits that..meets the 3/8"-inch line requirement...

Use of fuel hose with a 3/8-inch inside-diameter is generally not necessary for an engine with a maximum flow rate of 4-gallons-per-hour. You can use a smaller, 5/16-inch inside-diameter hose if you wish.

You don't need a "kit" to install a fuel filter. Typically you will just install the fuel filter in the existing fuel hose line. The filter should be installed upstream of the primer bulb. The primer bulb should be close to the engine.

A RACOR filter of smaller GPH capacity will be a good choice. For example:

RACOR 120R-RAC-01 Spin-On Fuel Filter/Water Separator, 30 GPH, 10 Micron
Vendor: WEST MARINE:
https://www.westmarine.com/buy/racor--120r-rac-01-spin-on-fuel-filter-water-separator-30-gph-10-micron--1930445

The manifold above the filter accepts the standard 1/4-NPT threaded fittings. Choose HOSE BARB fittings to fit your existing fuel hose. You can order the hose barbs with the filter or find them at an automotive parts store or buy some from Amazon. To locate a vendor use the search term "1/4 npt hose barb" and add your favorite vendor name.


The physical size and filter capacity of the RACOR 120R-RAC-01 are more suited to your application.

More important than a fuel filter is treating your fuel with a stabilizer product at every fill-up. Sta-bil and all engine manufacturer's have a branded product. Take your pick.

A fuel filter is recommended if you frequent marina's, floating fuel docks, barge fuel stations or a land based fuel station that have low quality infrastructure.

For low horsepower, I would suggest something a bit less excessively sized. This is a RACOR filter with a lower profile and 25-GPH capacity.
https://www.jamestowndistributors.com/userportal/show_product.do?pid=6446

I advise checking with the outboard engine manufacturer regarding fuel line size. I was very surprised to find out that the Evinrude 60 E-TEC fuel line specification is 3/8-inch ID. I fully intended to use 5/16-inch fuel line when I installed the engine new until I consulted my dealer.

The 60 E-TEC is the same engine block as the 40 E-TEC. I wonder if the 40 E-TEC requires 3/8-inch fuel line? I couldn't find anything definitive via a quick internet search.

Rich

RICH--thanks for the note regarding the E-TEC engines. Perhaps Evinrude is just being prudent in requiring 3/8-inch diameter fuel lines. Evinrude might not even offer any 5/16-inch-ID fuel lines in their product or parts lines, so 3/8-inch is used.