170 Montauk Replacement Fuel Hose

Repair or modification of Boston Whaler boats, their engines, trailers, and gear
bmat5
Posts: 54
Joined: Fri Feb 14, 2020 8:07 am

170 Montauk Replacement Fuel Hose

Postby bmat5 » Sun May 07, 2023 2:33 pm

Some years ago, I bought a 2005 170 Montauk with its original Mercury 90-HP engine using carburetors. The prior owner was an older gentleman who did basic maintenance on the boat and was diligent about using only non-ethanol gasoline fuel. Since acquiring the boat I've done quite a bit of mechanical maintenance and cosmetic refurbishment. I also use only non-ethanol fuel, and this boat used approximately every other the weekend during the summer seasons in New Jersey.

In the 2022 boating season the Mercury 90-HP engine began to exhibit intermittent stumbling, loss of power, and stalling. My research leads me to believe at minimum, this carburetor engine would benefit from more regular use. I keep fresh non-ethanol fuel in the boat and have changed fuel and fuel-water-separator filters regularly. Winterization includes stabilizer in the final run of the season and then removal of all fuel and draining the carburetor bowls.

Last season I replaced a fuel fitting on the 22-gallon Moeller tank and realized the fuel hose was becoming brittle. I should have previously given the fuel hose some attention as part of the boat's refurbishment. I'd like to replace the fuel line at my next opportunity.

My questions are as follows:
1) What is the correct ID for this boat and engine combination, 3/8 or 5/16?
2) It appears that A1-15, Trident Barrier lined, or Shield series 368 are good choices. Additional input welcomed.
3) The boat is presently shrink wrapped and away from my reach. What length of hose is required?
4) Installation tips and advice is also welcomed.

Thanks

jimh
Posts: 11725
Joined: Fri Oct 09, 2015 12:25 pm
Location: Michigan, Lower Peninsula
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Re: 170 Montauk Replacement Fuel Hose

Postby jimh » Mon May 15, 2023 10:07 am

bmat5 wrote:What is the correct ID for this boat and engine combination, 3/8 or 5/16?
For 90-HP either one will work.
bmat5 wrote:It appears that A1-15, Trident Barrier lined, or Shield series 368 are good choices.
Any USCG rated hose will be ok. You do not need the A1 rating for hoses running outside of closed compartments. On an open boat you can use B1-rated hose.
bmat5 wrote:What length of hose is required?
You should measure yourself rather than rely on advice from others for this dimension.
bmat5 wrote:Installation tips and advice...
Use proper clamps to secure hose to fittings. Nylon circular ratchet clamps are useful. Oetiker clamps are useful. Worm-screw clamps are not as elegant but will work.