Fuel Inlet Filler Cap

Repair or modification of Boston Whaler boats, their engines, trailers, and gear
mikegcny
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Location: NOFO New York

Fuel Inlet Filler Cap

Postby mikegcny » Tue Apr 27, 2021 12:04 pm

Where can a replacement fuel filler cap for my 1984 OUTRAGE 22 be purchased?

fuelFillerCap.jpg
Fig. 1. The OEM fuel fill fitting
fuelFillerCap.jpg (2.28 KiB) Viewed 3107 times

The fitting has a square housing. I only need the cap. I do not want to replace the entire housing unless the replacement part is a 100-percent match to the original part. The replacement cap does not need to be OEM; the cap replacement must fit the hole size and thread pattern.

jimh
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Re: Fuel Inlet Filler Cap

Postby jimh » Tue Apr 27, 2021 12:17 pm

The fuel fill fitting shown in Figure 1 is a bit unusual; it appears to have a black plastic fill cap. I would have expected the OEM fuel fill cap to be metal. On my c.1990 Boston Whaler boat the fuel fill fitting cap is metal.

Replacement fuel fill fitting caps are available from Sea Dog; a link to a typical vendor is given below:

https://www.go2marine.com/Sea-Dog-Repla ... ment-Chain

You should measure the thread size and pitch of the existing fitting in order to know what replacement size and thread is needed. A typical thread appears to be 1-1/4-inch diameter and pitch is 11-1/2 NPSM; N means National; P means Pipe; S means Straight (no taper); M means Mechanical

You can also find plastic fittings at a local store. For example:

https://www.lowes.com/pd/Charlotte-Pipe ... ng/3699170

Buying one might be a simple way to determine the proper pitch and diameter.

Be sure to buy a fitting that is rated for use with gasoline and gasoline-ethanol blended fuels.

jimh
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Location: Michigan, Lower Peninsula
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Re: Fuel Inlet Filler Cap

Postby jimh » Tue Apr 27, 2021 12:42 pm

Another quite reasonable option: call Twin Cities Marine in Wisconsin.

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Phil T
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Re: Fuel Inlet Filler Cap

Postby Phil T » Tue Apr 27, 2021 1:23 pm

It could also be a Perko cap.

From the Perko catalog:

PerkoFillCap.jpg
PerkoFillCap.jpg (88.01 KiB) Viewed 3087 times
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