Risk of Using Old Polyethylene Fuel Tank

Repair or modification of Boston Whaler boats, their engines, trailers, and gear
Montauk2003
Posts: 25
Joined: Wed Apr 20, 2016 12:41 pm
Location: Lake Wylie, SC

Risk of Using Old Polyethylene Fuel Tank

Postby Montauk2003 » Mon May 21, 2018 9:55 pm

What are everyone's thoughts [about the risk of using an old polyethylene fuel tank?

I am not sure what risk there would--especially when using non-ethanol gasoline.

An [unidentified] marine mechanic told me that old fuel tanks should be replaced after [an unspecified number of] years.

BACKSTORY: I have two Moeller 6-gallon polyethylene fuel tanks I purchased about eight years ago. I am upgrading to a new Moeller 22-gallon tank. I was planning on keeping the old tanks and using them in another boat at some point in the future. Thanks --Danny

Lake Wylie, SC

jimh
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Joined: Fri Oct 09, 2015 12:25 pm
Location: Michigan, Lower Peninsula
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Re: Risk of Using Old Polyethylene Fuel Tank

Postby jimh » Mon May 21, 2018 10:07 pm

Montauk2003 wrote:What are everyone's thoughts [about the risk of using an old polyethylene fuel tank?
I don't have any particularly clear thoughts on your question, for three reasons. I don't know what risk you or the mechanic envisioned, I don't know how old your tanks are, and I don't know how many years the mechanic said they will last.

If the unspecified mechanic said to replace the older polyethylene tank after 100-years of use, I would tend to agree with him, even though the risk that is supposed to occur has not been identified.

What sort of risk do you thing exists specifically for a polyethylene fuel tank?

For Moeller 6-gallon polyethylene fuel tank?

In the case of a manufactured product, check the manufacturer literature or contact the manufacturer for advice on the expected service life.

I suspect that the service life of an on-deck fuel tank of 6-gallon capacity made from polyethylene will be very much affected by its exposure to ultraviolet radiation from the sun, and the location where that exposure occurs.

In the total cost of boating, the cost to replace a 6-gallon on-deck polyethylene fuel tank is so little that it cannot even begin to be included in any sort of financial decision about whether or not to go boating. If you are uncomfortable with a perceived risk, replace the tank. It can't cost more than $50.

Montauk2003
Posts: 25
Joined: Wed Apr 20, 2016 12:41 pm
Location: Lake Wylie, SC

Re: Risk of Using Old Polyethylene Fuel Tank

Postby Montauk2003 » Mon May 21, 2018 10:24 pm

Hi Jim: I was curious based on what the mechanic said, especially when he was not trying to sell me a new gas tank. The next time I see the mechanic, I will get the theory behind his thoughts. However, I have polyethylene tanks in the 15 year old range I use for my lawn mowers and never had any problems. My Moeller 6 gallon outboard gas tanks are about 8 years old so I will keep them on hand for another 10 years if not more.
thanks,
Danny
Lake Wylie, SC