Fuel tank storage

Tonus · 14 January 2021, 10:09

Hi there - I’ve been storing my outboard and fuel tank inside this winter (running it in occasionally). I wondered whether I should keep the fuel tank’s vent screw open or closed while storing? When the temperature is warmer it lets off quite a bit of pressure sometimes... am storing in a garage that is pretty cold. Many thanks

Pikey Dave · 14 January 2021, 11:01

Quote:

Originally Posted by Tonus

Hi there - I’ve been storing my outboard and fuel tank inside this winter (running it in occasionally). I wondered whether I should keep the fuel tank’s vent screw open or closed while storing? When the temperature is warmer it lets off quite a bit of pressure sometimes... am storing in a garage that is pretty cold. Many thanks

Closed

Tonus · 14 January 2021, 13:04

Quote:

Originally Posted by Pikey Dave

Closed

Erm - thanks!!

treerat · 14 January 2021, 13:23

Closed, otherwise the vapours will escape and stink out the garage as well as lose the octane levels.

Pikey Dave · 14 January 2021, 13:25

Quote:

Originally Posted by Tonus

Erm - thanks!!

You’re welcome. If you leave it open, it will breathe & get condensation on the inside = water in fuel.

willk · 14 January 2021, 14:47

Quote:

Originally Posted by Pikey Dave

You’re welcome. If you leave it open, it will breathe & get condensation on the inside = water in fuel.

Poor lad - he asked a question and all he got was the Word of Dave.

The Wordy according to Poly might have been better received...

Pikey Dave · 14 January 2021, 15:03

Quote:

Originally Posted by willk

Poor lad - he asked a question and all he got was the Word of Dave.

The Wordy according to Poly might have been better received...

Aye, I answered the question. I didn’t see where it said “discuss”[emoji23]

Tonus · 14 January 2021, 19:19

Quote:

Originally Posted by Pikey Dave

You’re welcome. If you leave it open, it will breathe & get condensation on the inside = water in fuel.

Thank you for that gents - super new to this as is apparent!!

jeffstevens763@g · 14 January 2021, 21:22

Since I had water problems I changed my vent with a piece of fuel pipe as a gasket with a very small hole drilled in the side so I just nip it during cold no probs but in the summer the pressure in the tank can push through just saying.

Salty Pete · 15 January 2021, 00:40

At least he knows he has a vent

Unlike myself who went for a test ride in his brand new RIB to find that when he had finished his fuel tank was only 2/3 its size.

Tonus · 15 January 2021, 17:07

Quote:

Originally Posted by Salty Pete

At least he knows he has a vent

Unlike myself who went for a test ride in his brand new RIB to find that when he had finished his fuel tank was only 2/3 its size.

Hey thanks all for the extra info. I’ll keep it closed and half an eye on it.
Roll on the Spring! Thanks

jonp · 25 January 2021, 05:14

I keep a few 20lt plastic jerry cans inside the garage under the house, all with the valves lightly open. The reason we leave them open is because on warm days the can expand greatly, sometimes deforming the containers so much they almost look round. Never had any issues of condensation in fuel containers or underfloor tanks in 43 years of owning boats. I have a seperate fuel filter with a clear bowl water catch fitted each boat after buying them and like I say never had any water show in these catch bowls.

Before you jump on me saying you live in Australia where its hot, yes it is in summer and also cold with frosts and snow in winter.

Tonus · 28 January 2021, 16:45

Thanks Jon - I think I'll do the same as every time I go and check on the tank it has some pressure to release... even though it's very cold here at the moment. I left the tank on a floor with underfloor heating and it freaked out - super swollen!!

Thanks for the advice!

HDAV · 28 January 2021, 23:13

Every time you vent it you loose volatile elements, the most volatile first..... this means the octane rating of the fuel will fall, no often an issue but can be after a while especially if lockdown means the off season is extended, mix in some fresh before heading out and too late now but stabiliser added at end of season can help 20l isn’t. A big deal but 70+ can be a pain!

jeffstevens763@g · 29 January 2021, 09:50

car fuel tanks vent all the time!

HDAV · 29 January 2021, 23:15

Quote:

Originally Posted by jeffstevens763@g

car fuel tanks vent all the time!

So do petrol station tanks.......

Pikey Dave · 29 January 2021, 23:23

Quote:

Originally Posted by HDAV

So do petrol station tanks.......

Yes, but it’s not a relatively small amount of fuel sat about for months on end not moving. You only have to look at diesel fuelled boats to see the issues with water & sedimentation. My RIB has an inboard open vented tank, but I keep it full of fuel over the winter to reduce “breathing” & condensation. The portable tanks for the SIB remain sealed.

jonp · 30 January 2021, 05:26

Quote:

Originally Posted by jeffstevens763@g

car fuel tanks vent all the time!

As do boats. Often a boat fuel tank will undergo very large temperature changes because of extremely hot days and very cold nights and continually vent. Often some of these boats rarely get used but when they do they seem to run fine on the fuel that's in them.

According to the auto expert (well known highly regarded engineer expert) those fuel additives are a load of toss that people recommend!!!...he has lots of videos on YouTube just search under auto expert fuel additive or under any of the many other things he tests from tow lints to shackle break loads.