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Poodroo
09-12-2009, 11:56 AM
Just trying to find out how other fellow boaties out there are coping with their fuel tanks in this weather. The trouble I am having with my 25 litre plastic type fuel tanks has been the breather. My first tank the bleeder valve decided it would strip so that I couldn't close it off any more. After visiting Bias I found out that the only way to rectify the problem was to buy a whole new guage/sender unit which was going to cost in excess of $40.00. No way I thought because a whole new tank costs anywhere from $50-$80 depending on how good I wanted to go. I just couldn't see the value in spending $40.00 just for the new guage. So I ended up with a new tank and am keeping the other tank as a spare but the issue I am now having is in this heat I am finding the fuel expands to the point where fuel is still forcing its way out either through the bleeder or the fitting where the fuel line connects to the fuel tank. This makes me want to ask a couple of questions at least.

1/ Does undoing the bleeder to stop the pressure from building up increase the rate at which the fuel goes stale?

2/ The tank is being stored in my garage and in as cool a spot as I can. Is there anything more I can be doing to avoid these leaks?

3/ If the bleeder is left undone is there a risk of getting any moisture through condensation in the fuel itself?

Look forward to some helpful hints as I know I am probably not the only one who has these issues. Are stainless tanks any better? Thanks in advance.

Poodroo

Roughasguts
09-12-2009, 12:07 PM
#1 ......Yes
#2 ......Empty most of it in to the car or a jerry can.
#3 some... depends where you live tropical yes! woomera hardly anything.

Cheers

Aunty Jack
09-12-2009, 12:10 PM
I asked a Q the other week about leaving my fuel tank one 1/2 full and the other full in the boat, out in the heat, but with a boat cover on.
The results are miner evaboration no spillage with both breathers open!
when they were closed leaks and fuel every were.
So now i only close breathers when in transit to and from the boat ramp.

shanejohnson
09-12-2009, 12:27 PM
I leave the breathers fully opened all the time. In rain, sea water splash for 4 years no issues with anything. Suzuki original tanks, in an open boat where they cop everything. I dont know why people close them.

Noelm
09-12-2009, 12:37 PM
people close breathers when (say) you are filling up at the servo without the boat, you fill the tank (on the ground of course) then close the vent to transport it back home, so you don't get a car full of petrol.

lethal098
09-12-2009, 01:17 PM
dont leave the tank full, fill it up on way out fishing, the liquid will be constantly expanding and contracting with the heat and it will let off fumes which need to escape.

I had my breather block up on the boat and back out the deck filler she came and bye bye paint. i now no longer leave more than 2/3 tank in her.

cheers Lee

cormorant
09-12-2009, 03:02 PM
When storing them I put my kne on the tank so the sides indent a little and then lock off cap and breather. Do the same with jerry cans when filling to go bush ofr fuel transfer. They suck in a little when night and it cools but cope Ok and in the stinking heat that do not pop , weap or bulge crack seams as much.

It gives the tank the extra breathing / expansion room without loosing all the volatiles or allowing in moist air.

Some of the newer tanks are very flimsy plastic and I don't think will cope well with breathers closed and high pressure .

All tanks and jerry cans have a airspace built in to allow for fluid / gas expansion often the handle or bulge above filler level is that space . Never tilt the tank or fill it standing up so that space gets filled as the tank can split from the pressure.

Just kick in the sides or top like when you saddle a horse. Fuel under a slight vacume will do it no harm and better to keep all the good bits inside. It comes out of the bowser 10 deg cooler from underground tanks than the air temp at the best of times so you can adjust the pressure after the fuel has comemup to air temp where you are storing it . Filling 1l or 2l less is a 2 edged sword as it then has more air / gas inside and as temps rise the expansion is greater. Rarely see a full jerry crack but seen some very bloated half full ones in the hot sun ready to pop..

Scott nthQld
09-12-2009, 03:19 PM
I leave the breathers open all the time, except when other have said, when the full container is in transit. I also run the fuel through a fuel filter/water separator to remove any contamination.

Up here you don't really have an option when trying to store fuel, I have split plastic jerries and the plastic boat fuel tank from leaving the breathers closed when in storage. Now, i leave the breathers open, run a filter/separator, and if its more than a few weeks old (3-4 weeks usually) it goes in the car.

Chimo
09-12-2009, 04:06 PM
"Just kick in the sides or top like when you saddle a horse" a bit rough Corm!;)

I was more gentle with my horses, just used my knee.::)

Chimo

Poodroo
09-12-2009, 04:06 PM
Thanks for the good suggestions and information everyone. Would also like to take the opportunity to wish everyone a very happy Christmas and a prosperous new year to follow. Stay happy and most of all safe.

Cheers,

Poodroo

White Pointer
09-12-2009, 10:12 PM
G'day,

Risks - and this goes for plastic tanks and metal tanks with a welded seam, other than AS approved gerry cans.

Fuel expansion can split aged plastic tanks, bypass cap seals and damage cap seals. It can split the welded seams on 5L tins. That means a flood of fuel and that's very dangerous.

Cracking the seal will avoid the flood loss but still release fumes which are the explosive bit before the fire. If you do this make sure there is no electrical current of any voltage in the garage or shed. No fridges or freezers, no batteries left in drills or torches - no source of spark.

The best solution was suggested earlier. Pour it into the car and start with fresh fuel for each outing.

If you have a boat with a built in fuel tank, you may not be much better off. The boating standards in Australia are crap because of poor regulation. Boats with built in tanks should have an expansion canister, just like your car. Evaporative losses during refueling are a major cause of transport emissions and your vented tank on the boat just makes the problem much worse.

I have a 250Lt tank in my boat and filled it a few weeks ago. Not much was used because of the weather and every afternoon in this latest heatwave the fuel smell at the transom near the vent is incredible, and I think avoidable. Now, that's a project.

Regards,

White Pointer

oldboot
09-12-2009, 11:49 PM
Ummm, how far are we filling this tank.

If you look at the side there should be a maximum fill line.....this is to leave an air space at the top of the tank.

If you fill the tank FULL......I am not surprised that you are getting liquid escaping.

Petrol can expand quite a lot.

cheers

Damned67
10-12-2009, 12:31 AM
Here's my question:
In this heat, with the vent open, how much of our volatiles/combustibles are we losing from the mix?

I've only just recently started storing my 25l tank with the vent open, and the last couple of trips I've had issues starting the engine (mostly keeping it running when cold).... I have been thinking that it might be due to a mix of fuel that's turned to crap. Although, I always top off the tank, which is usually half full, before launching???

If I had something else that could use the 2 stroke fuel, I'd dump the lot and start from fresh....