Cleaning an old tank out

Stigomery · 15 April 2016, 10:06

Is there a recommended way to clean out an old pre-mix 2-stroke portable tank and make it nice and clean for use in a new 4-stroke motor?

Don't want to go ruining my new motor with some old crud from an old tank.

Thanks

Stig

Fenlander · 15 April 2016, 10:34

Cif/squeezy/degreaser as needed on the outside to match your shiny new outboard... swish round with a litre of new fuel inside if it has any signs of debris.

If as I assume the pickup boss unscrews from the tank I'd pop that out and see if there is a pickup gauze to clean. Also check the pickup pipe is well secured to the boss. On old tanks the pickup pipes have been known to drop off falling in the bottom of the tank leaving folks with a puzzling stopped outboard at sea so it's worth checking.

If you have any concerns about tiny remaining bits of debris just put a simple cheap disposable inline filter immediately after the pipe comes off the tank boss... one with a see through casing so you can see if there is any dirt.

Stigomery · 15 April 2016, 11:25

Ah cool - thanks Fenlander. This type of thing:

PETROL 6MM FUEL INLINE FILTER QUAD MINI MOTO PIT DIRT ATV MOTORCYCLE BIKE | eBay

Fenlander · 15 April 2016, 11:36

Yep that would be great.

I'm was wondering about an inline water separating fuel filter (£50+) somewhere in the tank line... but given that we can be so clean with just neat fuel and keep it rotated with spare going into the car after each run so the outboard is always running on fresh I don't think I'll bother.

Stigomery · 15 April 2016, 12:03

Quote:

Originally Posted by Fenlander

I'm was wondering about an inline water separating fuel filter (£50+) somewhere in the tank line...

When you mentioned this before I considered doing the same... i was always puzzled "why" though - per my other comments about garden equipment never having had a problem in 20 years of, well, neglect and crappy fuel.

Is it down to condensation? Or water ingress from just being on the water? or?

steco1958 · 15 April 2016, 13:43

Quote:

Originally Posted by Stigomery

Is there a recommended way to clean out an old pre-mix 2-stroke portable tank and make it nice and clean for use in a new 4-stroke motor?

Don't want to go ruining my new motor with some old crud from an old tank.

Thanks

Stig

Unless there is gunk in that tank I wouldn't bother cleaning that . Just simply add the petrol and run

Poly · 15 April 2016, 16:32

Quote:

Originally Posted by Stigomery

When you mentioned this before I considered doing the same... i was always puzzled "why" though - per my other comments about garden equipment never having had a problem in 20 years of, well, neglect and crappy fuel.

Is it down to condensation? Or water ingress from just being on the water? or?

It's certainly possible that if you take a big wave some of it can find its way into the tank via the vent screw.

Of course if you fill at sea from Jerry cans then rain or sea spray is a risk.

If you use dockside fuel there is often a poorer reputation and so a risk.

I'd say condensation is only a big issue if you store tanks (part) empty.

However, if you have good "fuel hygiene" and keep an eye on what is actually inside your tanks then with portables in a sib I think you need to be unlucky to fall foul of enough water in your fuel to cause you trouble. Life may be worse with modern injectors and at the cost of fixing those a filter may be worth it?

Poly · 15 April 2016, 16:35

Oh, and I should point out my thoughts on that apply in the UK where most petrol is dug out the ground. If you live in a country that hasn't realised you are supposed to drink alcohol not burn it, then your risk of/from water may be different.

jeffstevens763@g · 15 April 2016, 18:59

The minute amount of oil left won't hurt the four stroke at all its debris that will suck them out with the Hoover when the petrol has been drained.then fit a fuel water separator you will have no probs then ever just clean out when required.

Cheers

Poly · 15 April 2016, 19:58

Quote:

Originally Posted by jeffstevens763@g

The minute amount of oil left won't hurt the four stroke at all its debris that will suck them out with the Hoover when the petrol has been drained.then fit a fuel water separator you will have no probs then ever just clean out when required.

Cheers

Combining an electric motor (hoover) and fuel tank vapour doesn't sound like a great idea to me.

I'd certainly want it more than just "drained" before sticking Henry's nose in it...

Fenlander · 15 April 2016, 20:36

>>> Originally Posted by Fenlander... I'm was wondering about an inline water separating fuel filter (£50+) somewhere in the tank line...

>>>When you mentioned this before I considered doing the same... i was always puzzled "why" though - per my other comments about garden equipment never having had a problem in 20 years of, well, neglect and crappy fuel. Is it down to condensation? Or water ingress from just being on the water? or?

My thoughts surrounded the increasing amounts of Ethanol being added to petrol which can allow water to be absorbed by the fuel to a greater degree... partricularly in long term storage where corrosion of fuel system parts might occour.

I've never really worried about it in the old 2-strokes as I believed the oil in the mix might negate any corrosion plus the smaller 2-strokes were quite basic in respect of carburation so not that onerous to give a carb clean.

However going to EFI with the Suzuki means finer and more expensive fuel system components so I'd wondered if they needed the added protection of an external filter.

However I decided to go the way of recycling unused fuel into the cars and running the outboard on newly bought fuel all the time.