Tank cleaning. Is this the world's worst job?

[Portholme]

I noticed flakes of varnish being pulled through to the inline filter a couple of weeks ago and today I set myself the job of cleaning out the tank. That could have been my first error! I pumped out 100 litres of fuel in to jerry cans and could not believe how much varnish there was in the tank.

The pieces were ranging in size from a couple of mm across to 7 or 8 mm across and I pulled out several hand fulls.

I have got all the loose pieces out but there is still quite a lot stuck to the tank. Has anyone got any experience on doing this and if so how best to get the rest of it out? Ideally I would like to dissolve it as I can't take the tank out as it's under the deck.

Second question, what do you use to seal back the inspection hatch? It's got a rubber gasket but it is very nasty and needs replacing.

[Nos4r2]

I made a new one for mine out of nitrile rubber, and yes it's an awful job!

[Festinghouse]

i tend to drain my tank at the end of the season, leave the cap off so as to vent the tank and let it dry out. i can then poke a stick into the tank with some inverted duct tape on the end to pick up all the bits of paint etc - in my case the lining of jerry cans.

[Portholme]

Just bought the nitrile rubber on eBay for the princely sum of £1.25! Nos, how have you cleaned tanks out before? I'm planning on trying to dissolve it with some fuel and quickleen mix, scrapers to lift loose bits and possibly something like a scouring pad to rub in conjunction with the quickleen mix.

[willk]

Is the varnish appearing as a result of increased ethanol in the fuel loosening old deposits? Just curious if this is an ongoing issue for petrol tanks?

[Nos4r2]

Originally Posted by Portholme

Just bought the nitrile rubber on eBay for the princely sum of £1.25!

Make 100% sure it's the petrol proof one-there's 2 grades IIRC.

Originally Posted by Portholme

Nos, how have you cleaned tanks out before? I'm planning on trying to dissolve it with some fuel and quickleen mix, scrapers to lift loose bits and possibly something like a scouring pad to rub in conjunction with the quickleen mix.

Wow, that sounds like yours is really bad. I've only ever done the inside of steel tanks and it's quite easy with a brass wire brush and some good clean rags to wipe the crap out.

[Nos4r2]

Just checked exactly what I used-it was this:-

VITON RUBBER SHEET GRADE A 10" X 8"pad 0.5mm,1mm,2mm,3mm,4mm,5mm,and 6mmthk | eBay

[Portholme]

I was under the impression that ethanol fuel is worse for varnish. I dont know what the back story is as I bought the boat last year but it only did 170 hours in ten years so I imagine it's ten years of evaporating fuel.

Got the fuel lines home yesterday and blew them out to find lots of pieces stuck in the pipes. It seems I'm lucky I ever got anywhere!

Will check the grade if nitrile!!

[Nightfisher]

Double filter the line (before getting to engine) for months after cleaning.

[davej]

We did our club tornado tank a few years ago by firstly cutting a 100mm hole in the top of the tank, syphoning all the fuel out and filtering it away from the boat and washing the tank through with buckets of hot soapy water, syphoning again and washing with just hot water.

Clearly you need to disconnect the fuel lines first and do the final dry with clothes etc

This worked well and no more clogged idle jets.

Good luck

Dave

[Portholme]

All done with both fuel conditioner and cleaner added. Behaved it self on sea trials and I also know exactly how much fuel is in the boat!

Not a job I want to do again in a hurry.