Thick green gunk/varnish in carb!

[sprint]

My RGS had been laid up for around 18 months or so. Had drained the carb by there was some unleaded petrol in the tank.

Last week I got it ready for the road and after turning on the fuel it started after a couple of kicks. Did a 50/60 mile run without any problems.

Left it for a couple of days and then started it again. No problem, but when I tried to pull away it would just die like it did not have enough fuel. Plenty of petrol though.

Had a look at it this morning and removed the float cover and pretty much everything inside was covered in a thick green oily sludge. However, once dried it is like a green varnish, see photo.

Have removed the carb and cleaned it but clearly the source is the tank?

Is this just decomposed petrol or something in the tank that has dissolved whilst standing as looking inside the tank I can't see anything that resembles the green gunk in the carb?

I am not aware of any lining in the tank.

So what do I have and what is going to be the best way to clean the inside of the tank which has recently been resprayed at great cost so whatever is needed needs to be done in a way that will not damage the paint?

Thanks

Andy

[berger]

i did go to the pub ,why spoil a habit of 40+years I had varnished jets after I left mine stood for a long time, this was some years ago. you can bet diamonds its the crap petrol we are being sold. since I've been using stuff called tetraboost {googly it} I've not had that problem even if I forget to run carb dry,,,, the petrol is........ well not petrol it is a lot of water absorbing ethanol which once made mine think it was a steam engine, you will see many moans about old petrol stood in your bike .... I did get some friendly comments about my betsy at cmc clay cross { chesterfield} old brit bike open day yesterday,,, then it was PUB time

[Butch (cb)]

Not the most attractive substance is it. I run mine on high octane (97 ish – and I’m thinking less/no ethanol) and Castrol Valve Master octane booster/lead replacement. I never run the carb dry and often leave the bike 6 months or so at a time. Not had a problem.

If there is a tank sealer giving problems then you should see that through the filler cap if you take a swap of the tunnel in there. I’d probably just drain the tank, give it a swill around with a pint or so of new stuff. And then try again with an all new refill.   

[ellis]

I don't have a problem with ethanol in the fuel. I always take a two gallon fuel container and fill it with the highest grade of fuel I can find. Back home I take the ethanol out of the fuel so don't have to keep draining the tank and carbs. Remember ethanol is hydroscopic so will attract any water vaper that is in the fuel system. Works for me.   

ELLIS

[muskrat]

G'day Andy.
My first thought would be some sort of tank liner (never seen a green one), ethanol can eat a couple of the older type (Kreem, but it's whitish). The top of the tunnel may be clear as it gets washed off first. Scrape around the bottom of the tank.
Ellis, never thought of separating ethanol out. Lucky down here to get ethanol free fuel. Seems like a lot of work and what if you need a few fill ups on a long trip? https://www.wikihow.com/Remove-Ethanol-from-Gas
Cheers

[chaterlea25]

Hi All,
Dunno about the green crap shine a strong light into the tank for a look see
I have seen petrol tubing dissolve leading to blocking up the carb

If you remove the ethanol from the so called petrol it will lower the octane rating

John

[sprint]

Thanks for all the  replies.

Have swilled around the petrol and emptied what was left in the tank. Poured some fresh in and drained that.

Then removed both taps, see photo. Both copper filters have dissolved, no doubt adding to the green gung in the tank?

How on earth are petrol companies allowed to produce and sell such stuff?

Not sure what to do. Will replace the taps and filters but clearly it is only time before the same happens again? 

Have several bikes but this is the first time that I am aware of this problem?

[Greybeard]

I was about to suggest that someone may have put a green jelly sweet in your tank.

[chaterlea25]

Hi Sprint
So the green must be some form of copper oxide or sulphate? what dissolves copper ?
You could make some filters from stainless mesh ???

There was a big news item in Dublin today where 50 plus vehicles were damaged by bad fuel 

John

[sprint]

Hi Sprint
So the green must be some form of copper oxide or sulphate? what dissolves copper ?
You could make some filters from stainless mesh ???

There was a big news item in Dublin today where 50 plus vehicles were damaged by bad fuel 

John

Strong possibility that the green is the copper oxide produced from the filters dissolving.

Have ordered a couple of these with nickel plated bodies and st/st filters:

https://www.ebay.co.uk/itm/Round-Lever-Type-Fuel-Tap-with-Filter-Nickel-Plated-1-8-x-1-4-WW73083N/332231421183?hash=item4d5a892cff:g:FacAAOxy0rZRGQF8

Will see how they get on.

[duTch]

 sprinto- can you keep us posted how they go ?
   I'm on the look out for good taps to replace my gas-cocks (actual gas- tapered threads= not-so-good) 

[Black Sheep]

Sprint, what petrol have you been using? I stick to BP ultimate with the bikes and have had no problems, not even with brass taps and copper mesh filters. If the bike was stored in a damp shed, possibly condensation could have entered via the breather. The one time I left a Land Rover standing with cheapo unleaded in the tank, the fuel pipe dissolved, spraying petrol all over the engine, including HT leads. A trifle worrying. Now everything gets posh petrol.   

[RogerSB]

Sprint, what petrol have you been using? I stick to BP ultimate with the bikes and have had no problems, not even with brass taps and copper mesh filters.

Yep! Another interesting topic - using modern petrol in our historic vehicles and I must admit it's something that concerns me, especially not being too clued up on it.

For my 1960 GF I've always filled up a 4 gal can at our local Asda but only after adding Redex Lead Replacement and Redex System Cleaner to the can beforehand and then I top up my bike's tank from that - hoping it does some good.

I have a BP station within a short drive away so, after what you say, I think I'll start using BP Ultimate instead.

Black Sheep, Do you add anything to the BP Ultimate?

[Greybeard]

I usually fill up at our local Sainsbury's supermarket  with their Plus brand. I'm not a high mileage or hard riding rider but everything so far seems OK.

[chaterlea25]

Hi Andy
Those ebay taps are quite fragile  the "stop" shears off easily
(that was the case with 2 sets I fitted 

The type of taps that were fitted benefit from the application of a little EZturn lube (petrol proof grease)
This keeps the taper nice and free for a year or so
A friend brought me a tin of the grease from the USA that should last several lifetimes 

John