It's been a while since I've posted on here, indeed I may have asked this question before:-
Has anyone suffered from Gelatinous Green Gloop in their carbs: ? If so what is the solution.
It only happens when the engine is on my dinghy in the water, left for a couple of weeks and the sun is shining for most of that period (so hasn't happened for a while).
I've tried switching from the ubiquitous Quicksilver oil to a less upmarket Shell variety - no difference.
Over the years I've asked various oil industry technical bods - invariably answered in terms of 'not me guv'
Recently I cam across an article about fuel additives in general and saw a comment that the increasing use of bio-ethanol in petrol leached copper from fittings (some copper salts are green) and had a higher tendency for gumming stuff up generally.
When I had trouble with my posh new garden tractor, the salesman mentioned some 'snake oil' was effective in reducing fuel gumming. It's widely used in the garden business - where machines stand for long periods - just like my 'gull.
Any comments anyone.
On a similar tack, I'm running at 20:1 (later engine) and wonder whether in fact, because modern lubes are so much better than original straight mineral oils, it would be safe to go as high as 30:1?
Your comments please, ladies and gentlemen
Green 'gloop' in carburettor
Moderators: John@sos, charlesp, Charles uk, RickUK, Petergalileo
Re: Green 'gloop' in carburettor
Do you run the fuel out of the carb when you have finished using it, its hard to tell you what fuel mix to use as I don't know what Seagull you have, one late seagull runs at 50:1, so I would stick to whatever the recommended fuel mix is for your motor, modern two stroke or not.
I have seen tanks furred up like a Christmas tree inside, draining out the tank after use and keeping the cap off or loose should stop the problem.
I have seen tanks furred up like a Christmas tree inside, draining out the tank after use and keeping the cap off or loose should stop the problem.
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headdownarseup
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Re: Green 'gloop' in carburettor
i would start again from scratch.
CLEAN EVERYTHING THAT CONTAINS FUEL!
so start with the tank, then the fuel line and tap (dont forget the filter in the tap), then move to the carb.
"green goo" ????
is the oil that you're using green as well? (i'm using rock semi synthetic tcw 3 and that's green)
if, as you say, after a couple of months laying idle, the petrol will evaporate away leaving behind "green goo" residue.
gulls like clean carbs, they run a bit better after a good clean.
jon
CLEAN EVERYTHING THAT CONTAINS FUEL!
so start with the tank, then the fuel line and tap (dont forget the filter in the tap), then move to the carb.
"green goo" ????
is the oil that you're using green as well? (i'm using rock semi synthetic tcw 3 and that's green)
if, as you say, after a couple of months laying idle, the petrol will evaporate away leaving behind "green goo" residue.
gulls like clean carbs, they run a bit better after a good clean.
jon
Re: Green 'gloop' in carburettor
Hi, I've spent a reasonable amount of time around motorcycle engines, prior to acquiring my first seagul, so whilst I'm no expert I hope my knowledge might be of use.
You don't mention which oil you are using to lube the engine,but modern fuel (unleaded) is prone to vaporisation and evaporation of its volatile constituants, hence the less than appealing 'cat pee' type smell that eminates from fuel tanks after only a coupe of weeks. After a relatively short time small quantities of fuel i.e the bit left in the float bowl etc. will begin to break down and return to their base constituants - in our case this means 'gunge' and if left long enough solid varnish type material, in the vital parts of the fuel system! Whilst I admit that our engines are relatively modest in their design they still react in a negative manner to having crud pumped into them!
As has already been suggested, your best bet now is to strip, clean and flush the whole fuel system from the tank to the inlet port, paying particular attention to the carb and the jets. To avoid a simialr situation in future, either run the tank/float bowl dry and keep the engine in a dry atmosphere or keep the fuel tank half full with a fuel preservatie added. Out of the two, if you are taking the engine out of the water for the 'off season' then I would go for option one, as I said earlier modern fuel goes off very quickly these days and is better used day to day in a decent vintage motorcycle lol
HTH.
With respect Linden.
You don't mention which oil you are using to lube the engine,but modern fuel (unleaded) is prone to vaporisation and evaporation of its volatile constituants, hence the less than appealing 'cat pee' type smell that eminates from fuel tanks after only a coupe of weeks. After a relatively short time small quantities of fuel i.e the bit left in the float bowl etc. will begin to break down and return to their base constituants - in our case this means 'gunge' and if left long enough solid varnish type material, in the vital parts of the fuel system! Whilst I admit that our engines are relatively modest in their design they still react in a negative manner to having crud pumped into them!
As has already been suggested, your best bet now is to strip, clean and flush the whole fuel system from the tank to the inlet port, paying particular attention to the carb and the jets. To avoid a simialr situation in future, either run the tank/float bowl dry and keep the engine in a dry atmosphere or keep the fuel tank half full with a fuel preservatie added. Out of the two, if you are taking the engine out of the water for the 'off season' then I would go for option one, as I said earlier modern fuel goes off very quickly these days and is better used day to day in a decent vintage motorcycle lol
HTH.
With respect Linden.
Re: Green 'gloop' in carburettor
Linden,
Your advice ref avoiding old fuel being left in carbs seems very sound. I am never sure whether the amount left in the carb after switching the fuel off and letting the engine use what it can from the carb is a problrm or not. Any comments?
On another issue, but very much related to fuel. You might have read the FV Timing post, in which the ignition timing advance is the topic. As someone who seems to have experience of old bikes, and sounds as if you have some detail knowledge of fuel , I have a question:- With old bikes, do you use adjust the ignition timing to the original manufactures specification or is a different setting used? If the latter; why?
Thanks
Jeremy
Your advice ref avoiding old fuel being left in carbs seems very sound. I am never sure whether the amount left in the carb after switching the fuel off and letting the engine use what it can from the carb is a problrm or not. Any comments?
On another issue, but very much related to fuel. You might have read the FV Timing post, in which the ignition timing advance is the topic. As someone who seems to have experience of old bikes, and sounds as if you have some detail knowledge of fuel , I have a question:- With old bikes, do you use adjust the ignition timing to the original manufactures specification or is a different setting used? If the latter; why?
Thanks
Jeremy
Re: Green 'gloop' in carburettor
Thanks thus far, folks.
I always run the engine until it stops for lack of fuel, but that leaves a small amount of fuel in the bowl. Being on the Thames, I'm loth to tip the engine up to remove most of what's remaining (mark you considering what's already being tipped into the river, my contributions is of infinitesimal consequence). I can't get my head around how much gloop is generated by (say) 20 cc of fuel.
I'll progress now to the Snake Oil solution.
I always run the engine until it stops for lack of fuel, but that leaves a small amount of fuel in the bowl. Being on the Thames, I'm loth to tip the engine up to remove most of what's remaining (mark you considering what's already being tipped into the river, my contributions is of infinitesimal consequence). I can't get my head around how much gloop is generated by (say) 20 cc of fuel.
I'll progress now to the Snake Oil solution.