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Liquid Gasket & Petrol.

3601 Views 3 Replies 2 Participants Last post by  Aduro
After reading the following feel more than free to call me a moron and a tool because for the most part your probably right, however this thread is here just to make sure no one makes the same mistake.

Had noticed lately that the gaskets on my float bowls were leeching the smallest droplets of petrol occasionally, i made a note to get around to getting new ones. however it kept manifesting int he back of my head that i was going to have a petrol leak that would come into contact with a hot engine at some traffic lights turning my beloved bike into a fireball (unlikely i know)
So thinking that this would be slightly more likely to happen after my engine was hot from the ride i had planned up old pac for today i thought i would shimmy up a quick fix to put my mind at rest til i got some new ones of Studricho. Grabbed a tube of Liquid Gasket from work (I supposed this was basically some form of rubber in a tube) Now i will add here that i took it out of the packaging and read the directions on the packaging, it was not til later i would find that the cautions were only printed on the side of the tube which i did not check after fully reading the packaging.
Took my float bowls off, removed the old gaskets and ran a decent sized bead of the stuff right around where the old gasket had been, it was getting dark as i finished so i reassembled and put the bike back together.

Get up for this mornings ride out and she wont start.
After much fucking around with the carb boots and several other things including a fucking hydrolock i had to take the plugs out for (fuck me i dont know how it happened either)
I finally take the carbs off and open them up, to my horror the petrol has reacted with the liquid gasket which clearly contains silicone or something turning it to a viscous goo which has proceeded to spread itself all through my carbs, over the floats in all the jets etc. Lacking any carb cleaner and any transport at this point i do my best to clean all the shit out with degreaser and scrape the hard stuff off with a screwdriver, the results were less than satisfactory. Replaced the old gaskets.
Upon closer inspection of my intakes on the manifold they are coated with a clear hair gel like substance that is obviously the silicone out of the goo that has made its way down into my intakes with the fuel most likely coating, clogging and generally fucking my valves while its there. I was unsure how safe it was to spray degreaser down there so i did my best to remove the goo with a clean toothbrush.
Around 4pm i finnally get her to fire up, shes running on three cylinders stall constantly and smells terrible.
I have 8am work start every day this week followed by evening tafe so i dont have time to fuck with her, will be borrowing mates car for the week to get to work and stripping the carbs right down on the weekend.

How safe is it to spray carb cleaner in my manifold intakes to break up any remaining goo?

For the love of god read both tube and packet as they are not always the same!!!
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What sort of crap stuff were you using? I use threebond RTV silicone for two stroke cases, it is fuel resistant. But you dont use gasket adhesive on float bowls at any rate, but im quite sure threebond would not do that shit.

I have made float bowl gaskets succesfully out of gasket card before.

Apparantly it is quite safe to spray carb cleaner all through your head if you need to, but i would turn it over a lot with the plugs out to try to blow all the crap out. Then try again with new plugs.

Personally i would remove the head and clean it out properly, but if your not up for that, just give it all a good blow out with carb cleaner, crank it without plugs to clear the cylinders then fit new plugs and do an oil change once you get it running for the love of god.
Also, you will probably find that gun wash does a much better job of getting the crap out of your carbs than anything else.

Don't apply that to anything made of rubber though and make ESPECIALLY sure that you remove your sliders before you start throwing anything like thinners around in your carbs and make sure the carbs are dry before you put them back.
To be honest i don't remember what the brand was but it was not high end shit I'm fairly sure and i cant check the tube as i tossed it over several neighbouring houses in an impotent toddler-like fit of mech-rage.

Mate doesn't need her car back for at least a month so gonna take this chance to completely strip down and clean carbs, possibly take the head off to clean it all out and change head gasket if it needs it. prob drain the oil, paint my cases and replace those seals to. Prob do a little reading up on valve clearances and see if thats within my comfort zone while the head is off.
What would you guys suggest for a general overhaul? up til now the bike has been my only transport so Ive kept my projects to a day and a half max.
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