Water in my engine (possibly).

Hi all,

Around my area there has been A LOT of rain and hail in the past 24 hours, and when I discovered it wasn't raining this morning, I decided I would go for a ride. But first of all, I will say that I had put an old (petrolly -a new word) rag over the engine because the rain was somewhat horizontal and so I didn't want my engine to be absolutely dripping in water -not that that matters. But anyway, when I went to go for a ride this morning, I took off the rag and discovered that the carby was dripping wet with water. My question is: Is it safe for me to try and start the engine? or will I have to take off the carby and pull it apart and allow it to dry (which I don't fancy doing)?

Well first of all, I tried starting it up and it's still going fine. But secondly, I noticed that the place where the bike was parked overnight was smelling of petrol. So I opened up the tank, and sure enough, half the petrol had disappeared! I did leave the fuel tap on overnight accidentally, but I've done that before and never had any problems. But that leaves one question unanswered: How was all the liquid (whether it be petrol or water or both) getting out of the carby? My carby is one of the standard ones. I noticed that the top of the primer button was covered in bubbles of something, and after I wiped it off, those bubbles started forming again after just a few minutes. Well, while typing this, I think I've worked out what's happening.

First: The Disappearing Petrol. The day before this all happened, I had filled my tank up all the way (but not overflowing lol). I also forgot to turn the petrol off. I find this a bit unlikely, but it seems the only explanation I can think of, but I think that the increase in the amount of petrol in the tank caused I higher pressure in the fuel line, and because of this, the petrol will escape wherever it can: Namely, the small space between the primer button and the hole it sits in -hence the bubbles.

Second: Where did the Petrol Go? Well, the answer to that is quite easy. The bike had a bit of petrol around where it would have been leaking, but not much. And my bike was sitting over concrete. So, the petrol would have dripped on to the concrete, and evaporated in the sun -hence the smell of petrol around where the bike was... but shouldn't there be an oil stain on the concrete?

Nougat said:

Gasoline evaporates very quickly, and concrete is also fairly porous. Also, if the carb tilts towards the engine, the fuel will drain into the engine, too.

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My first thought was that the petrol would have gone into the cylinder, but like i said earlier, the engine started straight away. I'm simply amazed at how much fuel made it's way out of the tank -it was about 3/4 worth!