Hot weather causing air pockets?HELP!

Hi, I have a moped that stopped working in the past 24 hours (I didn't change anything in that time period) . It had a huge air bubble in the fuel valve and was not getting any fuel. It had enough fuel in the tank but I went ahead and added more. I had an inline fuel filter on it but I took it off (it was only 30 micron, I'm getting an 80 micron soon) because I didn't know if it was restricting fuel flow. Now it just has the fuel valve on it and I got rid of the air bubble and it still wont run. When I try to start it, it seems like it will start but it never does, I took off some covering and watched to see if it was pumping fuel and it didn't seem like it was. I heard from a guy that sometimes hot weather (its been really hot where I live lately) causes a lot of air bubbles which makes it hard for the moped to start but I wanted to see if anyone felt differently and if there is anything I could do to fix it (the moped has new spark plugs too). I would really appreciate any advice.

Re: Hot weather causing air pockets?HELP!

If it i really hot and the engine has been running the carb. can get so hot that the gas in the float bowl can boil and vaporize. But, if it has not been running the float bowl should re-fill by gravity. The fuel filter should not have caused any problem.

If you disconnect the fuel line at the carb and then turn on the fuel, does the fuel flow?

What make/model 'ped are you running?

Re: Hot weather causing air pockets?HELP!

You may also have a clogged vent in your gas cap.

To find out, remove the cap when you see the bubbles.

Usually bubbles just mean out of gas, and switch to reserve.

Re: Hot weather causing air pockets?HELP!

Hi, well I disconnected the fuel line at the carb and when I point the fuel line down it flows pretty well it seems. I'm running a 1977 Sachs Columbia Commuter moped. It's got new spark plugs so I don't think that's the problem either. It's been 2 days since it last ran. I tried running it at night when it was cooler too and it didn't run either, just seemed like it wanted to purr but not catch. It's a little frustrating so I appreciate any advice.

Re: Hot weather causing air pockets?HELP!

I checked the gas cap and it seems to be fine, and I have a full tank of gas right now. I tried switching to reserve and nothing changed either. Thanks though.

Re: Hot weather causing air pockets?HELP!

Have you checked the spark?

Spray some carb cleaner in the air cleaner and see if it fires up. If it fires up then you have a fuel problem; clean the carb.

If it does not fire up you probably have a spark problem.

Hot weather causing air pockets?HELP!

is there a drain screw on the carb?

if there is remove it and see if the fuel runs free...

try a shot of starting fluid--that will tell you if it has a fuel problem.

and put your filter back on-- it doesnt take much to clog up those tiny little orffices in the 102sp had a clogged orffice--

after many hours of trying diffrent carbs --weedeater--old chainsaw

carb--i went back to the oregional--only to discover that it was just a clogged orfice that kept it from running!!!!!!!!!!

on my 102sp it sucks the fuel up from the bowl using the drain screw--it has a small hole in it which i thought was only for draining

purpose.RUNS FINE NOW...well almost just have to set the point gap--and throw some paint on it...think i"le put a bigger sprocket on the back and just use it on the beach when i take the motorhome out for a cruise.............uh what was the question ;}

Re: Hot weather causing air pockets?HELP!

Alright, I really don't know much about mopeds at all so I'm not too sure what the air cleaner is. If you could tell me where it was located and what it looks like I'll go ahead and do that. But when I do spray carb cleaner into it, is there anything I need to know about the technique? Thanks.

Re: Hot weather causing air pockets?HELP!

Just wanted to thank everyone for all their help. But I've been an idiot, it just needed a new spark plug. Now it runs like new. The reason I didn't check the spark plug was becase the spark plug is only 2 weeks old and has about 50 miles on it. But anyways, I am so glad. Thanks guys.

Re: Hot weather causing air pockets?HELP!

Brian Mikami /

Make sure you gap your plug to specs. If it fouled in 2 weeks, could be running rich...make sure your air filter is clean or replaced too.

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