dellorto blow test question

When I performed the blow test on my dellorto 14 12P, how easy is it supposed to be to blow through the feul line? My float works properly because with the carb upside down I cant blow through it at all. But right side up it is really hard to blow through, and that's after 2 cleanings. Is there supposed to be some resistance there, or is it supposed to be really easy to blow through?

Re: dellorto blow test question

The hole is pretty damn small. That would make it hard to blow thru.

When you had it apart did you squirt carb cleaner thru it? And when you squirted it did it come out the other end?

With the float bowl off and the fuel line hooked up and the tap turned on, does the fuel flow out of the float jet?

Re: dellorto blow test question

carb cleaner came out everywhere I sprayed it in, so I should be good there. I didn't try taking the float off. Isn't there some adjustment in that needle that the float pushes down--I didn't want to mess anything up as I've never had to remove a float before. Is there any trick to it?

Re: dellorto blow test question

sorry, misread. Thought you meant take the float off instead of the bowl. Yes, feul flows through with the bowl off. Still acts like it's flooding the carb though.

Re: dellorto blow test question

OK, with the bowl off turn the fuel on and with your finger gently raise the float. The fuel should shut off completely.

To remove the float take a small screwdriver and press the float hinge pin to one side. When the pin sticks out far enough to grab with a pair of needle nose pliers grab the pin and pull it all the way out. The float and float needle will fall out.

There is no adjustment for the float level.

Check the float for leaks. Sometimes if there is a leak there will be fuel inside the float. Or try this: get a container of warm tap water and completely submerge the float in it. The air inside the float will expand when it is warmed up and if you have a leak you will see bubbles coming from the float.

Also, get a magnifying glass and look closely at the tip of the float needle. It should have no marks on it other than the concentric ring where it seated into the jet. Very seldom is there a problem with the float jet as it is brass and the needle is soft. If the needle is suspect, replace them as a pair.

Was fuel leaking out of the carb when the tap was turned on?

Re: dellorto blow test question

thats exactly what I needed to know, thanx alot. I am at work so I cant do that now, but I'll bet my float is bad. Just bought this moped last night and dinked with it for about 15 mins. Guy had it running great last week, then it sat for a week, now wont start. Removed the feul filter on the carb and it was totally clogged with orange tank dust. Cleaned the shit out of the carb 2 times, so I hope it works when I get back home and try to start it. The float didn't have any fluid inside of it. And I have a new plug and great spark.No gas wasn't leaking out the bowl with the petcock on, but the ped still seems like it's just getting flooded right away. Thanx for the help.

Re: dellorto blow test question

That doesn't make sense. If the float bowl was dry, it couldn't be flooded.

With the carb filter screen cover off open the fuel tap to see if you get a solid steady stream of fuel out of the tank/tap.

Did you remove the fuel tap and clean the screens that are up inside the tank? Be careful taking the tap out. If the bottom of the tank is all covered in rust scale it can trap the screens and you will tear them up when you pull it out.

On your bike can the tank be removed from the bike? If so, drain the tank, take it off the bike, and wash it out with soap and water then try taking the tap out.

Last thing: When running the bike make sure that the air filter is on it. The bikes and carbs are very sensitive in regard to air/fuel ratio that depends on the filter being there.

Re: dellorto blow test question

I meant that there is no gas INSIDE the float itself, the carb bowl will fill up just fine. When I pull the gas line off the carb and open the petcock it flows fine. I do need to kreem my tank. Right now I have 2 feul filters on it, so that should cover it for now.

Re: dellorto blow test question

Ben Van Zoest /

Why are you doing this fascinating "blow test" count me as ignorant.

Re: dellorto blow test question

to see if the float in the carb is functioning correctly, or if it has any leaks.

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