Removing a carb

Nathan Edwards /

I have a '79 Vespa Grande. I need to remove my carb so that I can clean it but I dont know where to start. Can anyone point me in the direction of a good tutorial with pictures and such. I have one that tells you how to clean it after its out but I need something that shows me how to get it out first.

So much thanks in advance. :)


Re: Removing a carb

Jason Luther /

its pretty straight forward when you look at it. loosen the screw or bolt that trightens it to the intake manifold. dont be worried about breaking anything by just taking it off. then follow the instructions that you have and take your time.-jason

Re: Removing a carb

Nathan Edwards /

So what about the line that connects to the upside down "L" shaped thing that comes from the carb? Do I take the wire off or take of the entire "L" thing?


Any good books that deal with repair? or a website?

Re: Removing a carb

Does that "L" thing relate to the throttle cable and the tube goes into the top of the carb? If so, it's probably internally connected .. not at all easy to describe how to remove it.

There are many diferent ways carbs are put together and without heavy doses of mechanical sense and common sense and a lot of care (and/or a specific guide), removal and disassembly can be a lot more painful than it need be.. Reasembly can be even worse without good record keeping of what went where.

Go HERE and pick up the vespa / grande manuals towards the bottom..

Re: Removing a carb

Remove center and right side cover

1. Unscrew the two screws on top of the carb and slide the entire throttle assembly up out of the carb and leave the spring and slide and cable attached to the carb top. Move the assembly out of the way to one side.

2. Loosen screw on air filter box clamp and remove the air filter. Careful there is a little round mesh screen that may fall into the engine area.

3. Remove fuel inlet pipe by removing the screw (leave the fuel line on it). Lift it up and out of the way. There should be a hollow cylinder shaped plastic filter and a round orange or red fiber washer under the fuel intake. Use a long blade screw driver to reach the filter and slide it up the blade to remove it from the carb.

4. Use a 8mm screwdriver type socket driver or an opened end 8mm wrench to loosen the nut that secures the carb to the intake manifold pipe. Use a little WD40 on the pipe to help slide and wiggle the carb toward the back of the engine. Remove the carb up through the engine compartment.

5. There is a cylinder shaped plastic shim that may stay on the intake pipe when you remove the carb or may come off with the carb. Either way you need to remove it from the carb to access and clean out the Idle Jet.

6. While you have the have the carb off and the fuel line open at the carb end, test your fule petcock switch in the UP (Reserve), Down (Full) and level or horizonital for OFF. You should have fuel flow in the UP and Down positions if you have enough premix gas in the tank.

Do steps 4 thru 1 to reinstall carb

Put in a new plug NGK B6HS gapped at .020" You can also use a B5HS.

Don't forget to also check the rear hub for oil. Takes 80-90 wt gear oil.

Good luck and let me know if you need any parts, I have a good inventory of New and used Vespa moped parts

Re: Removing a carb

Great description, Zippy!

I assume that the Grande and Bravo use the same lower frame?

Re: Removing a carb

Nathan Edwards /


Thanks for your help. I will surely be in contact with you when I need some quality parts. Thanks all others... I will be workin on this tonight.

Thanks all others as well. Your help (especially to a newbie) is so beneficial.

Another quick question:

With the throttle assembly, is the throttle line suppose to be able to come off? I have unscrewed the nuts as much as possible and cant get it off. Also, is there any issue with unscrewing and screwing the throttle line back in? e.g. certain amount of turns etc...



Re: Removing a carb

Sean Taylor 9/18/1971 - 1/14/2007 /

Yeah pretty much they do.

Re: Removing a carb

Leave the throttle cable intact with the top of the carb IAW Zippys instructions. You may want to try to put the throttle cable as close to where you found it as possible. I think it is used to adjust the idle.

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