Anyone help? Beetle novice ahoy! Our bug runs badly until warm, then runs beautifully, you can see ice forming on the carb body, forming when the cold air rushes into the carb when revving. It will start and tickover, but drive off and it stutters. No problem once the engine is warm. There doesnt seem to be a winter setting on the air intake. Its our daily driver so needs sorting!

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Wayne

Here's some advice from Rick Higgins from Bug Me Video:

 

It sounds like the car is missing the preheater pipe to the carb aircleaner. Solving the problem you mention is it's primary function.
Without knowing the year that is about all I can offer.

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68autobug

Hi Martyn,

 

As Wayne suggested, Your inlet manifold is icing up due to the Fuel being so cold....  It seems You have the original carburetor etc,

so there will be a pipe going from underneath the carburetor to either side onto the top of the muffler...

Hot air goes from one side to the other...

thats if the heat riser pipe isn't blocked up... which they tend to do over 30+ years... 

most cars still run the original heatriser and Inlet manifold...

Mine was blocked up, I pushed some steel rope up there and kept twisting it until it went all the way thru.... and a lot of rusty steel fell out....

 

with some exhaust systems, the heat riser inlet heater doesn't work, because they were designed incorrectly...

My Son has exhaust extractors and the heatriser pipes are fitted, but don't work, as the pressure on both sides is the same....

There must be pressure on one side only, so the hot exhaust gases go across under the inlet manifold and heating it up...

 

in the first pic, the heatriser and inlet manifold are painted silver, and in the 2nd pic painted yellow...

You can see the pipe going to the RH side OK, but the fresh air hose blocks the LH side pipe...

 

You would need to take the whole inlet manifold/heat riser assembly off and clean it out or replace it...

also will need to replace all gaskets...

 

If You still have the VW original oil bath air cleaner, most had flaps which could be clipped for summer driving... [no heated air]

but as your car - is a late 1200 model, I'm not sure what air cleaner You have, but there should be a tube taking hot air from below the engine to the air cleaner, some air cleaners had two of these hot air hoses, depending on what country it was going to...

Early hoses were around 25mm and later ones 50mm same as the fresh air hoses on My engine.... 

My engine did have one 50mm hose going to the RHS of the carburetor.

I covered up the hole in the tinware so no hot air could come thru...

as We have the opposite problem in Australia... too much hot air...  lol..

 

cheers

 

Lee Noonan  

 

http://community.webshots.com/user/vw68autobug

 

 

Lee Noonan
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