What is carburetor percolation..., How can I take care of this annoying problem Options

[nsr-jamie]

Hi, over here in Japan where it is much hotter and humid than the rest of most parts of the world. My car is a 1972 914-4 model that has been tuned up a bit with 103mm p/c, high can and big valve heads (48x38) and twin 40mm drla Dellorto carbs....in the summer time the car seems to run badly and when I stop the car for even a short time to run into the 7-11 and try to restart the 914 it sometimes is quite difficult to get it running again. I talked with my mechanic friend at my local air cooled VW shop here and he told me I was experiencing carburetor percolation which seems to be common on these cars or air cooled engines that are running carbs like mine. I did a bit of research and found nothing here on this site but a little bit on google....not really sure what carburetor percolation is but kind of sounds like the carbs are over heating from the engine heat. Are others experiencing this problem too and if so what are you doing to try to fix it. My shop mentioned special gaskets or spacers to go in between the carbs and manifolds to cure this problem...it seems to occur more here on this side of the planet cause of the humid and hotter weather compared to say back home in the US or Europe. I checked on the CB Performance site and could not find spacers.....any body have any input to add? Thanks and cheers

Jamie in Japan

[nathansnathan]

The Phenolic FI spacers are in the 1.8/ 2.0 elring gasket sets. It's a fun project to make your own, but I can't see going to great lengths to make these.

About the Dellorto whistle, I was saying I think it is a myth, as my Dells only make that noise when they aren't sealing right. CB doesn't make them anymore, like was said. I speculate that those gaskets were a cover up - the literature wasn't going to say, "now buy our gaskets which compensate for how badly machined our manifolds are", so they made up a story about the gaps that had to be filled by a proprietary gasket, when it is just the thickness of the gasket that makes the difference. -just speculating here as I have not tried the special gaskets. My Dells son't whistle, though, without them.

It could be there is some confusion between "Dellorto whistle" and "Dellorto Howl". Mine do howl impressively. (IMG:style_emoticons/default/smile.gif)