Cure for Vapor Lock


Vapor lock occurs whenever the carburetor gets too hot and the gas begins to boil. The result is that the bubbles prevent normal flow through the various orifices. The owner's manual suggests opening the carburetor door during these brief stops. This fix never really helped my scooter. Occassionally, I would ride with the door open to help cool the carburetor. This sometimes helped on cooler days.

The problem can be essentially eliminated by buying a replacement carburetor manifold from the Heinkel Club Deutschland. This manifold has a plastic bushing fitted. The bushing reduces the heat transfer from the manifold to the carburetor.

Of course, there are other issues that might be present. For example, you should verify that your timing is correct, the carburetor jets are correct, or you have an air leak somewhere. These conditions might cause hot running and won't be fully corrected by a new manifold

Tools Required:


Tough guy picture.

Remove rear body panel. The body panel is secured by two 10mm nuts under the seat and one 19mm bolt under the spare tire. Don't forget to disconnect wiring harness to rear lights and turnsignals.

Shut off gas. Since you will remove the carburetor, this is generally a good idea. Unless you like spilling gas on your garage floor.

Remove carburetor. Typically, the carburetor is held on by a 9mm nut. Loosen nut, and remove carburetor.

Remove carburetor side engine shroud. Loosen all 10mm nuts on the engine shrouds. Completely remove the 10mm nut on the bottom, center of the carburetor side. Carefully remove carburetor side shroud.

Remove carburetor manifold. The carburetor manifold is secured with two 14mm nuts. Remove these nuts.

Replace manifold and gasket. Install new gasket and updated manifold. Secure two 14mm nuts.

Install engine shrouds. Install the engine shroud. Tighten all 10mm nuts.

Install carburetor. Install carburetor and test for correct running. It is best to drive the scooter to warm everything up. Once hot, set idle and air mixture screws. You really shouldn't have to do this, but it doesn't hurt to keep on top of the settings.

Note: This page is not yet complete. Supporting photos will be added and the text will be completed very soon.



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