• Hi Guest!
    If you appreciate British Car Forum and our 25 years of supporting British car enthusiasts with technical and anicdotal information, collected from our thousands of great members, please support us with a low-cost subscription. You can become a supporting member for less than the dues of most car clubs.

    There are some perks with a member upgrade!
    **Upgrade Now**
    (PS: Subscribers don't see this gawd-aweful banner
Tips
Tips

79 Midget Surges from 400 to 1000 RPM

startech47

Jedi Knight
Offline
My sons 79 Midget surges from 400 to 1000 RPM and back down. The cycle takes about 8 seconds. It has the single Zenith carb. Any ideas on what to check on the carb? The carb is completely stock and has the water choke on it. The surging occurs when the car is hot and has been run for several miles. The timing is set at 10 degrees before top deep center with a timing light and with the vacuum advance disconnected.

Also is there supposed to be foam on the temperature compensator to prevent rattling? This is part number 86 in the Moss catalog. It goes between the air filter and the stove on the exhaust pipe.

Thanks, Phil
 
Finally had time to work on the carburetor. There was gummy gas on the sides of the air valve and the needle had to be adjusted rich/lean. Have an even 800 RPM now. I'll re-adjust the timing tomorrow.
 
Back
Top