Common Cooling and Fuel
Carburettor Wear and Maladjustment
Symptoms
Rough idle, hesitation, poor fuel economy, rich or lean running.
Cause
The twin SU carburettors (chrome bumper) or single Zenith-Stromberg (rubber bumper) have numerous wear points. SU throttle shaft bushings develop play (causing air leaks), needles and jets wear, damper oil level drops, and the mixture drifts with age.
Fix
SU carburettors respond beautifully to a proper service.
New needles and jets ($30--50 per carb), new bushings if worn ($50--100 per carb), correct damper oil level, and careful mixture adjustment.
A well-set-up pair of SUs is a thing of beauty.
Cost: $80--200 DIY for a full service kit.
Cost mentioned in fix
$30$50Cost: $80
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