My first post here and I would be extremely grateful to receive some of the wealth of knowledge evident in this forum.
I'm a JLR tech here in Thailand and have recently taken on a restored 73 S3 in need of setting up. I've plenty of experience with classics but the issue here is not knowing exactly what is original/modified/bodged from previous workshops.
So, the car was delivered to me running a bit lumpy, popping on overrun and definitely rich smelling. I decided the first thing to address were the carbs, so ordered a complete Zenith rebuild kit and a set of Magnecor plug leads.
Found several problems when rebuilding the carbs; dissolved bypass valve diaphragms, incorrect float heights, perished needle adjuster o-rings etc.
All rebuilt and refitted, carbs synced and mixtures set to 1 turn out from fully seated.
Engine starts easily from cold and hot, idles but spits flames from the carbs when revving. It didn't do this before but the timing and other settings may have been adjusted to compensate for tired carbs etc.
So I obviously need to check the ignition timing (any links to the procedure would be much appreciated) but before doing that, I need to make sure all vacuum pipes are in order.
Starting at right bank (drivers side). There is a single pipe joining both carb bypass valves together. Another pipe joins choke on front carb to a port above temp compensater on the other carb.
On the distributor, the vac advance (or retard?) unit is on the rear of the distributor body. There is a vacuum pipe from the advance unit with is connected by t-piece to the pipe that connects both carb bypass valves together on the left hand bank. It doesn't move when sucking the pipe.
Another pipe joins choke on one carb to a port above temp compensater on the other carb.
The rear left carb has a blocked off pipe underneath, rear of the float bowl.
Front right and rear left intake manifolds have a plugged opening.
Ignition amplifier is Lucas OPUS.
I renewed the plug leads one at a time so they are definitely not incorrect (unless they were wrong in the first place!).
It's already a lengthy post so I won't complicate it further, but if anyone things something is amiss from the above setup, or has any ideas, I would be super grateful.
Thanks in advance
