2011 - October 18th - Zenith Carby Upgrade - Stage 2 The Fitting

After 2 nights of  heated battle with man versus machine the carby is fitted, but there are several areas that require further attention, being:

* Fine tuning the linkages
* Connecting the hot air intake
* Connecting the crankcase ventilation
* Tuning the carby

Last night was a frustrating 4 hours in the shed after I discovered he Zenith is a lot longer in the throttle stroke than the Carter carby. I had to make several new linkages and luckily was able to adjust the length of others. Several years ago I converted the metal to metal carby linkages that had an enormous amount of slop to flexible rose joints. The end result is no slop and an instantaneous throttle response. ( I will cover this in more detail in a later posting)

I also had to fit a different choke cable and housing as the old one was too short for the Zenith.

The easiest part of the operation was bolting the carby on to the manifold.

At this stage I thought I would connect the fuel and see what happens. The Zenith is a very obliging set up in that it has three possible fuel inlet ports covering 3 sides. The fuel line is connected and I turn on the tap on the Vac Tank. Instantaneously fuel starts coming out the carby air intake. Turned off the Vac Tank, wiped up the fuel, tried again, fuel pissing all over the place.

I had a hunch that the internals of the carby had to be primed at which stage it would stop dripping fuel, otherwise I am in big trouble. So I turn of the Vac Tank and try to start the engine. Turned it over a few times, kicked but would not run. Tried again, the Red Chev fired up but would not rev past idle. Jumped out thinking I had to turn the vac tank back on, which as I did I noticed 2 plug leads were disconnected. There was no great miss, just a lack of revs. Try running your modern on 2 cylinders.

After putting the leads back on the Red Chev fired up, running very smooth. This was a complete surprise as I had not yet tuned the carby, I had no choke, and the engine was on full retard. Normally the Red Chev runs pretty average on full retard, so I can only assume that when everything has been set up right, this Zenith 14991 will be a big improvement.

There was no more fuel leaking after the engine started so my hunch about the carby needing to be primed must be correct, I don't really know, but she ain't leaking anymore.

I still have a few more hours of work to get the set up right, but even at this stage I am very happy with the results so far.