Marcus sez:
> I adjusted the thumbscrew on the vacuum unit
> so that about 1/8in of thread was sticking out. Before I had about 1/3 in
> sticking out...i.e. it was very tight. The reason for this was when I had
> the distributor out, I was twiddling the thumbwheel, thinking to myself,
> 'I wonder what the hell this is for...oh well, can't be important'.
Yes, it is important, and I don't think it's been described quite
right yet.
This knob is what is known as a "vernier adjuster", or simply put, a
fine tuning knob for the dist timing. It lets you do final adjustment
without loosening the locking clamp/bolts.
This is another of those fun things you get to frob on your British
Car!
Why? Well let me 'splain a couple cases:
-You just got a tank of cheap gas, cuz that's all they had, and need
to retard the timing to avoid ping.
-You just got a tank of premium for the auto-cross, and need to
advance your timing to get a little power out of it.
In either case, you just lift the bonnet, and from the knob a few
clicks in the proper direction, as indicated by the A and R arrows on
the body of the dist. (A=Advance, R=Retard).
You should just set the vernier to the middle before you adjust your
timing via dist position, then you're all set for fine frobbing in
either direction.
________
/___ _ \ Roger Garnett (Roger-Garnett@cornell.edu)
/| || \ \ Agricultural Economics | "The South Lansing Centre
| |___|| _ | 3 Warren Hall | For Wayward Sports Cars"
| | \ | | | Cornell University | (Lansing, NY)
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