Quick Tuneup
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I got a new timing light a few weeks ago and had set the
advance at 30 deg at 3000 so I completed the job today of a mini-tune
up. It took less than 30 minutes.
The timing light has a digital tachometer and up and down buttons the
control advance offset for the timing light. Another switch toggles
the timing light on and off if you want to use the unit for a remote
tachometer.
I use some blue nitrile disposable gloves like real mechanics use for
this operation. It helps to avoid greasy hands and shocks from the
running engine and a bit of added protection from skinned
knuckles. Will at CSP can send you a box of these.
First I took off the air cleaners. Then the oil cap so I could check
the molasses in the oil filler tank. The molasses is back after
cleaning it out last week.
I hooked the timing light unit up using the top connector on the
voltage regulator to get 12 volts and the body connector bolt just in
front of the regulator for ground. The top connector goes to the 12
volt connection on the generator. The timing sensor clips on the
number 1 spark plug , right side front. I loosened the locking bolt on
the distributor enough so the body could be turned. Leaving it in its
original position.
Then started the car and let it run until the engine would accelerate
smoothly and stay at idle. This didn't take long as the car was still
warm from its last trip.
The RPM was 700 according to the digital tachometer.
I did a quick check of the timing and it was in the ball park. I'll
check again after the idle, mixture and balance are adjusted.
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Then I checked the air flow into each of the
throats using an air mass flow meter called a 'Synchrometer'. Both
left side throats were at '5' and the right ones at '4'. I popped off
the bottom right carburetor linkage so the two sides are independent and
increased the idle slightly on the right side which brought the right
side air flow to '5'. (The units are kg/h).
The idle increased to about 720 RPM. Reconnected the throttle linkage.
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Next, starting on the right I screwed in the
mixture control on each throat until the RPM dropped according the
digital tachometer then ran the screw out again until maximum RPM was
achieved. This was about a half to three quarters of a turn. After
doing this on all 4 throats the RPM was up to 760 RPM. Using the
digital tachometer seems to provide finer control on the mixture adjustment.
A regular stubby screw driver was too long to adjust the mixture set
screws on the side of my Solexes. It bumped into the longitidinals. So
I adjusted the length of the handle with a saw and now it works fine.
Next checked the timing which was 29 deg at 3000 RPM. I increased by
one unit to 30 degrees advance and then twisted the distributor a bit
to recenter the mark shown under the timing light. The idle is now 2
deg advance. The important thing is to set the 3000 RPM value. You can
not adjust both the idle and the highspeed value, but only one or the
other. It is best to set the high speed value. Duane Spencer is
recommending 3000 at 30 degress and that seems to work fine with my
car. There is no additional advance above 3000 with my distributor,
but others may increase a couple of degrees. I reved the engine to
4000 to see that it still does not change between 3000 and 4000
RPM. This timing light can be propped on the engine mount cross bar so
you don't need three hands, one each for the throttle, distributor and
timing light.
I did not check the dwell or condition of the points because my cat
has a Pertronix electronic ignition and there is little practical
adjustment required.
About this time Asha got home. "What's wrong with your car?" .
"Nothing, I'm just checking the timing", I say. "Oh, you are playing",
she says. "Hey, this is important work". "Playing", she repeats.
"Have you hung those pots in my bathroom?", she asks. "No, I've been
working all day and I'm just taking a break and playing with my
car...".
She has a lovely smile.
Final check of timing, mass flow values and idle, shut it down and
button it back up.
The timing light was about $100 at Kragens. They also have a fancier
one that also measures voltage and dwell.
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Last modified: Sun, 09 Mar 2003
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