Quick Tuneup

c3568 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.
030316-1807 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.
030309-1788 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.
Last modified: Sun, 09 Mar 2003


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