Update on state of tune and a question on turning over the engine.

[sdyck]

Well I've owned my '72 Z for a couple of months now, had a lot of fun and got to know what I need to address while putting on some miles. I just changed the plugs, did a compression test, checked the timing and set the points gap.

I am happy with the compression, 150 across the board dry and 160 to 170 wet, the variability was probably due to how much oil I squirted in each cylinder. May be able to get away with just a re-ringng it in the future

The front three spark plugs looked great the back tree were black, I need to adjust the carbs the back must be running rich. Plug gap was way too small, I put in new plugs with correct gap. Similarly the point gap was almost non existent, so I set it to .018 and the car seems much happier, starts up easier and runs smoother.

checking the timing it seems to be around 5 degrees btdc and when revved it runs up over 30, it's very difficult to see the marks I'm going to clean up and paint the marks to get a better idea. (I'll confirm tdc when I set the valves).

Now my question, I had to loosen the fan shroud to get a 27mm socket on the crank nut. What a pain!!! In the end it worked for setting the points, but there must be a better way. How do you guys spin the engine when you set the points gap?

Thanks! Steve

Edited October 12, 2014 by sdyck

[Zed Head]

If it's a manual transmission you can put it in to high gear and move the car by pushing on a tire to turn the engine. That will get you close. Then twist the distributor shaft mechanical advance mechanism to get on the lobe.

[Pat Carr]

[Now my question, I had to loosen the fan shroud to get a 27mm socket on the crank nut. What a pain!!! In the end it worked for setting the points, but there must be a better way. How do you guys spin the engine when you set the points gap?]

To get the distributor on the knuckle, I put it in second gear, release the brake, and just nudge the car back and forth as needed to get it in position. Don't do this on a hill!:classic:

[zKars]

The best solution to the points setting issue is get rid of the points. There are several reluctor based distributors available, from later ZX dizzys that bolt right in to Pertronix aftermarket and even uber fancy fully programmable ones from 123IgnitionUSA. Points are SO last century....

[sdyck]

I did a little of the roll the car thing in gear, feels so inaccurate though. My MG was always so easy to access, also used a bump starter to get it close.

PerTronics in my future. Motorsport auto shows a kit for the '70-'73 at a reasonable price, I assume it works works with the stock distributor?

[Zed Head]

You can build a bump starter with a piece of wire and a single female connector of the same size as the terminal on the starter solenoid. The wire just needs to be long enough to reach from the solenoid to the battery positive post. Two feet is about right.

OR, even more primitive - a screwdriver to bridge the gap between the end of the positive cable and the solenoid terminal.

[Stanley]

I use the key until it lands close to a node for a ballpark setting, then use the dwell meter on the dwell/tachometer or the digital timing light to fine tune it.

IIRC, once I fried a fusible link with the screwdriver method.

Question: the FSM gives a range for the dwell, 35 to 47 degrees or something like that. Should you aim for the smaller gap, since the points will wear down? Or is best performance somewhere else? Last time I set it for the middle of the range, but don't have a reason for it.

Edited October 12, 2014 by Stanley

[siteunseen]

Bump starter, especially for adjusting the valves. $15 at Auto Zone.