compression test

If you are working alone as I always am, you'll need a method to hold the trottle open while you are cranking. If you don't have the stock solenoid with the button on the bottom, maybe you use a simple remote start switch between the small terminal and a ground. But back to the wide open throttle, I use a wooden prop or a weight to depress the gas pedal. When test is complete, don't forget to take the brick off the accelerator. And don't ask why I mention this. Then report your numbers as I'm always interested in this subject. Also your distance above sea level. You in Denver or Death Valley? Makes a big difference.
 
remove all plugs, open throttle all the way. attach a vacuum gauge to intake and make sure there is NO gas going to carb



What is the reason for the vacuum gauge? I have never used one. I would have thought, seeing that the throttle is wide open, the vacuum gauge would read zero.
 
i simply removed each sparkplug in turn and screwed in my compression gauge, then used my cheap remote starter button to crank the engine over while the ignition switch remained in the "off" position. nothing fancy... i got about 110-120 on all the cylinders.
 
The engine cranks faster with all the plugs out, but maybe not an issue?

only if one was looking to reach some particular amount of compression that they thought necessary. i know what puts me in the ballpark and am much more concerned about uniformity than anything else. and for that one only needs to perform the same test on each cylinder.

and my generator will recharge the battery if necessary, when i drive the car. or i suppose i could just throw my charger on it...
 
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