Thread: 67 mustang engine compression

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Is there any way for me to check the compression of the engine in my 1967 mustang straight 6 engine if the engine is not in the car?

Originally posted by DennyW
Yes, the same as if it was in the car. Block it up good, make sure nothing that rotataeswill hit the ground as it rotates. Pull all the plugs, prop the throttle open. Do not hook up the coil. Get yourself a charged battery. Take a set of jumper cables. Hook the + cable to the starter big post, and to the plus battery post. Hook the neg to the battery neg post. The other, hook to the engine ground when you want to crank it over. After you put your compression gauge in the plug hole. Does this have a starter mount solenoid? Oh, just looked at the year again. If stock, it will have a fender well solenoid. Do you know how the wires hook there, and at the starter ?

what damage is done if you dont pull all plugs and not open throttle? I checked my '67 Falcon compression by pulling a plug at a time, and I never opened the throttle.

it does hav a starter mount solenoid

Originally posted by DennyW
No damage Matt. It all depends on how accurate you want the check, and at the same cranking rpm's. A no load test will keep rpm's closer because by the time you get to the last depending on battery condition, you may be 75 rpm's slower.
Proping the throttle open is so no fuel is sucked down the intake into the cylinders. Again, depends on how close you want the test, and you want a clear air flow to the cylinders also.

I will have to check it again the way you said. I had 1 and 3 cylenders odd from the rest, they were low but within 10%, 1 was oily and wet, 3 looked great, all the rest were just wet.