compression test on new motor

[Jlittlej]

Is it possible to do a compression test on a motor that is on a stand?

 

[Quasimondo]

Not unless you you have a complete test rig set up, or at the very least the transmission and starter bolted in and a 12-volt source to crank the starter. What you can do instead is a leakdown test since it doesn't require cranking the motor at all, except for turning the crank by hand to get each piston to TDC to test it.

 

[tsunari]

out of curiosity, why would you want to do a compression test on a new motor? The #'s wont really mean much until the motor has been properly broken in and the rings are seated . . .

 

[Jlittlej]

the motor is only new to me it is a used motor

 

[tsunari]

the motor is only new to me it is a used motor

Oh, ok. . . then yeah- what Mondo said . . . except I dont think you'd actually need the tranny on there if you can find a way to secure the starter + starter plate on. Even then I would be interested to see the setup . . .

Otherwise- do a leak-down test
Check the VFAQ for how to make the tool you need for it