Hey guys, picked up a motor as a project and I'm in the process of a teardown to assess the bottom end and replace the bearings and all gaskets and what not and run a healthier cam in it. My question is:

Have any of you hooked up a starter to your motor while it was on an engine stand and actually turned it over to peform a compression test? Can I do that by just bolting up my flywheel and starter and a car battery. It's on an a/c delco stand that has a decent center of gravity but is still tipable with a good push. I'm wondering if the torque of the starter turning the flywheel is going to violently tip the motor or if I secure/hold it I can turn it over on the stand. Hopefully someone has some personal experience here.

Josh

 

First, if you think that anything short of a #7 on the Richter (earthquake) Scale, might tip the stand, you might be well served to consider something more stable.

Second, for a leakdown test, it is possible if not preferable, to turn the motor to the correct position for testing each cylinder by putting a long-handled breaker bar on the damper bolt at the front of the crankshaft. Be advised that correct positioning of the crankshaft is essential in performing a leakdown. If the piston is not exactly at the top or bottom of the cylinder, the introduction of 100+ pounds of compressed air into the cylinder can cause the rotating assembly to move suddenly and a breaker bar attached to the crankshaft can snap around with enough force to damage anything it hits (like your arm, your 'nads, or your kneecap).

Third, if you remove all the spark plugs there will be less resistance to the torque of the starter motor or breaker bar method of turning the motor.

Finally, it is possible to install the flexplate/flywheel, starter, and battery and click the motor over as needed, IF the stand is steady enough. It's impossible to tell how stable your set-up really is. If you have doubts about it, either start by using a breaker bar to test the stability or take steps to come up with a better stand.

Good luck,

c

 

Thanks for the tips...I'm thinking about stabilizing it on the sides with some bar running down to the floor. I just need to bump it over to test compression on it before I toss it in the car and have to pull the heads while its in the engine bay.

 

hook a cherry picker to the top

 

Lol. That is actually a great idea. I will do that and catch it if it tips.