Optics

I have a new engine (rebuilt but sat for the last year and a half) and I just want to make sure that its in good shape before I bolt everything to it. Right now its sitting in the bay with the tranny and starter and plugs and tape over all the water inlets / outlets and over both the intake and exhaust manifold spaces. All sensors etc are in the engine and it has oil in it (oil cooler hooked up w/ lines) but its not wired into the car yet so all sensors are just dangling.

Now my question is can I just wire in the starter and run a compression test on this engine without the manifolds on or will that be dangerous to the engine (how?) or myself (how?). If its safe for me / the engine then will it give an accurate representation of compression?

I spun the engine by hand and listened to it and it sounded good, but I just want to have a bit more piece of mind before all the fuel lines / manifold goes onto the block. It would be alot easier to pull again now then after. Thanks for your input!

classicauto

iTrader: (3)

well, if there's no fuel hooked up, just give'r

The proper compression test should be done at full throttle anyways while cranking, so having no manifolds on there is about as full throttle as it gets

Should give you an idea of whether or not any of the seals have stuck anyways....

Sideways7

iTrader: (7)

Just make sure that there is nothing around that could possibly be sucked into the engine when it is cranked. Other than that, its perfectly fine to do, and I have done it several times.

AllMotorRotor

Its actually better to do the compression that way so you can see the maximum amount of compression the engine can have at around 200rpm on the intake ports it has.

TehMonkay

iTrader: (-1)

Actually, i just helped a friend do this tonight, wasn't even in a car. We jumped it with another car and hooked the solenoid up to a 12v source.

Sucked, it had 75 up front and 100 in back, most likely due to carbon deposits, there were literally chunks of crap stuck in the sleeve for the 6th port.