Can I manually crank my 1974 914 2.0 engine?
 

I have the engine and drive train on the bench and want to confirm it is not seized up. If I remove the spark plugs, how can I turn it over without using the starter?

carefully use a big screwdriver and turn it through the timing hole paying particular attention to the fan blades as you can break them off, turn from the back of the fan where the blades are attached NOT the front

Thank you ...I'll give it a try later today.

Seen many a fan blades broken this way.

As mentioned they are magnesium and only cast to the back of the fan on one side and not the metal hub.

Be really careful.

yes yes yes and only with the spark plugs out. We have over 100 fans with broken blades on the shelf

Nailed!
 

Nailed!
Turns over easily, no bbroken fan blades.
Next is bench testing. All comments on the best set up and procedures are welcome.
Cheers!

Next time, assuming you have the transmission attached, it shoud be possible to fix one driveshaft flange in place, and turn the engine over using the other flange.

I agree. Just think that using the fan blade is a really lazy way to either line up the timing mark or to turn the motor. You will end up breaking the fan blade(s) and then an unbalance the fan. Just too risky, and then will unleash a **** load of other problems.

To adjust the valves with the motor in it you can do the same thing, except use the wheel to turn the motor once the other wheel is chocked. Makes it real easy.

I have seen mechanics actually put the car in 2nd gear and push it to turn the engine, takes time, and if you are adjusting the valves inefficient. The fan blade trick works well and easily if the spark plugs are out and the car is in neutral and one is very very careful. You can monitor where the rotor is pointing and look at top dead center at the same time and get a perfect adjustment

Yep. I agree, it is a fast easy way to find the mark and break a fan blade by a mechanic making flag time and an unaware or uninformed customer.

As far as adjusting the valves that is not the fastest way to do it.

It's a boxster motor so you know by the firing order which valves are open and which are closed and the timing mark is conveniently in the hole in a 901 right there staring you in the face. Never have to look at the distributor.

I would never advise somebody to crank the motor this way unless you don't care about your fan. IMHO.

Sounds right, and I think that's the way I turned the motor when adjusting valves (on my back under the car on jack stands).