I've searched but can't find exactly what I'm looking for.
I have a motor (still in the car) that I'm trying to test compression on before I remove it. I have most of the FI/engine wiring harness disconnected so I'm wondering if I can wire up leads from a battery to the starter/solenoid so I can crank the engine over? Is there an easy way to do this?
Full Version: Wiring / jumping the starter
You need to hook up the battery, ground and positive.
Large positive goes to large terminal on the starter.
Ground could go on the lower bolt of the starter, or just make sure the normal tranny strap is in place.
Make up a 30 am starter push button switch and connect on end to the positive terminal of the battery, and the other end is a femal spade bit on the starter solenoid.
Press button...off you go.
For rapid action, take a screw driver and touch the larger terminal on the starter to the male spade bit on the starter...same results.
If
Ed was there, he would show you a quarter fits between the spade terminal and the larger on on the starter, same results.
Now, your compression test will not really show you much with the engine cold, in fact your results will be worse, so until the rings best up and expand....your compression will suck.
Large positive goes to large terminal on the starter.
Ground could go on the lower bolt of the starter, or just make sure the normal tranny strap is in place.
Make up a 30 am starter push button switch and connect on end to the positive terminal of the battery, and the other end is a femal spade bit on the starter solenoid.
Press button...off you go.
For rapid action, take a screw driver and touch the larger terminal on the starter to the male spade bit on the starter...same results.
If
Ed was there, he would show you a quarter fits between the spade terminal and the larger on on the starter, same results.
Now, your compression test will not really show you much with the engine cold, in fact your results will be worse, so until the rings best up and expand....your compression will suck.
QUOTE(r_towle @ Jun 8 2015, 09:05 PM) 
You need to hook up the battery, ground and positive.
Large positive goes to large terminal on the starter.
Ground could go on the lower bolt of the starter, or just make sure the normal tranny strap is in place.
Make up a 30 am starter push button switch and connect on end to the positive terminal of the battery, and the other end is a femal spade bit on the starter solenoid.
Press button...off you go.
For rapid action, take a screw driver and touch the larger terminal on the starter to the male spade bit on the starter...same results.
If
Ed was there, he would show you a quarter fits between the spade terminal and the larger on on the starter, same results.
Now, your compression test will not really show you much with the engine cold, in fact your results will be worse, so until the rings best up and expand....your compression will suck.
So Will the screwdriver trick work if I have the starter wired straight to a battery?
Just to clarify, I've got the engine still in the car, since my 914,s battery is dead, I'm using a spare battery from some other car to try to make long jumper wires from the battery to the starter leads. The spare battery does not fit in the 914, and I can't hook it up to the 914s battery connections.
And so a cold engine compression check is pointless?
And so a cold engine compression check is pointless?
It's not pointless, but the readings will be less than those of a hot engine with the piston rings expanded etc. So don't expect to match the hot range listed in the haynes manual. You will probably be able to verify all cylinders are reading within range of each other if no problems exist.
Make sure your spark plugs are removed and the throttle body is open.
And your transmission is in neutral!
You can buy a cheap universal starter push button switch at your flaps.
Make sure your spark plugs are removed and the throttle body is open.
And your transmission is in neutral!
You can buy a cheap universal starter push button switch at your flaps.
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