E30 won't crank

[bobolsn]

I just replaced the engine on my E30-1987 (2.7L). just prior to the transplant, I drove the car into the gagage and unhooked the battery. I finely got the engine in, hooked everything up,charged battery and it will not start. The fuel pump is whuring and all the lights are on, but the started does not make a sound. The following is what I have tried/determined.
- the 2 cables are attached to the + post of the starter and the ignition plug is connected to the solenoid.
- I am getting about 11-12 volts to the started via the cable.
- I tried to bridge the starter by putting a 12V signal to the ignition wire (nothing happened).
- my wife turned the key and I did not get a 12V (or any voltage for that matter) signal from the ignition wire to ground.
- I checked for continuity across the engine ground strap.

As you know it is a PITA to get the starter out to bench test. Also, if I am not getting a signal from the ignition to activate the solenoid it may not be the starter or do I have 2 (or more) problems. I was very careful to hook up everything before hooking up the battery, so I don't think I shorted anything.

Any suggestions before removing the starter? Are there fuseable links? Is there a relay that could cause this? Are the diagnostic steps I performed logical?

Any thoughts will be greatly appreciated. I will post the solution.

TIA

Bob

[coolbear1]

Bob, there are fuseable links, relays, and the like, but if you jump to the starter solenoid, and it doesn't at least scare you I would suspect the starter.

Is it the starter that was on the bad engine, or did you buy a used engine with a starter attached?

I have had several e30s, and, I may be wrong but If I remember correctly the the starter is similar to the starter on a e36, in that it is a Bosch, with the solenoid (main starter relay) attached to the starter.

If so the soleinoid can be energized as you discribed if voltage is present at terminal 30 (the large wire).
Terminal 50 (the smaller wire) should have voltage only when the ignition is turned. Assuming the car is in park, if automatic, or clutch depressed if 5 speed.

If terminal 30 has sufficent voltage, and you energize terminal 30(with 12 volts), from any source, something should happen, at least a spark, regardless of any other condition, malfunction or what ever.

[bobolsn]

Thanks for the reply.

Yes it is the starter that was in the original engine and it worked. It is a Bosch starter and I am getting power to terminal 30. Nothing when I engergize terminal 50 smaller wire.

The other thing is I did not get a 12V (or any voltage for that matter) signal from the ignition wire to ground when the key was turned and the clutch depressed.

Why did 2 things go wrong (the ignition and the starter)? The starter got the car into the garage and there were no prior problems with the starter.

Bob

[JhwShark]

Bob,

You may have a bad ig switch..but it was working prior to the work. You did try to apply 12v bridge to the starter and nothing. How about a few whacks on the solenoid with a rubber mallet (to loosen/unfreeze solenoid) and/or put car in gear (non-AT) and rock it (to loosen any binding on the flywheel).

trying to help,
Jon

[bobolsn]

Thanks for the help.

I believe I figured part of it out. We have an after market alarm installed that has a starter disable option. After referencing the wonderful wiring diagram that roadfly.com made available, I determined that the ignition switch was sending the 12v signal, but it was being intercepted by the alarm system.

So, now the starter. I got a little clicking when I shorted the terminals. Jon, I believe I will try the rocking and whacking. Then I will have the battery tested for cranking amps, cause it is providing about 12v to terminal 30. Then if that doesn't work, I will remove the starter for a bench test.

Again thanks for the quick response.

Bob