Engine changed, car won't start, followed the WIKI - stuck

[jimbom30cab]

The car: Aug 1987 prefacelift 325i sport

The Engine: Was originally a SuperETA prefacelift but converted to DME1.3 and originally fitted to a facelift e30

Now I've put it in a pre-facelift (which had DME 1.1)

Good battery, all connections checked and engine is well earthed

Observations:

When the key is turned on the ICV buzzes away and the check light and inspection light come on. No other indications.

The car wont start although the DME and a relay inside behind the glove box do click.

I have jumped the coil (terminal 15 from the battery - nothing)

Tried to start on the diagnosis connector jumping pins 11 and 14 - nothing

But when I put a bulb on pin 11 on the diagnosis connector it was lit and dim - there was 10v there. When we turned the key to start it went v bright.

So I checked the cab (m30 DME 1.3) and there should be zero volts at the pin 11 and 12v only when the engine is cranking

I've taken a couple of pics







I'm Mr Thicky at all this but I think I have got live voltage (but only 10v) at the starter solenoid 2.5 black/yellow when I should have zero.

Why.....god only knows !!

Any help very much appreciated

[Brianmoooore]

You've written 10 volts against the earth terminal of your starter motor on the circuit diagram. If this is the case, there's a problem with the engine to body earth strap (or you haven't fitted it at all!)

[jimbom30cab]

ok, thanks Brian, the strap is fitted and I've checked for continuity, the terminals were also given a good file back to ensure a clean and tight connection.

[Brianmoooore]

Where was the neg. terminal of the meter connected when these readings were taken?

[jimbom30cab]

Hi, I know this is going to seem a bit embarrassing for me but I just thought I would check the earth so I put one of my jump leads onto the earth strap on the solenoid and the other end onto the strut top mount bolts. Turned the key on, all indication came on, went to start and she turned over (I realised the key straight away)

Little bit of smoke from the connection to the strut top mount

Has this proven I have got a insufficient engine earth ?

[Brianmoooore]

You have a faulty earth path, for sure. The 'path' consists of any bolted joints between the starter motor and the engine end of the engine to body earth strap, the strap itself and its connections at each end, and the battery negative lead from the top of the RH suspension turret to the battery negative pole.
Smoke is a good indicator of where the problem is.

[bss325i]

Have you powder coated the engine mount arms?

[jimbom30cab]

You know me too well Barry, yes, the eng arm mounts were power coated.

I actually have fitted another earth strap from the block to the chassis rail connection and it's sorted it's self out now.

Turns over nice.....doesn't start yet but that's tomorrow problem, beer time now.

[jimbom30cab]

Thanks Brian and Barry.

[DanThe]

Ive seen it several times where people have painted engines/mount arms and dont think to remove the paint for the earth straps, your not on your own, and your lucky you havnt burned out the oil level sensor earth wire in the engine loom

[jimbom30cab]

The funny thing was Dan I had removed any paint and filed back (have witness), maybe I've put the earth strap in the wrong place then as mine is fitted to the sump but the oil level sensor. The new one I fitted bolts right onto the block by a round blanking plate (behind the alternator).

I don't really know m20 engines TBH....