Alfa Romeo Forum banner

1 - 20 of 39 Posts

·
Registered
Joined
·
4,239 Posts
Discussion Starter #1
Help guys.

Engine all ok and ready to go. Plugs out and turns smoothly but firmly with all new shells.

Starter motor does nothing.

It reads 4.5 volts when I turn the key!!!#
Resistance between + and - shows around 2.5 - 3 ohms.

Shouldn't the motor read 12-15 volts when started?

Battery charged at 14.7 volts.


Is the motor burnt out due to the low resistance?

Urgent assistance needed as we need the car to leave holiday home next week.

3 black cables attached to the bolt and one white plastic connetion on the top copper thing.
Is it wired badly?

:cry::cry::cry::cry:
 

·
Registered
Joined
·
4,239 Posts
Discussion Starter #2
I measured the braided wire (solenoid) and only .8 volts!!

Shagged solenoid?
What now?
 

·
Registered
Joined
·
1,458 Posts
The starter motor should have low resistance, less than 0.2 Ohms.
Any resistance in the power supply route seriously affect the operation
of the starter motor (e.g. bad earth @ the engine - as woody mentioned and/or
bad connection at the battery).

Do you hear the starter solenoid operate when you turn the key?
 

·
Registered
Joined
·
4,239 Posts
Discussion Starter #6
I have 13 volts at the solenoid from the battery. That's ok.

But when I start, less than 1 volt on the braided wire from the solenoid to the starter motor.
NO NOIS no clunk. nothing.

Suspeting a burnt solenoid.


Has the engine got a good earth??
Out of the 3 large black wires is one of these the ground? I don't think so.

It span for a few times yesterday without the sparks.

I installed the sparks and then a click then nothing with a slight burning smell.
Volts still arrived at the solenoid though.

Guessing a burnt solenoid.
 

·
Registered
Joined
·
4,239 Posts
Discussion Starter #7 (Edited)
ok some photos

How do I measure the start motor resistance? I was measuring the wrong connecctions. Between the 2 large exterior srews?

ALSO where is the earth connection for the starter motor?
 

·
Registered
Joined
·
1,458 Posts
There should be a centralised earth bolted to the engine block
adjacent to the starter motor, and there should be a thick black
wire bolted to this, which is coming form the battery - terminal
directly.
 

·
Registered
Joined
·
1,458 Posts
...and there should be a thick red wire which is coming from the battery + terminal
directly, this should be connected to the upper connection of the solenoid.
There are two thinner red wires coming from the alternator, these should be connected
to the upper connection of the solenoid as well.
The solenoid lower connection is for the braided wire.
 

·
Registered
Joined
·
4,239 Posts
Discussion Starter #10
There should be a centralised earth bolted to the engine block
adjacent to the starter motor, and there should be a thick black
wire bolted to this, which is coming form the battery - terminal
directly.
yes this is attached well.

...and there should be a thick red wire which is coming from the battery + terminal
directly, this should be connected to the upper connection of the solenoid.
There are two thinner red wires coming from the alternator, these should be connected
to the upper connection of the solenoid as well.
The solenoid lower connection is for the braided wire.
No red wires - just the 3 thick black wires as shown in the second pic.

There are two thinner red wires coming from the alternator, these should be connected
to the upper connection of the solenoid as well.
just one white connetor as shown in pic 1 attacched to the top of the solenoid.
Nothign coming from the alternater unless this is the one.
Should there be 2? There is another copper connection below, should the non apparent cable go to this one?
 

·
Registered
Joined
·
1,458 Posts
Can you trace down the thickest black wire with your DMM?
That should be connected directly to the battery + terminal,
you should measure shortcircuit between thick terminal and
the batt + terminals.

An there should be shortcircuit between the thinner wires
and 2 of the alternator connector (with three terminals: two thicker
and one thin green wire) pins.

If so, these three should be fixed together under the upper big (13mm)
nut of the solenoid.
 

·
Registered
Joined
·
4,239 Posts
Discussion Starter #12
I will test the 3 thick wires now.

Also the small wire with plastic connector is the same as the one on the oil pressure warning sensor. One is grey and the other black.
But I'm pretty sure these are the right way around.
 

·
Registered
Joined
·
1,458 Posts
The "skinny" black one (with the plastic cover) should energize the solenoid
when the key is turned into "start" position.

This can be cheked by measuring the voltage between the skinny black wire's terminal
(disconnected from the starter motor) and ground while the key in start positon.
(the battery must be connected)

The grey wire might be connected to the overheating indicator
 

·
Registered
Joined
·
4,239 Posts
Discussion Starter #14
large thick wire from battery measures 13 volts.

The other 2 show nothing - as you said no?

So if this is all ok then i have a burnt solenoid?
 

·
Registered
Joined
·
4,239 Posts
Discussion Starter #15
The "skinny" black one (with the plastic cover) should energize the solenoid
when the key is turned into "start" position.
this wire shows almost 13 volts once the key is turned.

As mentioned the braided wire shows 0.8 volts once key is turned.:eek:
solenoid not powering the motor I guess.
 

·
Registered
Joined
·
1,458 Posts
The other two black should be the charging from the alternator.
There's no voltage present on these until the alternator is standing still,
that's why i suggested to check the resistance towards the alternator,
just to make sure the function of these wires. (if they remain disconnected
while the engine is fired up that may kills the voltage regulator of the alternator)

If the solenoid doesn't "clunks" that might indicate burnt coil inside, but it's
not too common. The high current contacts inside the solenoid are became
defective more often, but in this case the "clunk" noise is present, only the
starter won't spin up.

So... now the thick black wire (with 13 Volt) is fixed under to the upper nut of the
solenoid, the braided one bolted under the lower nut and the "skinny" black wire
is connected as well, and still nothing?
 
K

·
Guest
Joined
·
0 Posts
ok some photos

How do I measure the start motor resistance? I was measuring the wrong connecctions. Between the 2 large exterior srews?

ALSO where is the earth connection for the starter motor?
energise the solenoid, power to the little wire. then get a ruddy great screwdriver (something metallic and thick) and jam it between the 2 13mm sized nuts, be positive with it, no namby pamby flicks at it. will spark a bit but will also bypass the solenoid. if it turns over ok then your starter solenoid is furbered.
if not much happens then you've a wiring problem

:thumbs:

bit heath robinson but then he taght me well :lol:










and if it catches fire then i'm far enough away from you for it to be no problem, to me :cheese:
 

·
Registered
Joined
·
4,239 Posts
Discussion Starter #18
cheers guys.

jammed a screwdriver in there and nothing. few sparks yes but nothing.

first time I touched the carb linkage bar and it fried the throttle cable!!!!! No fuses blown though.

Second time around no action SO it's shagged in other words?
 

·
Registered
Joined
·
4,239 Posts
Discussion Starter #19
cheers guys.

jammed a screwdriver in there and nothing. few sparks yes but nothing.

first time I touched the carb linkage bar and it fried the throttle cable!!!!! No fuses blown though.

Second time around no action SO it's shagged in other words?
 
K

·
Guest
Joined
·
0 Posts
sounds like the starter itself is beyond help, if you have a good 12V+ at the big lead.


and you now need a new choke cable.. :lol:
 
1 - 20 of 39 Posts
Top