Help a newbie '77 123 Starter motor

"Give" you a 1978 450SL, as a gift? Can you introduce me to your friend?

Vlad wrote:

> On Tue, 12 Jul 2005 12:29:44 GMT, "Jeremy Miller"
> <jm4221.DeleteThis@bigpond.net.au> wrote:
>
>
>>Hey guys,
>>
>>
>>I have recently been given a MB for the tidy sum of $0.
>>
>>It's a '77 280E (123 Chassis)
>>
>>Yes I'm stoked. Can't wait to drive it .
>>
>>I've been poking around under the bonnet for a few days now. Boy am I
>>impressed by the degree of engineering on these things!
>>How ahead of there time are they !
>>
>>Ok the car has been sitting untouched for about 9 months.
>>
>>I've replaced the battery.( It was dead ) The starter motor does not want to
>>respond when Turning the ignition key over to start.
>>
>>The motor turns over fine Manually (with a ratchet on the front of the
>>engine).So it's not ceased or anything.I Managed to loosen the starter up a
>>bit
>>by tapping the Body and the solenoid.
>>
>>I now have made a bit of progress and I'm actually hearing a faint Click
>>every now and then.
>>
>>I've cleaned the battery terminals and also the ground from the battery to
>>the body.
>>
>>Is there an earth strap going from the Engine block to the Chassis anywhere?
>>
>>My main questions is how to go about pulling the Starter motor.
>>
>>The lower bolt is hard to access via socket or open wrench and ring
>>spanner.
>>
>>The upper bolt looks to be an allen/Hex key?
>>
>>Do I need any special tools at all.
>>
>>Also I can't access the Connectors on the soleniod.
>>
>>Do I have to remove the rear exhuast manifold and heat shield?
>>
>>Thanks for any help.
>>
>>Jeremy Miller
>>
>
> I am not familiar with your particular model but I am familiar with
> cars in general (Jaguar).
>
> When an old car is parked for a long time, it's not unusual for the
> starter brushes to fail from making a good contact. If you can move
> the position of the brushes by a minute amount you may solve your
> problem
>
> Tapping the Body and the solenoid as you have done sometimes works.
> Try again with a piece of wood.
> A piece of wood was part of the tool box on my wife's Mustang . It was
> used more then a dozen times.
>
> If the car is manual, there are ways of forcing the starter to rotate
> a little, but they are too dangerous for people without experience.
>
> If you can try the following:
> Connect a voltmeter between the heavy wire that goes to the starter,
> from the starting relay and the starter body (not the car's body)
> Try starting the car. If you have voltage (+12) and the starter
> doesn't run the problem is with the starter
> If you don't have voltage, measure between the same heavy wire and the
> chassis ground . Try starting the car. If you have voltage the problem
> is a bad ground. Confirm by connecting between the starter ground and
> the car chassis. If there is voltage you have a bad ground.
>
> A friend of mine wants to give me a 1978 450SL.
>
> Vlad
 >> Stay informed about: Help a newbie '77 123 Starter motor 

Out of caution I'd suggest you first convince yourself that the starter
is, in fact, the problem. It may very well be given the car's age, but
you'd be crestfallen if you replaced the starter only to find no change.

Have you confirmed 12V at the starter when the key is turned to START?

If not, then the other possibilities are: ignition switch, neutral start
safety switch, etc.

I'd suspect this car wasn't driven for nine months because nobody could
solve the problem.

There's a lot of knowledge in this group, most of it good, so come back
with your questions.
 >> Stay informed about: Help a newbie '77 123 Starter motor 

There is a ground strap that runs above the battery tray on the
firewall to the transmission linkage/dipstick area.Also the ground wire
from battery to the fender is suspectable to corrosion.

To remove starter,go under the W123 and use 2 long 3/8 extensions with
a 17mm socket and another ratchet or box wrench and remove bottom bolt
and then the top.After the starter comes down,you can then remove the
wires.Pay close attention when you reinstall the starter and avoid the
wiring touching the shield or manifold.

One last thing to consider is checking the connections for corrosion on
the little junction that is located on the frame near the alternator
and AC.
 >> Stay informed about: Help a newbie '77 123 Starter motor 

Oh yeah I forgot to add that the hex is a 8mm if I am not mistaking but
not 100% sure.If you do not have a socket/hex,you can make one by using
a cutoff tool(dremel) and cut off the right angle off of allen wrench
and stick the straight piece in a 3/8" deep well socket.
 >> Stay informed about: Help a newbie '77 123 Starter motor 

Jeremy Miller wrote:
> Hey guys,
>
>
> I have recently been given a MB for the tidy sum of $0.
>
> It's a '77 280E (123 Chassis)
>
> Yes I'm stoked. Can't wait to drive it .
>
> I've been poking around under the bonnet for a few days now. Boy am I
> impressed by the degree of engineering on these things!
> How ahead of there time are they !
>
> Ok the car has been sitting untouched for about 9 months.
>
> I've replaced the battery.( It was dead ) The starter motor does not want to
> respond when Turning the ignition key over to start.
>
> The motor turns over fine Manually (with a ratchet on the front of the
> engine).So it's not ceased or anything.I Managed to loosen the starter up a
> bit
> by tapping the Body and the solenoid.
>
> I now have made a bit of progress and I'm actually hearing a faint Click
> every now and then.
>
> I've cleaned the battery terminals and also the ground from the battery to
> the body.
>
> Is there an earth strap going from the Engine block to the Chassis anywhere?
>
> My main questions is how to go about pulling the Starter motor.
>
> The lower bolt is hard to access via socket or open wrench and ring
> spanner.
>
> The upper bolt looks to be an allen/Hex key?
>
> Do I need any special tools at all.
>
> Also I can't access the Connectors on the soleniod.
>
> Do I have to remove the rear exhuast manifold and heat shield?

Almost sure the problem will be the starter relay sitting on top of the
starter. Give it a blow with a hammer while someone else holds the
starter key. Demount the starter and grease the ralay bolt. IIRC you can
pull out the starter from downside with some twists around the exhaust
manifold. At least that was the case with a /8 300D. My 280E never had
any problem with starter.

--

Roland Franzius
 >> Stay informed about: Help a newbie '77 123 Starter motor 

The fuel pump safety switch is located in the airflow sensor.If you
look at the top of this sensor,you will see an electrical
connection(blue)
and to change,sadly you have to disassemble but is fairly easy.The 10mm
bolts that go around are all that holds the two halves together.The
hard part is removing the fuel lines from the fuel distributor.
To prevent kinking them,loosen at the injector also!
If time and money allow,replace the injector O-rings and sleeves.
 >> Stay informed about: Help a newbie '77 123 Starter motor 

Forgot to add:possible causes

Jammed or sticking airflow sensor

Auxiliary air valve sticking

Cols start injector not opening

Defective thermo-time switch

Sticking control plunger

Restricted injectors

Do a volume and pressure test after you get the fuel pump to behave! 75
to 84 psi on the fuel pressure.

Fuel pump relay specs:
Place an 8 amp fused jumper between fuel pump relay(on top of front
fender under black cover,and is the one closest to the engine and
firewall)sockets terminals 30/51 and 87.
 >> Stay informed about: Help a newbie '77 123 Starter motor 

Thanks for all the help!

Ok I've had the Starter Tested and the Brushes were stuffed!

The Soleniod (Starter relay?) tested fine.

I reinstalled the starter and Finally have her cranking.

Cleaned all the grounds.Checked for corrosion on the power distribution
block, cables and wiring

The Fuel pump was also dead! So I Popped a new one of them in too.

I can now hear the fuel pump pressursing the system when turning the key on.

She fired straight away and idled perfectly for about 40 seconds!!!

Then died. I tried starting it again straight away. But she wouldn't fire!

And I couldn't hear the fuel pump running???

Had a bit of a read through the online MB manuals.

And found that the fuel pump relay is located behind the Glovebox.

I disconnected that and tried to start it.
The fuel pump worked but she didn't want to crank!!

Reconnected it and the same thing again. Fuel pump on but no crank.


There is 12V at the starter Soleniod (main terminal).

I'm getting a faint click from the small Square relays mounted next to the
fuse box

Is one of these another relay for the starting system?

Where is the safety switch located?

Thanks for all the help again( I'm so close).

My plans for the car are new Black paint a nice set of Polished wheels 17 or
18 inch.



"Jeremy Miller" <jm4221 RemoveThis @bigpond.net.au> wrote in message
news:YIOAe.38560$oJ.12138@news-server.bigpond.net.au...
> Hey guys,
>
>
> I have recently been given a MB for the tidy sum of $0.
>
> It's a '77 280E (123 Chassis)
>
> Yes I'm stoked. Can't wait to drive it .
>
> I've been poking around under the bonnet for a few days now. Boy am I
> impressed by the degree of engineering on these things!
> How ahead of there time are they !
>
> Ok the car has been sitting untouched for about 9 months.
>
> I've replaced the battery.( It was dead ) The starter motor does not want
> to respond when Turning the ignition key over to start.
>
> The motor turns over fine Manually (with a ratchet on the front of the
> engine).So it's not ceased or anything.I Managed to loosen the starter up
> a bit
> by tapping the Body and the solenoid.
>
> I now have made a bit of progress and I'm actually hearing a faint Click
> every now and then.
>
> I've cleaned the battery terminals and also the ground from the battery to
> the body.
>
> Is there an earth strap going from the Engine block to the Chassis
> anywhere?
>
> My main questions is how to go about pulling the Starter motor.
>
> The lower bolt is hard to access via socket or open wrench and ring
> spanner.
>
> The upper bolt looks to be an allen/Hex key?
>
> Do I need any special tools at all.
>
> Also I can't access the Connectors on the soleniod.
>
> Do I have to remove the rear exhuast manifold and heat shield?
>
> Thanks for any help.
>
> Jeremy Miller
>
 >> Stay informed about: Help a newbie '77 123 Starter motor 

Thankyou for the help Captain.

At the moment the fuel pump is working.
But she doesn't want to Crank.

I'm just getting a faint click?

"CaptainW116" <benznut450.RemoveThis@yahoo.com> wrote in message
news:1122467583.365878.6290@g43g2000cwa.googlegroups.com...
> Forgot to add:possible causes
>
> Jammed or sticking airflow sensor
>
> Auxiliary air valve sticking
>
> Cols start injector not opening
>
> Defective thermo-time switch
>
> Sticking control plunger
>
> Restricted injectors
>
> Do a volume and pressure test after you get the fuel pump to behave! 75
> to 84 psi on the fuel pressure.
>
> Fuel pump relay specs:
> Place an 8 amp fused jumper between fuel pump relay(on top of front
> fender under black cover,and is the one closest to the engine and
> firewall)sockets terminals 30/51 and 87.
>
 >> Stay informed about: Help a newbie '77 123 Starter motor 

"Jeremy Miller" <jm4221 RemoveThis @bigpond.net.au> wrote in message
news:HdKFe.64301$oJ.13013@news-server.bigpond.net.au...
> Thanks for all the help!
>
> Ok I've had the Starter Tested and the Brushes were stuffed!
>
> The Soleniod (Starter relay?) tested fine.
>
> I reinstalled the starter and Finally have her cranking.
>
> Cleaned all the grounds.Checked for corrosion on the power distribution
> block, cables and wiring
>
> The Fuel pump was also dead! So I Popped a new one of them in too.
>
> I can now hear the fuel pump pressursing the system when turning the key
> on.
>
> She fired straight away and idled perfectly for about 40 seconds!!!
>
> Then died. I tried starting it again straight away. But she wouldn't fire!
>
> And I couldn't hear the fuel pump running???
>
> Had a bit of a read through the online MB manuals.
>
> And found that the fuel pump relay is located behind the Glovebox.
>
> I disconnected that and tried to start it.
> The fuel pump worked but she didn't want to crank!!
>
> Reconnected it and the same thing again. Fuel pump on but no crank.
>
>
> There is 12V at the starter Soleniod (main terminal).
>
> I'm getting a faint click from the small Square relays mounted next to the
> fuse box
>
> Is one of these another relay for the starting system?
>
> Where is the safety switch located?
>
> Thanks for all the help again( I'm so close).
>
> My plans for the car are new Black paint a nice set of Polished wheels 17
> or 18 inch.
>
>
>
> "Jeremy Miller" <jm4221 RemoveThis @bigpond.net.au> wrote in message
> news:YIOAe.38560$oJ.12138@news-server.bigpond.net.au...
>> Hey guys,
>>
>>
>> I have recently been given a MB for the tidy sum of $0.
>>
>> It's a '77 280E (123 Chassis)
>>
>> Yes I'm stoked. Can't wait to drive it .
>>
>> I've been poking around under the bonnet for a few days now. Boy am I
>> impressed by the degree of engineering on these things!
>> How ahead of there time are they !
>>
>> Ok the car has been sitting untouched for about 9 months.
>>
>> I've replaced the battery.( It was dead ) The starter motor does not want
>> to respond when Turning the ignition key over to start.
>>
>> The motor turns over fine Manually (with a ratchet on the front of the
>> engine).So it's not ceased or anything.I Managed to loosen the starter up
>> a bit
>> by tapping the Body and the solenoid.
>>
>> I now have made a bit of progress and I'm actually hearing a faint Click
>> every now and then.
>>
>> I've cleaned the battery terminals and also the ground from the battery
>> to the body.
>>
>> Is there an earth strap going from the Engine block to the Chassis
>> anywhere?
>>
>> My main questions is how to go about pulling the Starter motor.
>>
>> The lower bolt is hard to access via socket or open wrench and ring
>> spanner.
>>
>> The upper bolt looks to be an allen/Hex key?
>>
>> Do I need any special tools at all.
>>
>> Also I can't access the Connectors on the soleniod.
>>
>> Do I have to remove the rear exhuast manifold and heat shield?
>>
>> Thanks for any help.
>>
>> Jeremy Miller
>>
>
>
 >> Stay informed about: Help a newbie '77 123 Starter motor