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-   -   73 450 SL Distributor points type (http://www.peachparts.com/shopforum/tech-help/368437-73-450-sl-distributor-points-type.html)

Hicks82 05-18-2015 08:35 PM

73 450 SL Distributor points type
 
The local parts house is telling me that if my distributor has clips holding it on. That the condenser is not needed. I am getting fire every where but the plugs. 1973 450 SL . Help!!!!

Frank Reiner 05-18-2015 09:10 PM

1) What problem(s) caught your attention?
2) What does "fire everywhere" mean?

Hicks82 05-18-2015 10:19 PM

Power to distributor , but not to plugs. There is a condenser but the wire has been cut. Power to the points.

Frank Reiner 05-19-2015 11:43 AM

Check coil for continuity: Primary ~ .4 ohm, Secondary 8-11K ohms
With the points open, what voltage is observed at the point arm?
Does the switchgear have a ribbed top or a smooth top?
With key on, what voltage at the coil positive (+) terminal?

Hicks82 05-19-2015 09:04 PM

Voltage at point arm 8.0, coil continuity yes, voltage at coil with key on 2.9. Where is the switchgear located?

Frank Reiner 05-19-2015 11:42 PM

Quote:

Originally Posted by Hicks82 (Post 3477591)
Voltage at point arm 8.0, coil continuity yes, voltage at coil with key on 2.9. Where is the switchgear located?

The switchgear, which is an ignition amplifier, is typically located on the left inner wheel well, fairly close to the coil. It is about 4.5-5 in. square x 1.5 in. deep. Two plugs, a green coax from the distributor, and a four-pin for power leads. The points in the distributor serve only to provide a trigger signal to the switchgear, and as a consequence carry only a very small current. The capacitor was present only for purposes of RFI suppression.

A point gap of about .020" should work OK; just be sure that the points do open and close.

Hicks82 05-20-2015 08:08 PM

I see no box with that description. However there is a silver box mounted in front of the left wheel with four leads that go to two resisters. I am getting power in and out of the resisters. One goes to the points and one goes to the coil.

Frank Reiner 05-20-2015 09:48 PM

Quote:

Originally Posted by Hicks82 (Post 3478062)
I see no box with that description. However there is a silver box mounted in front of the left wheel with four leads that go to two resisters. I am getting power in and out of the resisters. One goes to the points and one goes to the coil.

You have discovered the switchgear.
A coax lead, usually green, should connect the points to the switchgear. There should not be any other lead between the switchgear and/or resistors, and the distributor/points.

The resistors are in series. The furthest downstream connection (through both resistors) goes to the coil positive (+).

Of the leads in the four-pin plug on the switchgear, one is a ground, one goes to coil negative (-), one is a signal out for tach and analysis use, and one goes to the junction between the two resistors.

The single lead plug, of course, is from the points.

Hicks82 05-26-2015 08:35 PM

Distributor points type
 
Ok, I have 8.1 volts to the points arm with the points open. And, 3.2 volts out of coil. 7.9 volts into the resistor. Still no spark?

Frank Reiner 05-26-2015 08:43 PM

Hicks82:

Can you provide some pictures of the components that you are dealing with?
Can you sketch a wiring diagram of the connections to the switchgear?

Hicks82 05-26-2015 11:14 PM

2 Attachment(s)
Attachment 129702

Attachment 129703

Frank Reiner 05-27-2015 09:34 AM

Hicks:

In your post #7 you said that there was "a silver box mounted in front of the left wheel". It is not in the pictures. Where is it, and how is it connected?

There appears to be a green wire connected to the distributor/points. Where is the other end connected? Where is the wire from the coil negative (-) connected?

Hicks82 05-28-2015 09:03 PM

wiring diagram
 
1 Attachment(s)
The silver box/switchgear is mounted under the inner finder, in front of the left wheel. It's a Bosch 0 227 0510 17. Key to the new picture I have posted.

1- Switchgear.
2-Black wire from Switchgear to 0.6/silver band resistor.
3-Green and black wire out of 0.6/silver band resistor to (+) positive terminal on coil.
4- Red from switchgear to the 0.4/blue band resistor.
5-Brown from switchgear to the top of the T.B. terminal to Ground.
6- Green from switchgear to the bottom of the T.B. terminal to distributer/points.
7-Coil (-) negative terminal to Ground.
8- Black & Red wire from car to 0.4/blue dand resistor.

Hicks82 05-28-2015 09:06 PM

wiring diagram
 
1 Attachment(s)
Same pic.

Frank Reiner 05-29-2015 03:04 PM

Hicks82:

I have requested a posting of the original switchgear wiring diagram from "Graham". Eventually it should be up.

In the event that "Graham" is not able to provide one, does someone else have a diagram for the earliest ignition switchgear, it's the one with a single, 4-wire, oval connection.


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