Starter relay
 

Ladies and gentlemen,

Please help.

The starter motor on my 1977 911 does not appear to have a relay anywhere. Is this correct?

The ignition switch (yellow wire for starter on the back of the ignition switch) goes straight to the starter, through various connectors obviously.

Thank you chaps.

You're correct. No separate relay. The solenoid is the relay.

Sherwood

Thankyou Sherwood.

However, some people put in this: http://www.pelicanparts.com/catalog/images/electrical/hot_start_kit.jpg
to avoid too much juice going through the ignition switch.
This also insures that full power goes to the solenoid/starter and extends the life of the yellow wire.
Any 12V/30A relay will do.

Has anyone measured the current flow through the yellow ign. switch wire?

Sherwood

Ok all you electrical genius's. This is my dilemma.

I replaced the starter switch with a brand new one (not a cheap exercise) and this is what I have now.

I hooked everything up before I reinstalled the switch in the dash so that I could test various things. I turn the key and everything works at the right time - accessories - engine powered - fuel pump etc.

When I turn the switch to hit the starter there is no power coming from the back of the switch to the big yellow wire (starter motor).

This only leaves me with the impression that the switch is faulty (brand new switch doing the same as the one replaced - too coincidental for me). The big yellow wire is the only one that does not become energised (no, not energized - this is Australia) at some point during my turning of the key.

I am driving on Saturday so I will hot-wire the starter tomorrow straight from somewhere in the engine bay to get going. Not ideal but I need to drive (you good gentlemen can understand this).

Thank you chaps.

You can energize the solenoid by using a screwdriver going across from the main connection (Red wires) to spade connection for yellow wire. Make sure that the car is in neutral; there will be a little spark. Ensure good ground connections; check the ground strap from the transmission to body and from negative terminal to body. Clean and lube with dielectric grease.
Consider the relay kit mentioned above after you find the problem.

Where did you measure? That is, when the starter switch is turned to where voltage should be present in the yellow wire, and you found that the yellow wire had no voltage, where were you connecting the test leads on the yellow wire? A pin or needle can tell you whether there is voltage in the yellow wire, one inch from the starter switch. I recently had a terribly bad connection at the 14-pin connector at the engine compartment fuse panel, giving this same symptom.

Another idea is that perhaps the ignition tumblers are worn out. Heavy keychains can wear them so much that they eventually fail to turn far enough to activate the starter switch. The PO of my car had to replace the ignition tumbers, presumably for this reason. Better him than me since that's about a $600 part.

I hate to admit it "Superman" but I wasn't turning the key hard enough. When the ignition switch was hanging down, I didn't turn the key really hard. I thought I had it all the way to the starter point, but I didn't.

The new keys came with a really small head on them. When I start the car now I have to turn so hard that it hurts. My car is now in great shape, and its back on the road for me.

Thankyou everybody.