68 911 electric...please help!!!

mxracer21cba · 02-25-2005, 04:54 PM

Im rounding thrid base on the completion of my first porsche restoration. All has gone well, however, i am having a lot of trouble on the electric side of the job. (the electric on the left of the engine by the fuel pump, coil, etc) Call me a young and dumb 17 year old because i didnt take very good notes on the electric and kind of just dove in. O well i guess you got to learn some how. Anyways, will anyone with a 68 911 or any knowledge of the electric on one please help the rookie out? O yeah there was also one thing i didnt recognize "mark 10" that sits on the engine fire wall, for what i was told it is an aftermarket product to throw more powerful spark to the plugs???? Thanks a lot for your help

chris

Early_S_Man · 06:04 PM

Chris,

Welcome to the land of the Pelicanheads ...

Don't worry, you aren't the first not to take notes ... around here!

How are your schematic reading skills? Here is a link to a factory color schematic for your car ... laid out in what I call the 'topology' or geographic-layout format [top of the diagram is front of car]:

http://members.rennlist.org/911pcars/L59.pdf

The Delta Electronics Mark 10 or 10B was an aftermarket Capacitor Discharge Ignition unit sold in the late '60s and early '70s ... which I used on a Datsun 620 truck for almost 18 years without problems! It is a bit large for the electrical panel of a 911 ... but it was designed to be adapted to almost any production 12 Volt battery-coil ignition on the planet! It used a pair of rather funny-looking adapter boards that were mounted to the coil low Voltage terminals. They were somewhat fragile, and may not still be in one piece! No matter, as the color code of the four wires is the only important detail for reconnecting everything and getting the system running again!

I will post some installation notes/troubleshooting/theory of operation, and other details a bit later ...

Early_S_Man · 02-25-2005, 08:21 PM

Chris,

Here are some scans with theory of operation, installation, and troubleshooting of the Delta Mark 10B system ...

If Thyristor (SCR) operation is a new subject ... here are some resources worth downloading and reading. Adobe Acrobat or Reader will be needed to open the files.

http://www.teccor.com/data/en/Product_Catalogs/ThyristorCatalog1.pdf

http://www.irf.com/product-info/thyristor/manual/scr_manual.pdf

http://www.st.com/stonline/books/pdf/docs/4347.pdf

http://www.st.com/stonline/books/pdf/docs/5201.pdf

Grady Clay · 02-25-2005, 08:26 PM

Chris,

Welcome. Post some photos of your ’68.

What is it exactly that you need?

I’ll get some photos of the ‘68 electrics area in the morning.

Again, welcome to The Forum.

Best,
Grady

mxracer21cba · 02-26-2005, 06:22 AM

hey, thanks a lot for all the great info Warren, ill put it to work when i get home this evening from workin. Grady, ill put up some photos this evening.
thanks a lot guys

mxracer21cba · 02-26-2005, 08:12 PM

Well, i did get a good bit of the electric figured out, however, i didnt have my digital camera today to take pics of what i couldnt understand. I will just try to explain the connections i could not figure out.

1.) The wires that come out of the alternator are all in one casing. Then the the wires split into two sections. The one section is a plug that plugs into the bottom of (what i think is the voltage regulator). The other side goes on at about a ten gauge sized ring terminal (red/white). That same wire (after the ring terminal) goes on and ends in a femal spade connector. Where does the ring terminal and following female spade connector plug in to?

2.) Where does the fuel pump electric plug into?

I know this is kind of confusing without any pictures but i really appreciate the help... if you can understand what im saying that would be great but if not i can get my digital camera tomorrow evening so you can see it with you own eyes.

thanks again
chris

304065 · 02-27-2005, 05:40 AM

Fear not, Chris. Between Warren and Grady you have assembled the most knowledgable team of early car electric gurus imaginable.

Does your harness look like the one owned by Mr. Brant in this thread?

alt. wiring help

If so, what we really need to know is, what does that extra black wire with the female 1/4" faston flag terminal (try saying that 5 times fast) go to, and what part is represented in the schematic? It's NOT the starter solenoid. . . .

mxracer21cba · 02-27-2005, 01:11 PM

Thanks Guys for the help. The red and white wire from the alternator the large one connects where? to the one side of the brown resistor block i take it. And the black wire from the mark 10 capacitive discharge i think is the power in connects where? last question a pale yellow wire with the end cut off runs along the oil lhose line to the front of the car any idea what this is for?

thanks

Early_S_Man · 03-02-2005, 11:32 AM

Quote:

capacitive discharge ignition???

i put a post up for help on the electric for my 68 911L. The help i recieved was great and i have pretty much everything figured out thanks to the pictures and the advice of you guys. One last problem is giving me trouble however. the car came with a capacitive discharge ignition called a Mark 10B. I figure out how it hooks up to the coil but i cant figure out where the black wire goes (which i think is the power for it) Correct me if im wrong on anything and please let me know how i can get the key turned on my project.

To keep all info together related to your Mark 10B CD system ... I am answering here ...

The black wire from the Mark 10B is a ground wire that needs to be secured to a clean chassis ground on a bolt or stud. Power [+14 Volts] comes from the former '+ coil' lead/connection via the Red wire from the Red terminal strip/board.

B D · 03-02-2005, 11:51 AM

I think you got it all figured out, Warren is the man when it comes to electrics. I have a 68 911L Sporto as well so if you need any help/reference just let me know. Where you located and lets see some pics.

Superman · 03-02-2005, 11:56 AM

Now, how is this young man supposed to get answers from the teentsy little bit of information you have provided, Warren? Sheesh! I mean, if he prints this stuff out, he'll only have about a wheel barrow full of documents that directly relate to his installation.

Of course I am being facetious. Funny thing is, Warren's impossible level of Porsche 911 understanding does not exactly end at electronics (for which I suspect he may not have an equal, worldwide). If I ever need to know exactly how tall a titanium Porsche 917 wheel hub is and the various fitment problems the Porsche engineers in Stuttgart may have had to solve thirty-five years ago, I know who to ask.