915 model nbr and speedo help please

[Hoghead]

I bought what was described as a rebuilt 1985, limited slip, 915 box sight unseen. Now that it has arrived in Thailand, I am not sure what I received

Stamped on the bottom of the box is:
915/6112 718 5747
What does this tell me?

Both flanges rotate in the same direction, so I am presuming a LSD - is this a valid assumption?

I do not see any sensor for the electric speedo and the only sensor is a switch on the nosecone. Is this a reverse switch?
Where does the speedo sensor go?

There is no lever arm on the clutch release shaft.
Does anyone have one, or what else can I use?
Machine work here is cheap, and I have bought the Aircooled.net hydraulic clutch kit only to find that it is LHD and will need a new MC bracket

What is so special about Swepco oil?
It is not available here and I was thinking of a synthetic gear oil

Thanks
Robert

[Turbo Haraune2]

The switch in front if for rewerse lights
If you cannot make the driveflanges turn opposite directions its a locking or lsd diff inside

[Hoghead]

I thought it is a reverse switch as it is plunger operated and simply on or off.

Where does the speedo sensor go?

Any input on my other questions would be greatly appreciated

Robert

[Wally]

Yes, its an original limited slip. I can tell by the model number ;)
Please send it to me! :-)

[Hoghead]

I have researched the box code part of my question, IE
915 = 915 box
61 = 911 SC (ROW)
12 = LSD
718 = 1978
5747 = sequential box serial number

The big problem is that this should be an electric speedo box, but the speedo hole is plugged. The plug appears internal?? and not a simple frost plug type that I can easily pop. See pic:

I need an electric speedo output - any ideas or suggestions?

Robert

[Turbo Haraune2]

Autometer har a universal signal generator for speedo signal.
Gives out a square vave.
I use it coupled to the original speedo wire.

[Turbo Haraune2]

where did you find info about the partnumber on the box?

[Hoghead]

Another answer to my question from Pelican Parts:
http://forums.pelicanparts.com/showthread.php?t=171480&highlight=speedometer+pickup

It appears that the sensor "looks" through the case and "sees" a rotating magnet.
Most likely a simple reed switch, and the speedo counts the number of switch closures, but I am guessing here. The sensor is available from Pelican Parts in the States for 130.00, so if I am right it is an expensive reed switch but I need it. The more I think about I may give it a try with a reed switch, as by the time it lands here it will be 200.00 USD

The Pelican technical forum is a wealth of info on P cars, and where I found the box code info. There is also an interesting discussion of Swepco gear lube which answers my other question, but since it is non-available here I will use a GL-5 rated synthetic.

Now I just need the lever arm to connect to the slave cylinder

[wrenchnride247]

Hoghead, I've got the complete sensor w/connector block and rubber boot. (it has VDO stamped on it) It came with my '85 915. If you pay $20 US plus shipping... it's yours. ;) Will post pic's if you want.

[Hoghead]

Wrenchride
You have a PM

[wrenchnride247]

Hog
you have PM ;)

[Eatoniashoprat]

Autometer har a universal signal generator for speedo signal.
Gives out a square vave.
I use it coupled to the original speedo wire.

Don't mean to hijack but is this (http://www.autometer.com/cat_accessoriesdetail.aspx?vid=114) what you're talking about? Does it thread right in? I would like to try something like this on my 69 bus. It has an OBDII subaru and the ecu wants a speed signal. I have a timer circuit built but it only puts out one speed all the time.

[Hoghead]

The 915 box has a plate attached to the diff with 8 magnets oriented N-S so that one pole is looking at the sensor lockout in the case. A reed switch is a 5.00 device that will close in the presense of a magnetic field. As each magnet passes by the switch closes (8X per revolution) and the speedo counts these switch closures.

I am using a set of Classic Instruments gauges and they have an interface box to change to the standard GM 16 pulse count.

Hall effect, and promimity sensors are different in that rather than being triggered by a magnet they "see" a passing toothed ring.

I am going to need a speed signal for my Subaru ECU as well.
How do the 915 box boys do this?