Sportomatic info

[Sgrun]

Hi,

Is there a resident early sportomatic guru? I recently added a 69E sporto to my garage & am trying to find info. on these.

Specifically at this point, I need a proper wiring diagram & any info. on trans. adjustment & rebuilding.

Thanks,
Steve

[cfc]

Porsche Workshop Manual.

[Wayne 962]

Is it running?

-Wayne

[Sgrun]

I have the Factory workshop manual volumes 1 & 2- couldn't find anything useful in it.

Well, it is supposed to be running, was just delivered to me. It was driven on the trailer & the truck driver moved it once or twice in between. It had a completely dead battery, so we put the charger on to crank for a while, but couldn't get it to fire.

It appears to have spark & fuel, but won't even fire. Wondering if I fried something with the battery charger?

Thanks,
Steve

[jurhip]

Steve,
Congrats. Try contacting PCA, they may be able to point you in some helpful direction.
I don't think your starting problems are tranny related though.

Personally, I think the sportmatic models should be more desireable from a collection standpoint. The application of techonology in a production car, given the time period, was amazing. The sportmatics even have some race history as teh facotry wanted to "prove" them to the days drivers.

good luck.

[Grady Clay]

Scott,
Welcome to the Forum.
You will find lots of help here.

WOW, you have a full engine compartment – MFI and Sportomatic. All you needed to increase the difficulty is A/C. Been there, done that with all three systems.

Since the 911 drove, the first project is to get it started and running somewhat acceptably so we can do some diagnosis.

What is the history? How long has it sat? How many miles? What prior work, problems, attempted fixes? We want to approach this VERY carefully so we don’t assume anything. No doubt someone at some time has caused some mischief.

The Sportomatic and MFI only interact in the area of throttle position so we can (mostly) consider them independent systems. There is a LOT of good information here (Pelican) on MFI – do a through search and start yourself both a paper and computer resource. I recommend you also copy the exploded diagrams from PET (parts CD).

The electric circuits for Sportomatic are relatively simple (located on p. SR41 of Vol. I, 911 Factory Workshop Manual). Basically there is the switch at the shift lever, two switches at the transmission and the solenoid in the Control Valve. Additionally there is an oil temperature sender and an over-temperature warning light switch.

The pneumatic (vacuum) system and component adjustments are the usual culprits for improper shifting but we won’t assume anything.

First things first. Get a new battery.

Best,
Grady

[Sgrun]

Believe it or not, the car does have A/C - although I did pull the compressor out last night as someone has already removed the underdash unit. It is a Cool-Aire aftermarket unit.

The transmission questions were just for general info. later on. Since I haven't driven the car yet, I don't know what questions I would even have about that.

One curious thing I have discovered is that the solenoid on the sporto control valve is staying energized anytime the shifter is in neutral - even with the key off or removed from the ignition. The only way I can get it to deengergize is to move the shifter into gear.

Clearly I suspect this is not correct as it results in the solenoid getting quite hot. Is this a microswitch or circuit problem at the shifter, or is there somewhere else I should look?

Thanks,
Steve

[Grady Clay]

Steve,

Does all the wiring appear Factory original?

Check to see if the power to the solenoid is switched by the ignition switch.

The ’ground’ side of the solenoid can get ground by either of two circuits: the Gearshift Lever Microswitch actuated (or failed/mal-adjusted) OR via the Gear Selector Shaft Switch being in the ‘neutral’ position and not Park or a gear.

Do the two ground wires join at the solenoid terminal? If so, you can disconnect one or the other to find the source of the ground.

Best,
Grady

[Sgrun]

HI Grady,

Yes, the wiring appears original, there is a two wire plug on top of the solenoid - one is brown w/white from the shifter, the other is blue w/yellow and comes from the middle of the 3 fuses on the left side of the engine compartment. This wire is hot 12V at all times regardless of key position.........

Thanks,
Steve

[Sgrun]

Ok,

Got it running by replacing the PermaTune box with an old CDI box.

Now that it's running, it slips like crazy - I'm hoping it's a clutch adjustment & not a leak dumping oil onto the clutch.

I don't smell any burning oil. I will follow the factory recommendations on adjustment. Any other advice?

Thanks,
Steve

[CliffBrown]

Steve

Make sure to keep your hand off the shift knob if you want the clutch to engage.

It takes the slightest pressure on the shift lever contacts to disengage the clutch thus resulting in the slip. Put the tranny in gear and keep your hand off the shift lever until you intend to shift.

[Scott Douglas]

This might be the answer to my problem...where is the "Gear Selector Shaft Switch" located?
The micro-switches are working well on my Sportomatic but it still isn't shifting right. It's not making the 'usual noises' when in neutral anymore.
All help would be appreciated.
Thanks
Scott
'78SC w/Sporto and A/C and smog stuff (yeah, the engine compartment is FULL)

[CliffBrown]

Originally Posted by Scott Douglas

This might be the answer to my problem...where is the "Gear Selector Shaft Switch" located?
The micro-switches are working well on my Sportomatic but it still isn't shifting right.

Scott

No sure of the correct names or if this answers your question but the switches that disengage the clutch are located on the shifter under the rubber boot.

Is it safe to assume that you know the clutch is disengaged only if vacuum pressure is available?

A big problem with our older Sportos is the vacuum hoses are rather brittle and leak.

[Scott Douglas]

Cliff
Yes, I'm familiar with those switches but there is also a switch that keeps the clutch disengaged when the shifter is in neutral.
I think I've found the switch, as seen in the picture.
I've also been told by the PO (my brother) that there's a connector up above the flywheel on the left side of the engine that has to be securely connected up too. I have yet to check that particular connector.
The ones on the trans (pictured), appear to be OK. I'm betting the Gear Selector Shaft Switch is the top one in the picture.
The car shifts fine when the electrics work so I'm sure the vacuum system is OK.
Scott

[chrisg252]

I have a '75 Sporto and I believe that the lower switch is the "Bridging" switch that locks out the starter if the selector is not either in Neutral or Park. I think the upper switch is the back up light switch. Easy to check the latter- select reverse, disconnect it and see if the back up lights are extinguished.
There are exploded diagrams of the transmission in the PET that are very good. It's a free download on the Porsche North America website.

Chris

[Scott Douglas]

Cool.
Thanks Chris!

[rsr1975]

This site doesn't see to be updated much, but for what it is worth.

http://www.sportomatic.org/