75 Automatic neutral switch

[MD]

Where is the neutral switch located?

1 In the console next to gear lever?
2 In the transmission itself?

Thanks.

[four90s]

Hi MD,

It's in the trans. Just in front of where the selector lever goes in there should be four wires coming out. They should be pink, green, black and white. IIRC the black and white are the lockout wires.
(Pink and green are reverse light.)

That's what I used when I built my auto 90. Never actually run an auto 75. Well apart from on and off the trailer of course.

Cheers
Steve
Adelaide

[MD]

Thank you Steve. Saves me going for mining for boloney switches. I hate pulling that console apart. 

[MD]

Steve,

Some correction is required here regarding the wire colours for connectivity. The black and white wires ARE NOT THE STARTER MOTOR CONNECTIONS (starter inhibitor/neutral switch)

The correct wires are : Black & Green with Black stripe fixed to the contacts as per attached photo.

This switch actually opens and closes circuit when the internal push rod is either "in" or "out" and this relates to the appropriate function of reverse light or starter motor.

[four90s]

Bugga,

50% chance of getting it right, as I no longer have the car to check. It's gone to Alfa heaven, as it was the rustiest 90 I've had. Pity too, as it was also the newest, being a late 1987 build.

Hope my incorrect suggestion didn't stuff things up too bad.

Cheers

[MD]

Not at all Steve as it got me started on sorting the intermittent problem out. The location is correct and so this was the start of it all. After some trial and error with ohm meters I got it worked out followed by actual testing to verify things.

Until I can get a replacement switch, I have simply hot wired the inhibitor side so that we can get constant starting. Naturally, it is essential to place the gear selector in neutral or park to avoid the engine trying to start in gear because it will . Much like starting a manual in neutral. No big deal. The main thing is the car is now dependable like it should be and I am grateful for your interest and assistance to get me there.

[four90s]

Good-oh. I've probably got a spare switch if you need it.

I've got two trans here, one that has a very loud set of pinion bearings and one that has a whinging pump.
When the next 90 auto project gets to the top of the list, I'm going to make one good one out of the two, but until then, they are just sitting around.

Let me know if you want me to send you one. If it's good, you can send me some $$.

Cheers
Steve

[MD]

Steve,

For what it's worth, I was having a chat to a friend of mine that operates an automatic transmission service small business. He specialises in European transmissions. He was telling me what a well made little box they are. He said to me he had pulled one down for a 300,000 Km service and he said it showed virtually no wear at all. He was full of praise for these ZF transmissions.

Apparently the core of the transmission is used in a number of other makes of cars using appropriate ad ons to fit the different set up and Alfa is just one brand user. The ZF designation is a 3HP-22 unit for spare parts purposes. I believe the Peugeot 505 uses one Citroen CX and BMW 520 also uses them.

Thanks for the offer of a switch. I'll send you a PM and we can work something out.