New master cylinder install on an '86 questions...

ChrisL · 09-03-2003, 03:55 AM

I'm replacing the master cylinder on an '86 Carrera and have a couple of quick questions:

Does the new master cylinder come with brake switches (sure looks like it does from the pictures)?

If I have two-pole switches on my old one, and the new one comes with three-pole switches (as shown in the picture from the catalog), do I just plug my two-pole connectors into the three-pole switches? That would leave one floating in a recess in the connector that looks like it was designed to do just that.

Thanks in advance,

Chris.

BGCarrera32 · 09-03-2003, 05:18 AM

Yup. I ran into the same problem on my '84 2 weeks ago when I did the master cylinder as well. If you *gently* take a flat head screwdriver you can pry the spade connectors out of the white cylindrical plugs on the wiring harness. Then plug them into the 2 tabs on each switch ignoring the 3rd tab, and wrap up with some electrical tape.

And voila, brake lights...(after you refill with fluid and bleed of course...)

-BG

ChrisL · 09-03-2003, 05:57 AM

Brian,

You mean that semi-circular cutout isn't so the connector will fit a two-pole switch or three-pole switch? Did your connectors look like this:

Chris.

BGCarrera32 · 09-03-2003, 06:24 AM

Correct, it will not fit, and you'll find that the spacing between the 2 plugs does not match the spacing on the terminals of the switch anyway. Hence, I had to pop out the spade connectors from the white thing you are holding and plug them onto the switch seperately. No big deal though, the white plastic part doesn't really help lock the connection anyway...

I suspect the 3 pronged switch has the 3rd terminal for a shield, which really isn't needed anyway.

89911 · 09-03-2003, 09:22 AM

Couldn't you just take your old ones off you old MC and replace them onto the new one? That is what I did with a turbo mc when I replaced mine.

john walker's workshop · 09-03-2003, 09:30 AM

the third wire relates to the red light on the dash, which tells you that the brakes have lost pressure front or rear, like you wouldn't have noticed.

BGCarrera32 · 09-03-2003, 09:33 AM

Quote:

the third wire relates to the red light on the dash, which tells you that the brakes have lost pressure front or rear, like you wouldn't have noticed.

That's a good light to have come on, way down there by the radio, when you're going oh-sh-- and grabbing for the e-brake handle...

ChrisL · 09-03-2003, 02:29 PM

Michael,

I wanted to replace the switches anyway because the stop lights don't come on as 'soon' as I'd like them to. Separately, they're $21 each! So I think I'll take Brian's suggestion. And Brian, are the two prongs that I want the ones that are opposite each other?

Chris.