1987 Gt: Brake Line Fittings Spec (driver's Side Hard Line)

[Eulers]

The car is an 87 GT, I need to replace the drivers side brake line coming off the stock/original master cylinder and going to the brake hose in the fender. The line comes out the bottom of the MC and proceeds directly to the left-front disk brake.

I am replacing the original master cylinder with a OE spec Cardone #13-4005 that I have on order.

I read the August 2009 post on the same topic and wonder if there has been more specific knowledge gained since about the fittings spec.

I have both CuNi hard line tubing & the tools for inverted flare & bubble flare. What are the specs for the End Fittings for this Left-Front brake hard line?

• Are they metric or SAE threads? What size?
• Are they bubble flare or inverted flare?

THanks.

 

[gearheadboy]

The car is an 87 GT, I need to replace the drivers side brake line coming off the stock/original master cylinder and going to the brake hose in the fender. The line comes out the bottom of the MC and proceeds directly to the left-front disk brake.

I am replacing the original master cylinder with a OE spec Cardone #13-4005 that I have on order.

I read the August 2009 post on the same topic and wonder if there has been more specific knowledge gained since about the fittings spec.

I have both CuNi hard line tubing & the tools for inverted flare & bubble flare. What are the specs for the End Fittings for this Left-Front brake hard line?

• Are they metric or SAE threads? What size?
• Are they bubble flare or inverted flare?

THanks.

They are metric. Next I think they are inverted flare however back one out and look to be sure. I very often reuse the fittings off of my brake lines on the new lines and add the flare. Pretty certain an ISO flare or bubble flare was too new of an idea to American cars in 87. The first I remember was about a 91-94 Cavalier.

 

[Eulers]

Thanks Gear Head Boy. Yes, I am in the process of backing out the nuts and boy they are quite fixed bye age, galvanic corrosion, etc. As you say, they most likely are inverted flare given the car's vintage.

As for re-using the nuts, in my case the tube wrenches rounded off the nuts and now I'm left using alternative methods of removal.

So any ideas on the size of the nuts? M10 x 1.0, or M12 x 1.0, or M11 x 1.5?
There seems to be an assortment of sizes used on the Master Cylinder.

 

[Eulers]

OP Update: The MC is a 3-port design and the brake line nuts at the MC I discovered after buying an assortment of nuts. The MC is the original (aluminum) unit. The brake line nut size & type are as follows:

• The port at the bottom of the MC is metric & uses a nut M10 X 1.0 Bubble
• The forward port on the side of the MC is metric & also uses M10 X 1.0 Bubble
• The aft port on the side of the MC is metric & uses M12 Bubble

QUESTION: What size and type brake line NUT is required at the end of the hard line at the Left-Front interface to the flexible brake hose?
(I've not been able to get it apart yet).

FYI - For others, note that while the short hard lines coming off the MC do have metric BUBBLE flares at the MC ports, the short lines have INVERTED flares at their opposing end (at the Proportioning Valve). What a mix & match from Ford! LOL.

FYI - I returned the Cardone #13-4005 MC because although the vendor's website had a spec sheet listing the MC material as aluminum, it was NOT aluminum. A magnet stuck to the Cardone like glue and it was almost 3X heavier than my original MC. I lost $11 in shipping there so beware.