Jump to content

How do I convert my 60 Lesabre to a dual master cylinder?


Recommended Posts

I want my 1960 buick lesabre to get a  power brake conversion from a single reservoir to a dual reservoir master cylinder...the present single reservoir master has a clip on cap so appears already to have replaced the original factory installed "box" reservoir that had a four bold attachment to the booster...this one has a two bolt attachment to -I guess- also replaced booster ; which I want to keep.  I do  also want to keep all the original front and rear brake drums- no disc conversion. I am having difficulty finding the appropriate dual reservoir MC: Previous -old 2015 posting - mentions AC Delco part: 18M1027; but it refers to a 1964 Buick Wildcat conversion...Anyone can recommend a dual reservoir MC for a 1960 Buick ?

Link to comment
Share on other sites

  • JohnD1956 changed the title to How do I convert my 60 Lesabre to a dual master cylinder?

I have owned my '60 Electra since '02 and never considered modifying the brake system. I had my original master cylinder sleeved when I went through the brakes. If I ever need to rebuild the master cylinder and can't find a fresh kit I will buy one of the new offshore new ones with the poor casting and use the rubber parts from it.

 

My prickly point about these brake conversions is the transition from the common, older 1/4" tubing to the new small diameter tubing. There are many places that reduction can be made but I have never seen what Google would call "a scholarly article" addressing the difference in tubing diameters. It is a design affecting on the cube root so it is significant.

 

Since my '60 Buick was made about ten years before we put men on the moon and got them back I figure engineering was well developed at the time.

  • Like 2
  • Thanks 3
Link to comment
Share on other sites

It is a prickly point indeed and when it comes to brakes...not something to take lightly !  This 1960 Buick went already through a conversion from the factory installed MC and booster (of the four bolts attachment types) to another booster with a two bolts attached single clip capped MC with integral brake switch - the two point sliding connector. (I have never seen that kind of brake switch integrated single reservoir MC again for sale). But most importantly : it kept the original 1/4" tubing....So any conversion to a modern MC with smaller outlet diameter would require an adapter in between and how that might affect the entire brake efficiency only physics (or hydraulics ) would know. ANY INPUT WELCOME !

I don't know what is meant by "splitting this topic into a separate thread "

Link to comment
Share on other sites

  • 2 weeks later...

OK, so we ruled out the desire for the 4-whl power disc brake conversions many are talking about these days.  That's good.

 

I also fully understand the desire for a dual-circuit brake master cyl, for safety reasons.  ALSO know that many of us lived-through those times when all we had was single-reservoir master cylinder brakes and lived to tell about it.  In a time where most service stations had open gallons of brake fluid on their work benches (as it could also absorb moisture).  So, several possible dynamics at play!  In theory and reality.

 

Many might not understand that when one of the brake fluid circuits is "lost", the remaining circuit still means that 1/2 of the braking power is gone, so stopping distances will be longer as a result.  A crash or collision could still result.  Yet this is one case where "something" is better than "nothing".

 

For an OEM-based upgrade, you might look at the earlier 1960s Cadillacs which used a factory dual reservoir master cylinder.  Perhaps that might be a viable alternative to use or install/adapt to your Buick?  Might be more period-correct, too, if that matters.

 

Although I had not researched it, I was not aware of any changes to brake line tubing diameters, over the years.  Certainly something to consider, as to hydraulic leverage and such.

 

NTX5467 

Link to comment
Share on other sites

I went into RockAuto to learn the differences in the 1960 Buick master cyl and the suggested 1962 Cadillac master cyl.  In looking at the Buck cyl first, I noted that all have the 4 bolt mounting, with the pressure take-off on the top-side of the front end of the housing, with the brake line hooing to the bottom-side of that same end housing.  1.00" piston bore.

 

The 1962 Cadillac master cyl looks like a smaller version of the later drum brake dual master cylinders.  No place for a pressure switch brake light switch.  Same 1.00" piston bore.

 

The Cadillac mounting flange is only 2 bolts, one on each side of the pedal push rod.  When I re-looked at the Buick flange, those two Cadillac bolts match up to the location of the bottom two bolts holes on the Buick flange, which appears it should bolt-on as is.

 

Which further means that about all you'd need is to build the line adapters to run lines to the existing chassis lines past the f/r junction block on the frame.

 

The only other "minor issue" would be to adapt the Cadillac brake light switch to the Buick's brake pedal assy.  I suspect they might be very similar in design, but this is speculation.  But knowing how many unseen items were shared, it might just take a switch and some sort of braekt to make things work, aside from the wiring alterations.

 

Hope this might help!

NTX5467

Link to comment
Share on other sites

  • 2 weeks later...
On 9/13/2024 at 7:08 AM, kgreen said:

I always wondered why the cable operated emergency brake was never named parking brake which is the only time it seems anyone contemplates using it.

Many, like 50, years ago I rode to a local plaza with a friend's girlfriend. The friend's name was Snake. When she stopped the car she said "The shifter is out of adjustment and Snake hasn't fixed it yet. Would you put that rock in front of the wheel?" I asked "Doesn't the emergency brake work?"

 

Suddenly life with Snake got just a little easier. Especially when she drove alone.

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...