Golden XL Strikes Back

I swear this car does not want me to enjoy it. I got a whole 2 days of driving out of it before the brake booster totally failed and it took herculean foot pressure to eventually bring the car to a halt. I did enjoy it last Friday and Saturday it went to its first car show. Met some really nice people there. Then Sunday whilst grocery shopping there went the booster and it was just one big vacuum leak with the engine revving. (rolling eyes)

Super.

Thus starts this brake post. I think Ford full size 3rd gens have to be one of the most corn-fusing when it comes to power brakes. Allow me to explain.

This is a small collection of 3rd gen boosters. The '65/'66's can have two different booster for power drums. You can have the Bendix version (back row left) or the Midland Ross (back row right). The '66's with power disc brakes use a different Bendix booster which I understand is very rare.

I'll jump to 1968 disc brakes. Again there are two possible boosters depending on the date of manufacture. Early to mid year use the dual diaphragm Bendix (front row left) or the single large diaphragm Midland Ross (front row right) booster later that year.

The thing in the middle is off the golden XL and it's a single diaphragm modified to fit in place of a Midland Ross. Problem is I have no idea of what it was originally off of.

I do not have any 1967 boosters, but from the master parts catalogue, it shows different part numbers for that year. So they seem to unique to '67. Super duper.

The correct Midland Ross for '68 on the right and the "whatever that is" on the left.

Now the astute will notice that all these boosters have lever assemblies on the back of them. Ford decided that the brake pedal would be the same in all 3rd gens regardless of manual or power brakes. As power and manual brakes require a different pedal ratio, a lever assembly was needed between the pedal and booster to reduce the mechanical advantage (decrease the ratio) to prevent over boosting.

Now that's all dandy, except with all these different boosters the lever assemblies aren't interchangeable.

There are subtle differences for even the same year lever assemblies. The one of the left is the '68 Midland Ross lever assembly compared to the '68 Bendix assembly. The holes may line up, but the booster placement is different and the geometry is different. You risk side loading the bakelite input plunger and breaking it using the wrong lever assembly on the wrong booster.

The '65/'66 lever assemblies are deeper than the '68's.

Given all these possibilities and the attrition rates of these cars trying to find a booster assembly that fits your lever assembly is really hard now. It really pays to have an unmolested parts car.

To make matters worse, Ford doesn't go much into the boosters in the service manuals and by 1968 it just says replace unit as a whole if inoperative with no mention of how to rebuild one yourself.

But that never stops me. I see that as a dare.

This is the lever assembly clean and painted for the '68 Midland Ross.

You have to temporarily mount the brackets to the booster before tightening the lower fulcrum bolt to align everything.

Finished lever assembly.

Here's the rebuild kit for the '68 Midland Ross.

The nice thing about Midland Ross is there is no large spring to fight with the case halves as you do with the Bendix or Delco Moraine.

These are the parts for the control valve, these are the old ones changed out. There's not much to it.

I powder coated the case halves and the clamp and breather assembly.

Not to bad for DIY at home.

The problem with putting something else in there that's not specific to the car is precisely this situation. If there are no more replacements, how can you rebuild it when you don't know what to order. I was lucky to have my other XL with a complete original Midland Ross and lever assembly for disc brakes.

I was also lucky as a few months ago I saw a '68 Midland Ross Ford rebuilt unit on Fleece-Bay and I bought it. It cost more than a parts car but given the scarcity, it was worth it. Now I have another '68 Midland Ross to replace this failed Bendix from something else to use on one of the other 3rd gens.

Bench testing my rebuild. Works a treat. Holds vacuum and without the pump I have about 3 full brake applies before vacuum assist noticeably wanes.

As a side note never operate a booster without a master cylinder attached. I learned that lesson the hard and expensive way rebuilding the '66 Midland Ross

Finished that heinous job. I thought it would take an hour to get that booster assembly in. Well 2.5 hours later........... Just didn't want to go in. But it's in and it works. If anything it works probably too well. You can use a feather duster to stop the car now too. If anything it just showcases all the other problems in the brakes. When I changed the tyres the front rotors are really glazed so I'm sure that's contributing to now touchy brakes and it feels like the rear brakes aren't doing much, if anything. When I pulled those tyres off I pulled a rear drum and there was only a spec or two of brake dust so I'm sure the hydraulics aren't working. The mechanical parking brakes work really well. Well now they do, not so much when I brought it home.

Here's quite possibly the most idiotic grease fitting.

I wish you joy getting to that when it's together like this.

I took the carb off and took some secondary throttle plate out (adjustable stop), then adjusted the primary's. Wow this runs really good and incredibly smooth. A part of me still can't get over that (all this is now from junk cars). It may generate the power of a boiled potato, but geeze is that engine quiet and smooth, you can hear the belts spinning is how quiet it is. It is however quicker than my Grand Marquis, not much more, but noticeable. Actually it's slowly turning into a refined cooler version of my Grand Marquis. I'm digging it. After tonight's drive we now have 300 miles on this engine. So far so good.