I have use a dozen of these before with little or no issue, until now that is. I'm no brake dummy, not my first rodeo but these brakes feel like crap. Spongy pedal and won't stop for shit. The 5w I have been working on just won't leave. We have had some serious teething pains to get this thin out the door. It was supposed to leave Christmas Eve but a bad (new) torque converter trashed the new trans, brake issues out the wazoo and so forth. Trans problem is now fixed, so here it the break down. Speedway Motors 35-40 brake set up on one of my bolt-in FullX crossmembers and a 1" bore master cylinder. The pedal pushrod to master cylinder alignment was far off enough to cause a bind and not allow the master cylinder to return fully. So I made the decision to scrap the customer supplied cheap-o brake pedal for one of my own kits and reusing the Speedway master cylinder. Unimpressive brake pedal feel, the 1" bore master should have had a better pedal feel, felt spongy like it still had air in it. So off it comes, bench bled it to death and determined it was bypassing internally by shunting off the output ports with plugs. You could push on the piston and it never firmed up and would creep a small bit. So in the circular file that POS goes and in goes a brand new Raybestos 1967 Fairlane 1" bore four wheel drum master cylinder. Bench bled out nicely but not getting much of a jet of fluid out the compensation port. Once installed we could actually get a pedal but only an inch or so from the floor, ggrrrrrr. Everyone suggests 10# residual valves, I rarely use them and for me they have never solved a brake issue. But I'm getting frustrated with this thing and install a set. And per my experience with them, nothing. No difference whatsoever in the pedal feel. So the next step is a larger bore master cylinder. My pedal ratio is 6:1 so I expect a slightly softer pedal but not like this. To my surprise, the 1 1/8" bore master cylinder from a 67-72 F series 4 wheel drum truck also did little to improve the pedal feel. The car will stop but the pedal feel is soft and not confidence inspiring. Took the weekend off the car to think of a new plan and where I could have gone off. The rear is a 67 Bronco rear with the small drums and the front has the MT Car Products Lincoln style brakes. The only thing I could even begin to assume was the shoes were arched wrong and flexing under pressure. So this morning I pulled all four wheels and drums, the rears don't look too bad but the fronts have a very small contact patch high up on the shoes. The shoes fit the drums well, good contact save for the lead in and out as it's supposed to fit. So here is what I think is the problem, the anchor pin is set too high in the backing plate. It is slotted for some adjustment, I have it all the way down in the slot. I think the best solution is to grind out the hole to get the shoes down a bit further and hopefully that solves this spongy pedal issue. ____________________________________________________________ Let me know if anyone else has run across this issue before. I will update soon with results.
It seems to me there was a thread on this same subject and manufacture – MT Products. I can't pull it up right now, but Richard Lacey of the Early V8 Store is an expert on these brakes. Maybe he will see this post and respond.
Try this on for size. At first Richard said the pin was too low then backed up thinking about this situation. When he was first dealing with the Wilson Welding backing plates, the anchor lug was too low and he made the lug eccentric to raise it up about 1/16"..... So I just did some mental gymnastics and the more I thought about this situation, the more I'm convinced that these lugs are too high and here's why. First pic is the shoe sitting in the drum, fits nice. Second pic here, I pushed the top of the shoe up about 1/16" up and the bottom of the shoe comes away from the drum. This is consistent with the wear pattern on the shoes. Got some grinding to do...
On the original Lincoln brakes the upper anchor is slotted also, and is set up with a .010 feeler gauge at the top edge of each shoe. The original drums had a slot in the side to insert the feeler gauged and then set the upper anchor and lock it down. With the absence of the slot in the new drums I tape a long feeler gauge across the top of the shoes and set the upper anchor. Arching the shoes to the drums also helps a lot, as well as setting up the rear brakes fairly tight. I use 15/16" wheel cylinders on the rear also.
Huh? If the tops are hitting first, the shoes are too high, right? So lower them. Or maybe the bottoms of the shoes need a little adjustment outward as well.
hmm........ hard to say without looking at/feeling etc.... in person. but I feel for you, i've chased poor feeling brakes myself. after looking at pictures my thought is your shoe contact pattern isn't too terrible, it seems with working adjusters it will only get better with use. acouple thoughts; brake hoses are old/poor quality and expand under pressure. wheel cylinder size is to small or not enough front brake bias. possible try capping off rear lines and drive... then rear only.... might add more info....
If you have a spare drum, you can make some windows to see what is going on. Do they adjust OK, a nice constant drag? Also, how much of the adjusting star do you have to use to adjust them? Good luck, this kind of deal can drive you batty. -Abone.
I had a similar problem on a pair of drums recently. They were for a 9", but it turned out I had the wrong style star adjusters. There are two types: one type the slots that index to the bottoms of the shoes are squared off, and the other type they are tapered. I had squared off ones, which were hitting the arc of the shoe, and not letting the adjuster slot seat properly on the shoe. All I had to do was chuck the adjuster ends into my lathe and turn the taper into the ends. No more weird wear patterns after that. I'm sorry, but I just looked and the pics must be on my old phone. Something simple to check visually before you start grinding.
I'm thinking my problem had the wear on the bottom of the shoes, not the top, so I don't think it will help.
Here's the wrap up: I opened up the hole in the backing plate to allow the pin to drop another 0.100" lower, did the whole procedure to align the pin again. Found that the pin needed to be lowered just a touch over 0.050" below where it was (max adjustment down) And here is another thing, the shoes are now concentric to the backing plate! With nothing else done to the rest of the brake system, the brakes feel fantastic now. Confidence you can stop, and that's always a good thing!
There ya go. Without drawings its hard to say if its the pin or the shoes. You know how these things go, MT says "oh such@such shoes are the same as these&those shoes we can put these&those in the kits" but they ain't exactly the same.
As with any issue like this, once it is fixed you can look back at it and see how easy it SHOULD have been to fix. But it never is. Glad you got it wupped, gonna keep this one in the mental tech archive. -Abone.
Always appreciate troubleshooting with a well thought out and explained solution...and pictures! Thanks again Steve.
Thanks for posting this, Steve. Great info to keep in mind on future projects. Are those rear tires from Towel City? If they are, what do you think of them? Good quality and something that might be a good street/strip tire?
Yes, Towel City cheaters. Only have a mile on them so far. Tomorrow I reset the valves and finally get to actually drive it.
I did my last 2 32 roadsters with MT brakes on both ends and used a 66/76 Jeep truck mc and they seemed to have adequate stopping power. Drove the current one in LA traffic this summer with no problems. I think I'll pull the fronts apart and check the wear pattern. I did Wild Turkeys 32 Modified roadster PU with Wilson Welding on all 4 corners and last I heard he had over 30,000 miles on it. That said I agree that there is room for improvement and I'm doing MT's on my new 32 PU and I will be following Elpolacko's lead and pay more attention to the wear pattern. As a side note I've done quite a few customer chassis with MT's but haven't had much feedback.
Could anyone reveal what brake shoes and other parts fit the MT backing plates? Other posts here on Lincoln brakes for the Wilson plates mention over the counter shoes, wheel cyls, and mounting hardware (76 Chevy Caprice wagon shoes/mounting hardware, 67 Ford wheel cyl). Do the MT plates use the same parts? What anchor pin and star adjuster is used on the MT plates? Thank you for any help!
Thanks for this write up I’m having issues with my front MT brakes . I’ve had everything apart multiple times trying different things but haven’t opened up the anchor slot yet. I believe this will fix my issue after seeing yours.
Thanks for sharing this! One thing I did on my 32 (F250) fronts, that I think Dennis Lacy suggested, was to snug up the nut holding the top pivot pin, apply the brakes tight against the drum, and then tighten that big nut. I still don't have a firm, hard, high pedal so it's back to it again. Very frustrating not to mention time consuming.
There are so many variables that could cause the lack of "firm and high pedal". Couldn't it be anything from master and cylinder diameters, to pedal ratio, to shoe lining material? This is all even if the shoes are perfectly arced and bedded in. And I've never found a chart or spreadsheet showing how modifying one variable will affect the brake's operation.
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