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Bleeding the MDL is easy , get a large syringe that will hold 35 cc's of fluid. Now on the slave put a piece of tubing and put a p-trap in it and run that into a bottle, now push the syringe into the hole in the bottom of the resevoir and push the fluid threw. They told me that 35 cc's was more then enough to get a good bleed. I did this in 2 minutes and it's been great ever since. Hope this helps
 

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As promised, a year and a half after installation both the Wilwood master cylinder and ? slave cylinder have started leaking on my MDL T5z conversion. I have to stay hydro because of my legs and that I lowered the brake master cylinder covering the original firewall clutch hole. Probably going with the Tilton puck style throw out bearing and universal slave cylinder. Why can the OEM's make the same components last 20 years and a couple of hundred thousand miles while the aftermarket can't make it last 2 years? Spending money twice as usual.
 

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Some of the slave cylinder kits tend to side load the piston and this will wear it out. If you can configure a clutch slave so that the rod is a direct push on the piston, they will last much longer. I fabricated a bracket for a Wilwood pull type slave that was bolted to the motor mount. Used a stock type 5.0/T5 throwout bearing and clutch fork. The line of pull was direct and the slave was working well when I sold it 3 years later.
 

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This is a pic Nailbender uploaded in another thread.
This is what I'm talking about. If it doesn't have a straight shot to the clutch fork, it will tend to wear on the side of the bore. that could have been easily prevented by moving it down a fraction of an inch.


This is the one I built for my Cobra, it attached to a Prothane Motor mount in the front with a bracket I made from a piece of angle iron. I never had a problem with it.
 

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Interesting and timely thread. One of the biggest disappointments of my Mustang career, was removing a Z bar expecting feather light touch of a Hydraulic clutch. I designed a system that would execute the exact same leverage as the Z bar - did all the calculations and found my pedal pressure was EXACTLY the same. Lesson learned, Z Bars (reinforced so the won't bend) work great even bone stock.


My Willwood / 85 Corvette slave has worked great for well over 7 years but this weekend it Chit-the-bed. NO leaks but it just makes a scraping sound and isn't working right. I'm coming to the conclusion that I bet I designed in the same flaw MDL did - betting its the offset I had to build in to use the original pedal hole. Just reading this today, it dawned on me that there is a Moment imparted by the offset that must be countered in the master which I totally neglected, likely the same problem with MDL. So, now if I move the pivot point on the pedal, I will have to enlarge the diameter of the master to get the same leverage or travel that I need down below. Guess that is this winter's project...
 

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I matched the bore dia(13/16) between the Master and Slave. I get a full 1.5" of travel. Pedal effort is very light.

During the stroke on the master, there is some up/down movement that may create some minimal side loading, but it would be minimal.
 

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I designed a system that would execute the exact same leverage as the Z bar - did all the calculations and found my pedal pressure was EXACTLY the same.
That's real world physics. The only way to get noticeable difference between linkage, cable or hydraulic is to have difference in the leverage, or some unnecessary high friction in one of the systems.

A unknown solution for people that need a really light clutch pedal, may be a vacuum booster. Some offroad cars have a clutch-booster stock from the factory. This show the mounting of an aftermarket conversion kit on a Landrover: https://www.briandorey.com/post/fitting-a-redbooster-clutch-servo-kit-to-an-td5-landrover-defender
 

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Timely thread for me as well. My MDL clutch linkage pooped the bed a couple of weeks ago. Car only has a couple thousand miles since the rebuild. When I press the clutch pedal, the whole thing side loads and pops to the right. Same issue as the OP. The lever plate that mounts to the firewall has a lot of wear on the right side as does the lever itself. I had to buy a whole new master cylinder kit. Tried to install the new plate yesterday and I can’t get a thing to line up correctly. Maybe the original holes were drilled wrong or maybe I’m a moron. Don’t know which, but I can’t get the firewall plate to line up with the master cylinder actuating rod and the linkage off the clutch. Doesn’t help that I’m doing this on the ground in an alley and I’m not as bendy as I once was. Super frustrated, as this looked to be a simple install. Looks like my mechanic will get a few more of my dollars. Oh, and the tow truck driver too......

Edit: 1, don’t know why the pics uploaded sideways. 2, as I look at larger pictures on my iPad I see the system was not installed correctly from the start. The lever plate is too far to the left.
 

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When I press the clutch pedal, the whole thing side loads and pops to the right.
It looks to me like some bad engineering. The pushrod from the pedal don't push in line with the lever and the linkage to the cylinder. That means a lot of side load on the lever every time the pedal is pushed down. The connection between the lever and firewall bracket seems to be a bad design for handling a lot of side load. A wider or double connection would have had a lot more side load strength.
 

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Timely thread for me as well. My MDL clutch linkage pooped the bed a couple of weeks ago. Car only has a couple thousand miles since the rebuild. When I press the clutch pedal, the whole thing side loads and pops to the right. Same issue as the OP. The lever plate that mounts to the firewall has a lot of wear on the right side as does the lever itself. I had to buy a whole new master cylinder kit. Tried to install the new plate yesterday and I can’t get a thing to line up correctly. Maybe the original holes were drilled wrong or maybe I’m a moron. Don’t know which, but I can’t get the firewall plate to line up with the master cylinder actuating rod and the linkage off the clutch. Doesn’t help that I’m doing this on the ground in an alley and I’m not as bendy as I once was. Super frustrated, as this looked to be a simple install. Looks like my mechanic will get a few more of my dollars. Oh, and the tow truck driver too......

Edit: 1, don’t know why the pics uploaded sideways. 2, as I look at larger pictures on my iPad I see the system was not installed correctly from the start. The lever plate is too far to the left.
MDL has come out with an improved linkage, call them up and have the details about when you bought it, and they will get you another one.
 

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It looks to me like some bad engineering. The pushrod from the pedal don't push in line with the lever and the linkage to the cylinder. That means a lot of side load on the lever every time the pedal is pushed down. The connection between the lever and firewall bracket seems to be a bad design for handling a lot of side load. A wider or double connection would have had a lot more side load strength.
At his point I’m not sure if it’s bad engineering or bad install. It looks like the plate that has the lever pivot point is too far to the left. Unfortunately this is beyond my level of patience and time, oh and probably skill. I really only have a couple of hours a week I can work on the car, at this rate I will have fixed this by 2026. I’m mostly pissed that I’m not out driving. I’ve missed three weeks of the best time of year to be out.

MDL has come out with an improved linkage, call them up and have the details about when you bought it, and they will get you another one.
I spoke with MDL, very nice folks but unfortunately no help. Even sent them a video and pictures. They just sold me an entire master cylinder kit. Linkage looks to be the same as what’s in there now. It does seem that with proper engineering and installation they could do without the Heim joints. But what do I know?
 

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I spoke with MDL, very nice folks but unfortunately no help. Even sent them a video and pictures. They just sold me an entire master cylinder kit. Linkage looks to be the same as what’s in there now. It does seem that with proper engineering and installation they could do without the Heim joints. But what do I know?
The upgraded linkage has bushings in the joints and should eliminate the wear you have now.
 

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At his point I’m not sure if it’s bad engineering or bad install.
Bad engineering..... there's a lot of side load in the basic design and the pivot are not designed to counteract this. Here's a 6 year old video from a guy with the MDL linkage in an Ranchero. The same problem with the side load bending the linkage:
 

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The upgraded linkage has bushings in the joints and should eliminate the wear you have now.
Hopefully they’ve improved the design and I won’t have any issues once replaced. I do notice the pivot point seems more robust on the new unit. I’ll keep my fingers crossed. Thanks a lot!

Bad engineering..... there's a lot of side load in the basic design and the pivot are not designed to counteract this. Here's a 6 year old video from a guy with the MDL linkage in an Ranchero. The same problem with the side load bending the linkage: https://www.youtube.com/watch?v=QeIk0nYdu2Y
So that is exactly what mine is doing. If it really was a poor design and not an install issue, that would be great. It seems like this was a known issue, as even Bruce commented on the video. Surprisingly the guy I spoke with, who said he consulted an engineer knew nothing about it. Granted this was six years ago, so maybe the guy I spoke with was new. The guy who built my car did it over several years, so perhaps the MC was purchased a long time ago. Hopefully this will take care of the issue. Thanks a lot for posting!!!
 

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Hopefully they’ve improved the design ..
Easiest improvement would probably be to change the pivot of the arm into a piece of tube, similar to how Ford pivot the pedals. Then you would need MUCH more force to actually bend the linkage sideways. There's even space on the backing plate mounted on the firewall to do it.
 

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Bad engineering..... there's a lot of side load in the basic design and the pivot are not designed to counteract this. Here's a 6 year old video from a guy with the MDL linkage in an Ranchero. The same problem with the side load bending the linkage: https://www.youtube.com/watch?v=QeIk0nYdu2Y

Talk about a rube goldberg setup! Seems to me all that needs to happen is to move the pivot on the clutch and get a smaller diameter master cylinder or larger diameter slave. What am I missing here?
 

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Talk about a rube goldberg setup! Seems to me all that needs to happen is to move the pivot on the clutch and get a smaller diameter master cylinder or larger diameter slave. What am I missing here?
They are trying to align the linkage hole in the clutch pedal with the hole in the firewall, and allow enough room for the clutch slave and the brake booster to coexist. There have been others built using an off set rod, and another mounting the clutch slave at an angle, but that one can be difficult to bleed. If the MDL linkage is installed correctly, they can be problem free.
 
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