clutch pedal box retrofit

[WreckITFrank]

Spent a few hours swapping a td5 pedal box. Seems pretty straightforward yet getting my ass kicked.

Lof master and spring. Td5 pedal box, as far as I know. Bled for a while and getting a firm while at bottom of engagement. But the rod in the master is hitting the rear wall of the box. Could the throw of the master be too long? The 5.5" measurement, I can't seem to achieve that, should it be done without the spring? The newer style box the spring hold the pedal way the way up, out all the way down. We pulled the slave and it's pressed out, and the rod seems lose on the fork but still attached.
The best I had so far was if I pulled the pedal up, it would quickly spring against the bulkhead. If I fully push it, it will lock down. If pump by hand, the lower end of depress had a little resistance. Not sure how the pedal stop works, as it doesn't push the pedal off the floor enough to really stop anything.

Open to any suggestions. Thanks

 

[WreckITFrank]

I have not considered if the fork is botched. The whole reason was I would lose pressure while driving. Then after stopping, and pumping for a while, it would build up again and I was fine.

If we engage the rod on the fork, you can hear and feel engagement on the (a good bit of play). In and out are fine, not much up and down.

 

[Napalm00]

Let me know how it goes cuz I'm supposed to do this project before I swap my motors

 

[WreckITFrank]

Right now the pedal is about 1/2" too high if setting up as the manual states. 5.5" if there your want to be, I'm at 6 but the piston is bottoming on the back of the box. I'm guessing the I need to be properly pressurized before I can get my 5.5". I have pedal return not so doesn't lock downward, just upwards.

Manual attached for reference

 

[javelinadave]

You definitely need the system filled and bled before you can get a proper adjustment on it. Needle nose ViseGrips to hold the rod while turning the set nuts man the job much easier. Without holding the rod tight the job generates a lot of fouls language and the garage becomes not very child friendly.

 

[Tomaco1]

Sidebar, and I am sorry for your troubles, but do you get my spring in that shipment?

 

[WreckITFrank]

Sent you a text

 

[Red90]

The instructions posted above are wrong for the new style pedal box. Those boxes do not include an "up" stop and are intended to have the pedal pull on the master in the up position. Basically you adjust the rod to set pedal height and that is it....

Personally I think the new design is retarded and add an up stop to my boxes. This prevents tension on the master when up.

 

[WreckITFrank]

I may do that as well once i get it sorted. Didnt get too much help yet from LOF. I may remove one of the jamnuts from the MC side of the trunion to get some more threads, im still 1/2" too high. I am leaving the pedal pressed by a wedge for now to gravity bleed. I have a firm pedal, but it's all out of alignment.

 

[Napalm00]

1/2 too high doesn't sound like an issue really ? does it work ?

 

[Red90]

1/2 too high doesn't sound like an issue really ? does it work ?

The problem is that the rod it hitting the back of the box. He needs to adjust it to stop that happening.

 

[WreckITFrank]

After working on it today I am convinced the throw of the LOF master is longer than stock. That said, I threw the manual out the window as changing the spring and MC to aftermarket seemed not to really apply anymore. After pulling the LOF spring out, I adjusted the trunion on the MC rod to as close to the brake pedal as I could for height. With the spring off, I had nice pressure on the pedal and good return, so I drove it back and forth in the barn for a bit only needing to adjust the pedal depress stop to allow me to use reverse. Surprisingly enough the pedal felt perfect without the spring, easy engagement and disengagement. It looks like a NTO box being so clean and having near-perfect paint, but still has enough slop in the pivot pin to equal what the manual says is needed for play at the rod end. I get about 1/4-3/8" of play in the rod before it engages. I now have feeler gauge worth of room at the end of the MC rod and the pedal box, and if I pull the box out or when I paint I'll probably drill a hole in the end pedal box to ensure it does not bottom out at all.

So while it technically doesn't line up to the book standards, the clutch seems fine for now. I'll know for sure once I put the spring back on. I am also cutting down the left and right ends of the spring where it goes through the bushings. It's unnecessarily long and with the added thickness of the bushings, it's really a pain to get out if needed.

I feel like I was too hung up on what the manual says in this instance. Spent a few hours the last few weekends wasting time trying to line it up and work out the air which was probably not present.

 

[Napalm00]

Do you have the old master that you can compare it to ? I'm about to do this job myself and am now not looking forward to it even more

 

[WreckITFrank]

I do, I have the original from the 91, and the one that came from the TD5/TDCI box. It's hard to tell though as the LOF MC is slightly different, and I think the dust cover is bigger. In hindsight, I should have compared them on the bench. I actually have a second TD5/TDCI box as well, and while it shows some marks at the back of the pedal box it sits about 1/4" off the back at rest. I also pinned the pedal down for a few days with a block of wood to make sure the air was gravity bled out after I used the mityvac. The motive won't work on the LOF MC as the threads and fancy alu cap are different than LR.

I suggest setting it up and bleeding w/o the spring on. It would have saved me a few hours.

 

[Napalm00]

Woof sucks , thx for the info