pedal box assembly help

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sadham
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Post Sat Nov 11, 2017 5:08 pm

I am in the process of reinstalling the pedal box (Manual) almost done but struggling to get brake pedal at a decent height.

The long brass bar has almost all its thread in on the passenger side. I can't push brake pedal down.

Pedal is still much lower than the clutch pedal.

Any ideas on what I've done wrong and how to sort out.
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Brianmoooore
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Post Sat Nov 11, 2017 6:03 pm

The long pull rod across the car has a LH thread at one end and a RH thread at the other. An equal amount of thread should be showing at each end. Unscrew it completely, and start screwing into both ends at the same time.
Brake pedal must end up fully up, so that it works the brake switch fully.
sadham
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Post Sat Nov 11, 2017 6:55 pm

Would I need to loosen the pedal box? Iirc the bar seemed to be too long to put it on both sides at the same time
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Brianmoooore
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Post Sat Nov 11, 2017 7:11 pm

Won't taking the clevis pin out at one end give enough room?
sadham
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Post Sat Nov 11, 2017 8:43 pm

not tried that will do so tomorrow, easier to remove the passenger side pin I take it?
sadham
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Post Sun Nov 12, 2017 6:19 pm

Is there something I'm just not getting?

I've been at it for a few hours and can't get the bar to go back on the pedal side.

I've taken the pin out of the passenger side so that I can do them together but it just doesn't go back on from the pedal side. Threads seem fine on it too just can't get the right angle on it I reckon?
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Brianmoooore
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Post Sun Nov 12, 2017 7:02 pm

Are you saying it won't adjust on the pedal side? Won't screw in and out?
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Post Sun Nov 12, 2017 7:04 pm

sadham
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Post Sun Nov 12, 2017 7:14 pm

It doesn't screw in on the pedal side. I have it disconnected from the passenger side. I am rotating the bar clockwise and it just doesn't push into the clamp. I screw it in by hand it'll go in half a thread and then impossible to turn by hand I've tried using force and spanner to try and turn it on but just forces itself back out instead.
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Brianmoooore
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Post Sun Nov 12, 2017 7:20 pm

You need to take the pedal side clevis out, and preferably the pull rod as well, and sort out what is happening.
Can't remember off hand which end of the pull rod has the normal thread, and which is reverse, but either the thread is damaged, or you're trying to screw two different handed threads together.
Don't forget that this is a pull rod, not a push rod, so is very safety critical. Not good if it pulls apart in service.
I suspect the above link will apply to LH drive cars only, so will be totally useless for this.
sadham
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Post Sun Nov 12, 2017 7:25 pm

Was just thinking to try that out, it can be removed without removal the pedal box?

I've even tried the usual curse words I would have thought that would've done it.

Passenger side is anticlockwise so drivers side should be clockwise.

Looks like a job for tomorrow, my shoulders need resting
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Brianmoooore
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Post Sun Nov 12, 2017 7:33 pm

sadham wrote:Was just thinking to try that out, it can be removed without removal the pedal box?


Not sure, TBH. I've only ever tried to remove and fit one on a complete car, and that was fitting a longer E34 rod after moving the servo to the left to accommodate a M50 inlet manifold. Everything would have been out on the passenger side.
I've no recollection of removing the pedal box, but then, I've not much recollection of anything more than a fortnight ago, these days.
sadham
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Post Sun Nov 12, 2017 7:36 pm

Lol yh I know the feeling too well.

I initially took photos of everything while stripping it out but my phone died so has been a real chore trying to get everything back together. Getting there slowly but surely.

I can't just flip the bar around and try the otherside?
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Brianmoooore
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Post Sun Nov 12, 2017 7:44 pm

If the LH end is screwing in and out of the LH clevis OK, then flipping the bar around will present two opposite handed threads together. If a wrong part is fitted, it must be the clevis.
The rod has two flats on it for adjusting with either a 6mm or 7mm spanner. These should be roughly behind the clutch pedal when the rod is fitted the correct way around.
sadham
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Post Tue Nov 14, 2017 9:15 pm

I managed to get the clamps on both sides of the rod with it out the car.

Can anyone confirm how many grooves on the threads should be visible on either side?
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Brianmoooore
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Post Tue Nov 14, 2017 9:50 pm

sadham wrote: Can anyone confirm how many grooves on the threads should be visible on either side?
Whatever it takes to wind the brake pedal up to fully operate the brake light switch when the assembly is in place.
What is important is that there should be the same amount of thread showing on both sides, ignoring that covered by the locknut.

What is, or was, stopping the RH clevis screwing on properly?
sadham
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Post Tue Nov 14, 2017 10:36 pm

OK so if I start them off at say 3 threads either side then turn the bar until pedal presses the switch they will be equally apart on threads?


Not sure it was quite dirty i cleaned it out and it went on. Just hoping it all goes back together smoothly.
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Post Tue Nov 14, 2017 11:55 pm

Pitch on the threads is the same on each end, so, if they start the same, they will stay the same.
If you can get the assembly back in place in one piece, measure the length of the thread and note it down, then screw both ends on an equal number of turns just about as far as they will go, feed the assembly back in, and refit the clevis pins and their spring clips. This should result in a brake pedal that is very low, so wind the pull rod out until the pedal pushes the brake light switch plunger right up, and tighten the lock nut. Final job is to measure the exposed thread and compare it with your earlier measurement.
In theory, 8mm of thread in the pin should be enough, but I'd want to see a bit more than this for safety.
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Post Thu Nov 30, 2017 8:07 pm

Just to update, thank you very much Brian. That did the trick I have the pedals back in place should be starting the car back up soon so will check that the pedals work correctly.
sadham
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Post Thu Nov 30, 2017 8:41 pm

almost forgot, you know the 2 wires that go into the brake switch (One purple/grey and other green/red iirc). Which way round do the go on or does it not matter?
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Brianmoooore
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Post Thu Nov 30, 2017 10:22 pm

sadham wrote:almost forgot, you know the 2 wires that go into the brake switch (One purple/grey and other green/red iirc). Which way round do the go on or does it not matter?
Doesn't matter in the slightest.