1985 Tahiti Blue (was Flur, now ??)

[tmsmini]

The re-learning capabilities of the ECU happen pretty quick. A good 15-20 minutes and it should have settled in, but it is an ongoing adjustment.
With the ACR code reader, you can force a complete reset.

[MPlayle]

Unfortunately, I do not have access to the ACR code reader.

I don't think I ran it for more than about 10 minutes in testing the fixes yesterday.  I need to get it out and drive it some and see how it behaves after some longer running.

[tmsmini]

It sounds like you have it resolved and the code reader will not really provide anything that you don't already know.
If it gets to the point where you want to see what is "in there," let me know and we can work something out.
I will need to retrieve it from the current borrower.
Terry

[MPlayle]

Thanks for the offer on the code reader.  I will consider it for later if needed.

I'm going to finish the remaining "little things" and try to enjoy driving it.

[MPlayle]

Got out to tinker on the Mini a bit this afternoon.  Today's task was to begin looking into the brake issue.

I put the back end up on stands to check and adjust the rear brakes: found they were dragging a lot, so loosened them.

I then put the front on stands to begin checking them and found both fronts locked up!  Now the car has been sitting for a few weeks, so they should have turned freely.  I backed off the bleed nipple on one front caliper and both released.  Pressing the pedal a couple times and it went rock hard with both fronts locked up again.  Release pressure at a caliper and they were free again.

I put the back end on stands to match the front and pressed the pedal a couple times again.  Fronts locked, rears dragging as previously set.  Released the pressure and all 4 spun freely (rears lost the little bit of drag).

Conclusion: something is retaining pressure in the whole system.

As far as I know, there are two things that will make the entire system retain pressure. A) Missing shim under the master cylinder.  B) Bad or wrong master cylinder.

Time to research both possibilities.  I looked for markings on the master cylinders and they both (clutch and brake) look identical. what markings I could find were the same on both.

[94touring]

The master should be just fine, but I'd look into shimming it.  Kind of odd it's intermittent. 

[MPlayle]

Right now it is very consistent about locking up.  It may be because I was under there at part of the mounting bolts for the pedal box.  The stop bracket for the accelerator pedal had been put on the wrong side of the brake/clutch pedal box.  I removed the left side bolt to the tow-board to remove the bracket and reinstalled that bolt.  Then I removed the right side bolt and installed the bracket there for holding the accelerator pedal away from the tow-board.

That may have allowed the pedal box to shift just enough to keep the master from releasing all the way.  Looking online, there is a gasket supposed to be under the brake master cylinder.  I will likely order one and put under to see if that fixes the problem.

[Spitz]

When I found that my new Traveller's front's were lretaining pressuer....and melting the slave rubbers....it turned out to be collapsed rubber brake lines.
If yours arent new...it's something to check

[MPlayle]

According to Dan (supported by exterior inspection) all of the brake components are new.

The whole system (all four corners - single line system) is retaining pressure.  Releasing pressure at just one bleed nipple is releasing the whole system.  This leads me to believe it is not the hoses.

I cannot see any gasket/shim under the brake master cylinder.  I think it was marginal before I was under the pedal box setting up the stop bracket for the accelerator pedal (it is held in place by the right side bolt of the pedal box).  The bracket had been placed on the left side of the pedal box, so I had to remove the left bolt to retrieve the bracket.  I reinstalled the left bolt before removing the right bolt, but it may still have let the pedal box shift just that fraction enough that the "pressure lock up" now happens every time.

I spoke with Jack at 7Ent and he agreed it sounded like a missing shim/gasket under the brake master.  I have that part on order (along with a few other trim bits) with 7Ent and it is supposed to ship Monday - arrival expected near the end of this next week.  At that point, we'll see if that fixes the brake issue.  That "should" take care of the mechanical bits that were needed.

[Willie_B]

Had the same problem. The new master I had put in had the push rod was too long to fully release. Swap master again. Probably could have just changed the push rod but did not want to mess with it then.

[MPlayle]

Hopefully there is room to insert the gasket/shim under the current one and it solves my problem.

I know Dan had to replace the vertical studs in the pedal box for mounting the master cylinders.  They seem just long enough for how things are currently mounted and it looks will be close as to whether there will be enough threads with the shim/gasket underneath.

[jeff10049]

If it has lock washers you can ditch them to get more threads just use locktite. Or thin nylock nuts if you can find them ace has them around here.  I'm not sure how much more you need for it to release  but 10 thousands could be enough to lock up the brakes so thread length may be a non issue unless you have to stack up gaskets. I'm sure shimming will fix it I had the same problem on my last mini on the current one I took the gaskets back out to get less free play they seem to be all over the place on how accurate eveything lines up.

Jeff

[MPlayle]

I will double check the next time I can get out to work on it.

[jedduh01]

Shim away - its a cheap try  - even if a replacement master has a Too long of rod - the shim should help

But- what about a proportioning valve?
http://www.7ent.com/products/pressure-reducing-valve-9-78-to-2000-fam7821.html

what if its not releasing?  Next step?

[MPlayle]

I haven't chased that far.  It would be the next step if the shimming does not work.

[MPlayle]

Got some time with the Mini this afternoon.  I started with trying Dan's suggestion of just removing the clevis pin from the pedal and master cylinder push-rod.  That does the trick of giving just enough more drop in the push-rod for the brakes to release consistently, so shimming with the gasket should fix the problem.  The trick now is going to be fitting the gasket and getting the nuts back on to hold the master cylinder in place.  There are no lock washers present.  I don't have access to a proper shop, so may have to get creative on how to shave down the flange of the master if necessary.  I may also look for a slightly smaller diameter clevis pin.

[94touring]

Low profile nuts?  Or elongating the clevis pin hole on the push rod?

[MPlayle]

I will explore those as options.  The gasket for shimming is supposed to arrive either tomorrow or Friday.

Do you remember where you got the flex line used for the clutch master to slave line?  I like the idea of the braided flex line if the hard line from the top of the brake master won't reseal if I have to disconnect it to get the shim/gasket underneath.

[94touring]

Probably got it from minispares.  You should have more than enough hard line available given the small amount of shimming required.  You'll find that when you disconnect from the top of the master it will pull away and clear without having to undo it from the next connection down line.  At least typically that's how it goes. 

[MPlayle]

The good news: shimming works!  The better news: there was enough movement in the hard line to do the work without having to disconnect it from the master cylinder - no bleeding the brakes required!

I will even be able to reuse the original clevis pin as it raised the master just enough to give extra play between the two and the pedal drop just enough lower than the push rod.

71.gif

[94touring]

Good  4.gif. Usually the simplest things. 

[MPlayle]

I will start another thread for this next bit.  The FI is better since the vacuum line replacements, but still has some hesitation spots - occasionally from idle, mostly when trying to give a small acceleration while cruising, such as starting up an incline.

From the research I have been able to do, it is likely an aging sensor.  The problem: most of the sensors are now NLA.

So, I will be converting it to a carburetor.

[94touring]

Hence the fuel tank? 

[MPlayle]

Yep.

See the new thread.