A Couple More Rainy Day Upgrades

Seattle is suffering from the season - endless rains and cold now prevail.  In order to keep my own spirits up in preparation for my departure to the Caribbean in three weeks I found some small items to upgrade.

First, I saw recently that Walloth & Nesch in Germany sell insulation pads for the floor of the car. They are not stock to my particular year but I ordered four of them in hopes that some more sound deadening would result.

After pulling up the carpets and installing I immedately noticed an appreciable reduction in road noise during my first rainy drive of the day. They cost 10 Euros each and are well worth the price, given how thin yet heavy the material is, which I doubt I could find in old carpet padding.

On a different note, a week or so ago I noticed, in the German 2002 forum Marktplatz, a delicious-looking spread of NOS Nk parts. I fired an email to the seller and turns out he was a certified BMW NK tech as far back as 1966 (he thoughtfully provided a copy of his 1966 factory certification by email).  He had a collection of tasty parts and I grabbed an NOS horn pad from him. The pad even included brand new plastic studs for affixing it to the wheel hub.

I'd been looking for a new pad for years, to replace the one on my car mostly ruined by a PO who tried to "improve" it by recovering the exterior in nasty brown vinyl, as seen in this old photo.

And now replaced.

 

So let it rain, I say.  My car is now drying off in the garage and the temperature is agreeably warm in the house.

Temperature Gauging

My old mechanical temperature gauge failed. Alas.  I found another mechanical gauge but was reluctant to install it.

The gauge assembly date was December 1967 and frankly, the braided wire was quite brittle. After fifty years there was nothing about to reassure me that it would work for much longer, either.

So I found a later electrical gauge and sender unit to match. The gauge date was 1982 and the sender itself brand new!

A quick check comparing the two senders confirmed that the newer version would be a perfect fit.

Then it was time to return to Midnight Motorsport for the swap.  First, we removed the old combi gauge, revealing a bird's nest of wiring.

Patrick also marked the light bulbs individually, to assist in returning them to their correct positions within the gauge. It wouldn't do to have the choke light illuminating in the oil pressure position!

 

After pulling the old sender and cutting the now-defunct braided wire the new sender was installed and the new electrical wire was run through the firewall.

Patrick wrapped the new wire in cloth tape to give it a period-correct look. 

It was nice to see that the grommet in the firewall was intact; my parts book neglects to even show a part number for it.

And then the job is done. The next morning, a wet and humid one, the gauge reads cold. Ha!

Trim Reboot

A well-meaning PO had removed the lower boot trim on the car at some juncture in order to repaint.  Unfortunately he or she didn't understand how soft the metal is, which resulted in some damage.

Nothing earth-shattering, mind you, but still of concern.  Both sides had been bashed in the same way, which lent a certain symmetry to the car but little in the way of correctness.

My lucky day arrived when a package from Germany was deposited at my front door by DHL, who actually delivered it on time and without fuss.

New trim pieces.  Lovely.

Getting the old trim off is quite easy as long as you do it carefully. My yellow plastic all-purpose trim tool works very well.

 

No hammer required, just palm-power.

Once the trim was removed I took the time to notice a couple of paint layers underneath. First was a flat black, which I  have found everywhere on the car. Whether this was a rat-rod paint job or primer to go under the current gold color, I can't say. 

There's even a bit of original Tampico under there!

I replaced, on the flange that holds the trim, the clips that had remained in the old piece, fixing them in the same relative positions. 

It was an easy matter to attach the new trim without any special tool by pushing it into place.

Much better.

As always, a new item tends to show more sharply the defects in the original pieces next to it.

For the other side, the process was repeated except that the photo below was shot within the enclosed garage as Seattle s experiencing a November monsoon.

Rear Bumper Reloaded

This should have been easy. The rear bumper used to look like this.

Now it looks like this.

 

All I had to do was find a new center bumper piece.  Which I did, as the photo illustrates. 

But to get the old bumper removed and ready for re-installation was not so simple a task. First, the bumper had to be removed.  What was required was to cut the bolt that held the d/s bumper horn to the quarter panel, as the internal cage nut had frozen as hard as an Antarctic glacier.

The end of the bolt still inserted into the cage nut was then drilled out.

And the cage nut re-tapped.

 Last step was to rust-proof the new rig.

At the end it was necessary to take some time to admire the NOS bumper center,  so old the part number sticker on it only contained seven digits.

Now it was reinstalled, to be admired in contrast to the nearby long-neck differential.

All but the first two photos donated by Patrick O'Neil and Midnight Motorsport, who also did all the work (with the exception of sawing the old bumper horn bolt).

Suspension Bushings and Parking Brake Cables

While renewing the differential and CV boots it seemed like it would be a good idea to replace all the rear suspension bushings. The car definitely was feeling loose toward the stern on Seattle's notoriously well-maintained streets.

The trailing arms and subframe were removed.

Crunchy cracked items prevailed everywhere.

New bushings were lined up like little ducklings behind their mother and installed.

Meanwhile the parking brake cables were swapped. Since I didn't have the correct rubber grommet a small length of hose was stretched over the appropriate area on each cable.

 Sure enough, a day later I located a source for the grommet. As they say in the surfing world, "You should have been here yesterday."

Thanks again to Patrick O'Neil for the photography (with the notable exception of that cable grommet!) and all work performed, live and unexpurgated.

The Differential Equation

According to Wikipedia, "a differential equation is a mathematical equation that relates some function with its derivatives."  That sounds about right.

My rear drive had a number of problems, as did its derivatives, otherwise known as the CV boots.  Briefly, most of the seals in the diff leaked.

As did one of the CV boots, the early clear kind with the differential fluid visible inside.

And so all were removed.

A couple of years ago a fellow enthusiast sold me an NOS diff seal kit. They are still available, but almost certainly not in this cool box:

 We also discovered that the old differential mount - yet another derivative - was fried.

Now it was time to take stuff apart.

The inside of the differential looked nice.

The hour arrived to reassemble everything. A special tool was made to aid with installing new CV boots. No heat required to get them back on with this little number.

I was worried that the diff mount might be NLA but no, they even use this version on the E12!  I was also concerned that the metal above this mount would be compromised by rust - this seems to be fairly common with NKs - but my rear structure was still solid after 49 years.

 The differential and CV boots are installed again.

And all is well with the world.

Special thanks to Patrick O'Neil for the work, and for the photography!