Reverse switch location

Question:  I am finally reinstalling my back up switch after years of it sitting in the engine bay.  The ZF cover is not threaded and the stock switch (which does work when the lights are on and depressed sufficiently) threads are smaller than the hole.  On the early cars, was there a nut put inside the case to secure the switch along with a nut on the outside to lock it in place?  Any insight would be appreciated.  thanks

As I recall there are 2 nuts to allow for depth adjustment. If the switch is too far in it can prevent the trans from going into reverse.

Is the nut on the inside bonded to the case somehow?  Not sure I see how to adjust it once installed if it is a loose nut?

Seeing these pictures reminds me there were spacers, no nut on the outside. The nut was not attached on the inside.

A previous owner has managed to destroy the OEM mount for the back up switch. The selector housing cover was built with female threads that accepted the male threads on the back up switch. The OEM design had adjusting nuts inside and outside the housing. You might be able to securely mount the switch with nuts and washers despite some idiot having drilled out the OEM threads

Good luck

Larry

Here's a pic of the new style of reverse switch. Notice the Weatherpak connector. This is the switch you now get from the Vendors. I got this one from Wilkinson.

David,

does that replacement switch you just pictured above retain the OEM threads?

Larry

Yes.

thanks guys

Just for information it would seem there are two sizes of OEM thread pattern that are possible to find on the ZF on the reverse switch. One measures in at 10mm and the other at 8mm. The 8mm thread is a finer pitch.

If you are looking for a cost effective replacement for the 10mm, fuelmiser make one , code is CRS110.  This is found for slightly less than half the standard prices charged for a Pantera branded  and is in fact made in Italy.

Fits and works perfectly, and looks exactly like the original switch. Made on the same machine.

Hopefully others will not have to find the ins and outs like I have had to!

Panterapatt- just a little more.

Check the reverse switch hole just isn't slightly larger with threads. It would be easy to miss from above.

APO may have tried to replace it , got the smaller size  and given up when it did not screw in , leaving the smaller switch hanging, causing total confusion for all subsequent owners!!

If it is, just get the 10mm. Should only be around $20.

thanks all,  Will measure and report back.

Percy,

thanks for the substitute switch information. Some quick Google work seems to indicate the CRS110 switch is perhaps common in the land of Oz but not so much here in the states.

it appears the switch is an OEM BMW part and a Google search for BMW back up switch provides many results

Larry

Measured hole - slightly larger than 10 mm.  Switch thread o.d. is exactly 10mm.  Switch falls into hole.  Closely examining hole suggests faint threads still remaining which implies PO drilled out the hole "WHY"??? but it looks very clean and untouched or botched.    I am thinking about JB Welding a thin nut on the inside of the case or just using 2 nuts.  My switch from all appearances is original given the fact I have owned the car 32 years and I found it hanging inside the engine bay.  Are we sure the early cars didn't possibly have a nut on the inside of the cover and the outer one used as the jam nut?

You might contact Ron McCall. He's rebuilt quite a few of these. He would surely know.

Aren’t there lots of easy, cheap ways to fix it properly and permanently? Helicoil, etc.

Easy, cheap is a nut on both sides and am going to try that first considering the fact the cover and switch are both items that rarely get taken off.

Not sure if anyone has pointed this out but if the switch is installed too deep it can actually prevent the ZF from properly engaging reverse gear.

Larry

That’s why the “two nut” solution isn’t the best. You need to be able to adjust the depth of the switch.

Well, to close this thread I started, I successfully installed my original stock switch with an 85 cent jam nut today.  My case shows no signs of ever being threaded.  In fact, the inside of the case has a machined flat area where it was very clear a jam nut had been earlier in the life of the car.  I measured the stack up tolerances to ensure the switch probe was not binding in reverse.  FYI, a stock switch moves 6 mm full stroke with mine reaching continuity at 3mm.  So you have 3 mm of float to play with.  Put a couple small washers on the outside of the case to position the switch correctly on the inside and tighten the jam nut.  FYI the stock switch is a 10mm x 1.0 thread.  While I was in there, I took the liberty to lube the shift mechanism rod and ball with white lithium grease.   Put it back together and reconnected the wires.  FYI the green wire (white and green) is the switched hot when the lights are on.  No backup lights unless the lights are in park or headlight position.  Taking the cover off if I ever have to remove anything is painless so no issues with the nut being on the inside.  cheers and thanks for the input.  

Now to replace all the rear bulbs with new stuff.  Going to clean all the grounds that support the rear lighting as well as sockets, etc.  

If you are considering LED replacement bulbs I can recommend these.

Larry

Did you have to buy the load resistor pack as well for the turn indicators ?

Just checked - can all the bulbs for $79.60. Unfortunately the most basic shipping to the united states of OZ comes in at , wait for it ...... $99.17.  This is killing me.

I am using a new flasher which is compatible with the LED bulbs.

I have an owner in New Zealand wanting a pair of tail lights. Shipping a couple months ago was about 400 but I checked this week and restrictions have just now been removed and a 7 pound package looks to be about $100 now. I suspect your price check may have been finding the restricted pricing that is no longer in place.

was that a price check from the seller or from our USPS website?

I would be happy to purchase the bulbs and ship them from me to you at my cost if that becomes an option for you  

Larry

Just checked the USPS website and these are the current rates for a 1 pound package to Australia

The first class package international has a weight limit of 4 pounds but as you can see is much less than the other option

Hi Larry

I think you are right. The website has not been updated.

These are the options on the Bulb site.

USPS is still not available on the LED merchant options.

I also have the PE flasher unit so don't need ballast resistors.

I will keep an eye on it for a couple of days and hopefully the options will get sorted.