How To Repair a Broken Speedo Drive Attachment?

another one

J.B. Weld does wonders for these types of issues. You may be able to use that stuff to put a new nut over the hole. Hard to tell without personally being there.

A competent welder can repair this.

Freddie, the gearbox is cast aluminum and can be TIG-welded by someone in your area. The bad news is, you must remove the whole transaxle (it weighs 155 lbs), drain it of lube that will otherwise catch fire, and take it to a welder; TIG or heliarc welders are not portable.
Once the case is rewelded, the bolt hole probably will need to be surfaced and rethreaded, so maybe a machinest should also be consulted. I would try 'JB-Weld'- an economical aluminum/epoxy material first, as JT suggested.
You have damaged possibly THE most expensive single part of your car. A completely rebuilt ZF dash-2 transaxle, using all-new parts from RBT Transmissions in the Los Angeles area of the U.S. www.rbttrans.com, will cost roughly $10,000 USD. And you pay shipping both ways. Used assemblies of unknown quality cost $5500-up. Which is why I suggest a welder and machinest local to your area be contacted, or try the epoxy.
RBT is the owner of this design of ZF, having bought the rights, tooling and all spares from the German company some 30 years ago. There are no other sources of new parts, although good used parts can sometimes be found. Good luck.

Harbor Freight and a few other sources sell aluminum welding rods that the do it yourself mechanic can use with a map gas torch like a plumber uses to solder copper water lines. There are videos on YouTube to show how to do it. I used it to fix leaks in a aluminum boat. I still think the JB-weld epoxy is the safer way to go due to the threat of the residual trans fluid catching on fire? Good luck, Louie

Guys Wait a minute. Lousbby has another issue to think about. The bolt that broke off is the one that holds the spedo drive mechanism from falling into the trans if one should take off the angle drive. Am I correct? If that sucker falls in you may need to disassemble the trans to get it out. Be warned.

Actually Freddie is the one with the trans bolt issue. Lousbby (Louie) just mentioned JB Weld epoxy or the Alumaweld rods from Harbor Freight may be useful to remedy the problem.

can't you drill/rethread it a size bigger and have a stainless steel insert ? Those pieces with thread in&out side ? perhaps with some Loctide secure the piece in the gearbox so you can carefully have the bolt again in place ??

thanks guys
Here is a lot of good advice but realize that I need to take out the gearbox: (anyone have a thread for how to do it step by step?, and it is correctly this bolt holding gears to spidometere: (this fell in the gearbox but I managed to get it up again does anyone have this part lying around? actual shaft gears were damaged and is about to break in two: (

Freddy

OK- the speedo extension driveshaft is a vital part IF you need the speedometer to work. If not, the little shaft can be safely left completely out and the ZF hole(s) sealed. U.S Pantera vendors have a few good used shafts in stock, and RBT Trasmissions may also have one or two. I can fix most broken speedo angle-drives, but repairing that 4" long shaft is beyond my capabilities.
Locally, you can also try Roland Jaeckel in Germany at (detomaso@gmx.com) or possibly the British or Swedish Pantera clubs for a good used one. They have their own websites. And if you continue to try working on your ZF yourself, I suggrest you purchase a ZF Factory Manual that gives bolt torques, assembly/disassembly procedures and many other such facts. Reprints of the originals are available quite reasonably from all the Pantera organizations in the U.S.

Thanks bosswrench The big problem now is to get out the gearbox and have it welded the part that is broken is probably possible to weld in place but I am a little unsure where I start to take it out. and it's true that it's possible to remove it without removing the engine too??

Indeed it is possible but expect to lose some blood in the effort. Are there any other Pantera owners near you to help? The bellhousing (including two small bolts underneath) must be unbolted from the engine block, the halfshafts separated from the ZF, the clutch hydraulic line undone, and depending on the year of car you have, one or two tranaxle mounts can be unbolted. Disconnect the shift rod at the small aluminum box on the rear of the ZF. There are e-brake clamps underneath that should be unfastened and the AC assembly can be unbolted from the car and folded back out of the way on blankets without disconnecting the lines. The ZF & bellhousing weighs 155 lbs so get a couple of husky friends or an engine crane, slide the assembly back a few inches to disengage the clutch and lift the thing out. It will be slippery from road grunge and oil so be careful not to drop it.
All this is described on Mike Daily's giant website (www.panteraplace.com) Halfshaft bolts & nuts are special so do NOT loose anything! Reassembly is harder (but not impossible) since you must align the clutch input shaft into the clutch & flywheel. Good luck.

Removing the ZF with the engine in place is really not that difficult. One step you may need to do is jack up the rear part of the engine to tilt it slightly so that when the ZF slips rearward it will clear the body and the trans mounts.

I have pulled half a dozen engine/trans combos by my self. It usually takes 5 to 6 hours depending on my level of motivation and the number of rusted bolts. I have never pulled the transmission by itself.
I will be doing one this weekend, and for the first time using a real engine puller instead using a come-along and the center beam of my garage.
It is actually easier than most front engine cars to do.
The key is to jump in with both feet and don't stop until it's out.
Best of luck

Lofoten
Seems I have broken the same part on the trans. This must be a naturally weak area. I have put a vise grip on the speedo gear to keep it from falling but will have to take the trans to have it welded.
Engine and trans out in 6 hours. Broke 3 exhaust bolts in the heads and then decided to cut off the exhaust and heat them with a torch once the engine was out.

obs. sorry to hear that Quickitty. (but everything out after 6 hours not bad I've been trying to get the shaft and the gear out but now it's suddenly not possible to take this up. it is stuck get out only the top part when I loosen the large nut. I may have damaged the shaft when I put in another screw to prevent leakage?
should it not just be pulling this straight up with everything when the screw that I have broken is out?
with great danger that all fall into the box?

thought I'd see if I got everything up before I take out the gearbox. If i can do it, it's the one opportunity to fix this without taking it out. or is it that this sectio in shaft and gear must be mounted with the bottom cap off? anyone have pictures of this and know if it can be installed without falling into the gearbox while in the car?

Freddy,

The speedo gear will fall into the ZF case if you don't put a clamp on it.

In the pic below, #801 is the speedo gear, and #802 is the sleeve (bushing).

John