Throttle Actuator Shaft Stripped...

[901M3]

I was in the process of replacing the gears in my throttle actuator and the threads of the shaft stripped. Do you guys know of anyone who would sell the shaft only or do I need to replace the whole actuator()?

[Amirsm3]

You may be able to pick up a used one. I remember seeing busted actuators in the for sale sub forum. You don't need the gears, just the shaft, right? So I'd hunt for someone with a broken one in their garage and buy it off them for cheap

[901M3]

Good idea thanks.

[TWiTCHY]

Could you tell us how that happened so the rest of us here don't do the same?

[pbonsalb]

He overtightened the nut. Buy a broken actuator to salvage the shaft, or to start the mechanical rebuild process over on. The electronic rebuild is another matter.

[JDM_CL9]

You can get a thread repair tool too and try that before shelling out for a used TA.

[JonM]

Those threads are easy to strip and the trickiest part of this service. As others said, you need a replacement, from a bad actuator. I tried to re-cut the threads and was unsuccessful.

One defense for the future: Heat up the bushing (bake in over or soak in boiling water) before you attempt reassembly. This will reduce the stress on the threads. And, make sure you have the sequence right: put the two 1/2" washers on first, then the output arm (squared off hold cut in it). Not the other way around. The washers may have a slightly larger ID than the OD of the shaft. This lets them wander around a little, which is NOT ok. They need to be as perfectly concentric (e.g.: lined up) with one another as possible. If the edge of the lowermost washer clips the edge of the bushing, torque will go way up, you will think you need to tighten more, and you will strip the threads.

[kb9uwu]

has anyone actually fixed a TA by replacing the gears?

[drrust]

I encountered the same situation. I was able to salvage the shaft. One has to press on the ring in an alternative fashion. I used a 6" C-clamp, some plastic blocks, and a 3/8" drive socket. A very messy diagram is shown (not much of an artist). Once pressed on, I had enough thread to secure the lever and two washers. I used Loctite so as not to over torque.

I did the gear replacement as a PM and did not have any codes. Both actuators are working. Not sure how successful repairs are when codes are thrown

[drummer20]

I read a guy on the m5 boards salvaged an actuator that threw a code with brass and delrin gears only....still going strong two years later