2nd gear shifter wobble/shake

[Jmoyet]

3 hours ago, Zed Head said:

Maybe monkey motion refers to what happens to the shifter in second gear.  Never did understand why they called it that.

Yeah quick google confirms its the type of shifter to transmission setup which is what I have on the Z

[EuroDat]

You have an F4W71A which is the original series 1 transmission. The selector can wear just like the F4W71B and FS5W71B, but the components aee a little different. That free movement you are feeling is what is making the chatter sound in second gear.

The problem you are experiencing is an accumulation of wear allowing things to more out of harnomy of each other and increacing frequency magnitude etc. This is a similar problem Nissan had with the 280Z and to cure it they bolted a huge block of metal to the diff mount cross member.

Your transmision has wear and that is now showing in second gear under load at certain revs (frequencies).

I would try to replace all the bushings and the two rubber cones in the selector. I'm not sure if that are available. Reduce the free play and it wil most probably cure your rattle. Have you tried removing the gear knob. That changes the momentum of the gear stick and can confirm that selector free play is a cause.

 

 

What does the codering mean.pdf

[EuroDat]

Have you tried changing the oil in the transmission. A member on this forum "Chickenman" recommends an oil from AC Delco or GM. The part numbers are AC DELCO USA part number is: 88900399. GM USA part number is: 12377916. I can not order the GM or AC delco oil here so I have no experience with it. I'm using Redline MT. Here is a thread on the oil subject. 

Another thing you can try is increasing the pressure on the detent springs. There are three in the Adapter plate, but the one you need to look at is the 1st, 2nd selector detent spring. You can increase the tension by adding washers behind the spring. It's easy to do with the transmission in the car. This thread discusses the detents springs. His transmission was popping out of 3rd gear, but if the detents are loose they allow movement and transfer that movement to the selector stick.

They are all simple things to do and you can do it with the transmission still in the car and relatively low expense. I would try them before pulling the transmission out for a full rebuild.

[Jmoyet]

The transmission is the only thing I haven't changed the fluid on I'll give that a go on my next day off. 

19 hours ago, EuroDat said:

That free movement you are feeling is what is making the chatter sound in second gear.

There's no chatter sound coming from it. Just while in gear under acceleration it moves up and down really fast.

[Jmoyet]

My iPhones camera stabilization is making it seem like there is less movement than what there actually is. In reality it moves a lot more about an inch more up and down.

 

https://www.dropbox.com/s/5od3z6b7icirmwy/2016-05-06%2017.05.42.mov?dl=0 

Edited May 7, 2016 by Jmoyet

[psdenno]

A side view video might have been a bit more informative.  Quite a lot of movement in your top view video.  I see why you're concerned.

Dennis

[Jmoyet]

I need to get an app to disable the stabilizer on my iphone to see the actual amount of wobble/shake

[Zed Head]

Here's a though, and a question - when the shift lever is moving in to second gear does it move up or down?  could be that the internals of the transmission are moving, causing the shift lever to move.  In other words, the coupling sleeve is moving back and forth on the synchroniser hub for some reason.  

If only second gear does it, and none of the others, then it's not likely to have anything to do with the mounts.  It would do it in all gears if that was the case.  Could be that you're seeing the first signs of a future failure.

Along the same lines as post #15 - can you stop the movement with your hand?  If you can hold it where it should be then it could just be a detent problem.  But if you can't then it's probably something significant forcing the coupling sleeve to move.  The shift forks sit in a groove in the coupling sleeve.  The sleeve would move the fork, which would move the rod and lever.

[Jmoyet]

Yes I can stop it with my hands with some vibrations still happening. I've yet to change the oil on it might be something I'll be doing tomorrow on it. It's pretty much the only thing I haven't changed the fluids on. Hopefully it's not a failure in the making. If so I've been thinking about a 5 speed but still not sure if I wanna dump the originality of the series 1 240z.

[Patcon]

If you decide to go 5 speed, it is easy enough to reverse if someone wants true originality...I wouldn't run anything but a 5 spd in todays traffic if it's up to me...

[Zed Head]

Try running through the gears under acceleration keeping your hand firmly on the lever.  See if all of the gears feel the same or if 2nd feels different.