After reading and doing some searching I believe the solution to a vibration problem I have is to fix/replace my transmission mount(s). My driveshaft and u-joints seems to not have too much play, so for now I think my problem is with the mounts. (if I am wrong, then I will move to the U-Joints)

Going via my Hyanes manual I pryed the tranny against the transmission crossmember (highlighted in red) There was a significant amount of play here. I could have easily gotten 3/4 of an inch play up and down at least so this makes me believe there is a problem.

I have attached 4 images, color coded as follows:

Red: Transmission cross member

Blue: Seems to be a cylindrical rubber mount to me, but it looks like it is missing the rubber, since I have seen no other mounts in my life, I may be wrong. The Orange arrows point to what I am talking about in regards to missing rubber.

Green: There are 2 cube mounts that look to be in at least OK condition. I think these may be the two mounting pieces mazdatrix has as part number 39-340A-FB01


Is the "blue" mount bad? It seems to be to my eyes. Can I buy just the rubber part? Is so where?


Any help is appreciated.

 

Another View

 

The Part in question:

 

Opps.

 

This one is pretty blurry, but it shows the other 2 "green" rubber mounts that seem to be in OK condition.

Also, I failed to mention, the RX-7 in question is a 86 N/A MT

 

it looks like it moves around a bit i say replace it

 

I've been putting fixing your exact problem on my TII for waay to long. You get any noise going over bumps?

 

my shifter bounces up and down over bumps, about 3/4 to an inch. Does that mean my tranny mounts are shot? i know my motor mounts are almost gone.

1990 vert still N/a but streetported and 5 speed.

 

TTT

Check out the FSM tranny section near the end, about 4-5 pages from the end. It "looks" like there's one there. I'm going to call up the parts dept at a local dealership today.

 

The "green" mounts, block on the side, are sagging allowing the center of the trans to sit lower and expose the shank on the center bolt (orange arrows). Odds are ridding around like that has done damage to the center mount as well.

The side blocks support the trans up and down.

I believe this was explained to me by mazdatrix. If you look at the parts it makes sense. I replaced all of them on mine.

 

You dont replace the center piece. You have to buy the bracket which contains the rubber part pressed in it, and two rubber isolators (side pieces). The center part your showing is where the pressed rubber part in the bracket has separated. Mazdaformance sold me the bracket ($46) and two isolators ($17 ea). Makes a huuuuuuge improvement to the vibration.

Jim D

 

yes that needs to be replaced

 

ya, mine is like that too. i don't remember the blocks sagging but they must be cause the center piece hangs low on mine too.

 

Thanks everyone. My question has been answered. I just didn't realize that the center "blue" mount was part of the crossmember. I have ordered the parts and await there arrival

I will let you all know if this helps my vibration problem (I think it will).

 

If anyone is interested:

Purchased:
39-370D-FB01 (bracket with center rubber piece)
and
39-340A-FB01 (2)

From Mazdatrix. Installed. NO MORE VIBRATION Problems.

To sum up (for easy searching down the road)
86 N/A w/Manual Transmission

Vibration at different RPM's, much less when clutch is to the floor.

Checked U-Joints (while still on car) Seemed to be tight.
Checked Transmission mount with a pry bar. Very loose.

If fact it turns out that the rubber in the center had totally worn out and detached from the metal chassis.

Replaced with parts list above (the Bracket, and the two other mounts)

Everything is good.

Now on to more projects...
Thanks for the help everyone.

 

ha! i just swapped everything myself as well, If i'd seen this sooner then I'd helped you, but everyone beat me to it. good work