This is kinda hard to explain and I searched but it's hard to know what to search for because I am not sure what is causing the problem.

The issue is that sometimes the whole transmission (shifter, housing, t-case, and all) will rotate clockwise (toward the passenger) about 10 or 15 degrees which will cause the engine to race somewhat. The trans mount seems to be in good shape, no cracks in the rubber.

 

The trans probably is ok, but may still allow it to rotate that much if the motor mounts are shot. On my '83 when I got it the rubber was completely torn through on the driver side motor mount, the trans mount and pass side mount were in ok shape, but the engine still kinda flopped around alot.

Also sounds like your throttle cable isn't exactly mounted properly. It should be flexible and in some cable housing from the body to the bracket on the intake, then the cable is no longer housed as it goes to the throttle linkage on the carb. There should be no different movement between the intake manifold and the carb, though.

 

I replaced The passenger side motor mount when I bought it and the driver side looks new and has no cracks in it.

Good point on the throttle cable. I'll make sure I get that adjusted. I put a weber on last month.

 

The rubber could still be torn away from the metal of the motor mount. "Looks" new doesn't mean it is.

 

I'll get a jack under there to find out, but I highly doubt that is the problem. When I replaced the other a month or so ago, it was in good shape - no breaks.

 

I would look at it this way.. If the tranny is moving, then the motor is too. The are directly connected. I would definitely take another look at that mount.

 

That is exactly what happened to my transmission when my drivers side motor mount had separated.

I know you checked it, but I'll bet it's broken.

 

Didn't have time today to check but I will check again as what you are saying makes sense.

 

My Supra did this too when the motor mount separated.

 

You guys were right! Thanks for insisting on that.

 

yea defintly was a motor mount problem after youget the new one in chain them so they cant flex as much and you wont have that problem

 

Great! Nice easy, cheap fix.

I know that I couldn't tell mine had broken until I actually took it out. It was a nice clean separation right where the rubber attaches to the metal, right where you can't see