Hello all, I am the original owner of a 1972 240Z. I am trying to refurbish my baby and have run into a problem I can't figure out. I had extensive body work done and the engine rebuilt. When I put the engine back in, the throttle shaft from the intake manifold to the firewall bracket does not line up. I used both new engine mounts and the old mounts and the shaft has the same displacement. I put a new transmission bushing in. I thought the tranny might be the problem but in order to lower the back of the engine enough to get the throttle shaft to line up the transmission lays down on the crossmember with no room for any bushing. I have rebuilt the intake manifold and thought I got it together correctly. Any thoughts? What did I do wrong here?

"What did I do wrong here"?

Ran the wrong carbs...... Nyuck nyuck

Run the right carbs and linkage and that pivot will work fine. Other than that I don't know what to tell you.

Harry, That looks a lot like the old '73 linkage and balance tube. The conversion works better with the intake manifolds, balance tube, and linkage from an earlier car. You are welcome to come check out my '73 w/ Z Therapy carbs to see what it looks like. I'm in Fort Collins. Send me a pm w/ email.

Cheers, Mike

I have the original carbs as well as a set of Webers. Both fit on the manifold and use the same throttle shaft. I have the Webers cleaned and ready to go back on. The SUs are still in a box ready for someone with a more classic mentality to put them back on. Before the engine was rebuilt I had the webers on there and the shaft fit just fine.

Check the old motor mounts and see if they are the same as the new ones. Also make sure they are on the correct sides. I believe the left and right are different sizes.

-Mike

I have a set of roundtops on my 73. I'm in Berthoud and could stop by sometime to compare. Send me a pm if you want.

Harry,

Can't say why that shaft doesn't fit now but will tell you that SUs do not run that shaft setup. The SU linkage has a big loosy goosy joint between the balance tube and the pivot on the firewall that will absorb a lot of engine twist without binding and can make that run from the balance tube to where ever the pivot ends up on the firewall. Oh and that's where the pivot needs to be to keep the angularity and distances right from the pivot to the gas pedal.

sounds like a small gathering is possible this weekend.

ken, mike, harry, ncolz(glen), me, and anyone else wants to make it. Who wants to host? ;-) BYOZ.

The motor brackets look to be on the correct side.

Edited March 22, 201114 yr by Darrel

Here's a set with the correct(?) linkage and the joint Bruce is talking about.

http://www.zcar.com/custom/images/phorum/7545_SuCarbuerator001.jpg

Thanks for all the help. I modified the linkage back in '91 to get the Webers to work. As I remember all I did was run the shaft straight back to the mounting bushing on the firewall and then I used the arms that were on the SU shaft to hook up to the Weber throttle linkage. Maybe there was enough play when things were old and the transmittion mount was worn out. Now with the new tranny bushing there isn't. I thought about the engine mounts. The rt and lt brackets that bolt on the engine then bolt to the rubberized mounts are different on each sode. If I were to switch them they would put the engine in a tilt to the left instead of the slight tilt to the right. Also the brackets arre the same as the pictures in my 1972 repair manual. The old mounts and the new mounts are exacltly the same. The intake manifold is the original '72 part that came with the car. Looks like I need to explore a new throttle shaft setup. Thanks for the help so far. More to come when I do some more tinkering. OR I could go back to the original SUs - just a thought. (The webers gave me more power however)

Harry, assuming there are no clearance issues with the hood, it looks like you could weld a 3/4" extension onto the bottom of the firewall bracket, then drill holes in the extension and put the bolts through it. That would enable you to raise the pivot hole up the 3/4" or so that you need to capture the shaft.

Lokar Throttle Cable Kit - I'm getting ready to purchase one as well..........Harry, by the way - great to have you on the forum. Original owner!!

http://www.racingonthecheap.com/throttle-linkage-vs-throttle-cable/

Edited March 22, 201114 yr by Travel'n Man