Front suspension renew and adjustment

[Zed Head]

43 minutes ago, Zed Head said:

Take a picture from the side and post it.

Oops, I didn't scroll up far enough.

You can reach the suspension bolts from the side when the car is on the ground.  Loosen them up a bit and roll the car back and forth.  No danger if the car isn't being driven.

Your front end is way up there though.  That's probably why your wheels are carked.

[Zed Head]

Here's a 72 image from Hagerty.

https://www.hagerty.com/articles-videos/articles/2018/09/20/datsun-240z-values-show-appreciation

[Terrapin Z]

2 hours ago, BDJeff said:

OK, here's how I set the suspension when I tighten the lower control arm bolt.  Minus the two people sitting in the seats.  You can see the gap between the jack stand and the sub-frame.

 

That is a lot of angle on the front arm, like the struts are not moving or the springs are to heavy.  Did you remove all 4 when you changed the struts? Like ZH said maybe mixed the front and rear springs? Also are the Tokico's set on #1 dampening?

 

[BDJeff]

I didn't do the rear suspension so there's zero chance of mixing springs.  Yes, the struts are on the #1 (soft) setting.  Good ideas about removing the sway bars and see what happens.  I'm also going to try resetting the control arm bolt while it's on the ground in the driveway.  Although I find it hard to imagine the rubber bushings in the control arm mount holding up the car but I've seen stranger things.

Thanks for the input.

Edited June 7, 2019 by BDJeff

[Zed Head]

This bushing has a long side and a short side.  Maybe installing backward can cause things to bind up.  If so, you can just swap arms, no need to swap bushings.

[BDJeff]

Yes, another good suggestion but I checked this about a half dozen times before I re-assembled the rest of the suspension.  The long part is towards the rear on my car.

I separately released the sway bar and drove out to the street and back but no improvement.  I then loosened the control arm bolts and drove out into the street and back, again with no improvement. 

So this weekend I'm going to disassemble the top of the strut assembly and see if I can compare the old strut with the new (correct, I double checked the P/N) strut.  Also will check the assembly of the upper bearing.  For some reason I thought the strut mounting insulator and strut mounting bearing may not be seated correctly.  And these are the same springs that came out, I never worked on the rear suspension

[Terrapin Z]

Wow, that is a head scratcher. It sure seems like the strut is not moving down with the weight. If you push the car down, it does move the suspension down right? not super stiff, or no movement?

Everything looks right, so I would have to go back to the item that was replaced. If you do pull the strut back out of the tube confirm the BZ number on the strut housing itself. I am running out of ideas here.

I put Illumina's in my car FR and RR and it sat really low. I was using their springs though, which the fronts collapsed on me. I recently put heavier springs in and it raised the car but not nearly as much as yours. 

[Zed Head]

If you can remove the spring and run the strut through its travel you'll know if it's binding or not.  It does seem like your spring is incorrectly seated though.  The bearing sits in a pocket, if it wasn't seated properly it would move the spring seat downward relative to the body mounting point.  Good luck.

[BDJeff]

OK, so this is making me crazy.  I fully expected to take it apart and find something amiss but it appears all is well.  The spring ends are in their registers, the bearing is seated in the upper bushing and matches the load point at the top of the spring mount.  And the struts are the same length.  The only difference is the old strut sags back into itself but the new strut pushes out the whole length but the extended length is limited by the strut length.  And the strut capture nut is fully screwed down so that's not off either.

 

[BDJeff]

Found it!  They sent me the wrong strut in the right box.  Stand by

[BDJeff]

This is becoming a real saga, sorry!  In the previous episode, you can see the two struts looked very similar but I was comparing the old one to the new one while it was still in the strut housing.  I finally took the new strut out of the housing and compared them side by side on the bench!  And look!  They're different, further investigation shows I got a different shock than what was listed on the box.  It's just long enough to make a difference.  Is this a rear strut?  It's a BZ3038 where the box shows it as a BZ3015.

 

Just found it, looks like what I have is for a 280Z front.

 

 

Edited June 8, 2019 by BDJeff
New info

[Zed Head]

BZ3038 is the base shock, the others are renumbered based on the gland nut or the space underneath.  They're the same shock just different part numbers based on the accessories.  I have some of the basic Tokicos in the garage with both labels.  I can peel one off and 3038 is underneath.

Your problem would be with how long the shock is when compressed.  The strut is not settling under the weight of the car.  Have you run them through the travel?   Maybe they're binding up.  You should be able to fully compress the shock by hand.