Monkey of Death

There's a similar thread from 2010 which gave me some ideas, but I was hoping to get some input from the group (please )

Had a local shop that specializes in older cars replace the front struts on my '85 GSL-SE. Installed KYB struts that I got from RX7.com (the shop used the spacers and filled the canisters with ATF per the FSM). Also had them replace all the suspension bushings (Energy Suspension kit), the tie rods and the strut mounting plates. On the way home, the front suspension started knocking. Specifically, the driver side. Not even over big bumps, just rough/uneven pavement (like the street I live on, which makes all my cars rattle). I can actually feel the 'thunking' when my foot is resting on the dead pedal. I took the car back and they've been trying to figure out what's going on (they've tried more spacers, fewer spacers, made sure everything was tight...) I'm hoping to get some input to help them resolve this. They are focused on the struts as the cause. However, one of the things we DIDN'T replace was the idler arm, simply because they aren't available any more. The other thread suggested that could be the culprit. Thoughts? And if it is, what do I do since I can't get that part anymore?

LongDuck

Your stock Idler Arm has bushings that are replaceable and still available. The Moog replacement is the one-and-done solution, but no longer made. Point being, replacement of the Idler Arm bushings should have been done at the same time. The front suspension components you mention have been replaced are not specific to the -SE model, so anyone can chime in here on what they think it might be. In or order of most likely to least likely;

1) They say they installed the top metal ring spacer for the strut insert, but they didn't. This is easy to leave out, and will create harsh knocking on rebound.
2) Strut Top Mount rubber isolator is toast, and/or the strut insert rod is loose, allowing for up/down play.
3) Spring isn't seated in its perch. You would notice this as higher stance on this side. Rotate spring until the bottom coil sits where it belongs.
4) Bump stop isn't installed on strut insert rod, allowing suspension to bottom out.
5) Upper Spring rubber isolator is missing, allowing the spring to rattle within the metal dish.
6) Polymer bushing replacement has resulted in a harsh ride, because polymer doesn't give, while rubber does (OEM).
7) Wheel bearing is damaged or loose, or pre-load is set incorrectly (*if they replaced rotors).

Most of the guys here haven't installed polymer bushings throughout the front suspension unless it's a dedicated track car, because trying to drive it on the street with such hard pivot points makes for a noisy and uncomfortable experience. In fact, it may handle WORSE than with OEM pivots, because the suspension may bind those polupymer busings under certain conditions.

If you've paid a shop to do this for you, you're going to have a hard time getting them to find it and fix it. I'd bet 10min with someone who knows 1st Gen cars would have this nailed down, and as always... we're not there with you to put hands on the car.

Monkey of Death

Thanks for the list! I appreciate the time you spent and it's a big help to start checking things off.
The car is at the shop right now, and they seem pretty determined to figure it out since it started after the repair and they're good guys. Hoping they stick with that determination! In any case, I'll share your list and see if we can get this sorted.
I went back and forth on the poly bushings, and there seemed to be as many people who liked them/didn't notice any difference as there were folks who didn't like them. It also helped that it came as a complete kit/set so I wasn't as likely to forget or overlook something . So far the car is riding much better than before, but I haven't had the chance to put many miles on it yet. And I can't imagine the poly is any harder than the ones that came off, which were the rock hard, 36 year old originals!
Thanks again!

t_g_farrell

iTrader: (1)

I did polys up front, no issues. Sounds like they didn't torque the top bolt down on the driver side strut. If its not tight it will bounce around as the strut moves. Easy to forget to do when buttoning up an install (don't ask how I know). Also make sure the radius rods are tighten to spec and get an alignment (maybe they did that already?)

Monkey of Death

Follow up for anyone curious.
Called the shop yesterday morning to give them the suggestions posted here. They said they thought they'd tracked it down, but to send the list so they could look at it and double check all the work. The knocking was related to the top metal ring spacer (#1 on LongDuck's list!), but they were pretty busy when I picked it up so I didn't get all the specifics. Regardless, the suspension is quiet and she handles like a sports cars again!
Thanks for the help and suggestions! I'm really looking forward to enjoying driving her and (hopefully) taking a break from repairs/restorations for a bit.

LongDuck

Now there's a rare event! Somebody posting back to close the circle on what was found to be the issue!

Nice work getting them on it, and glad you got it figured out. Enjoy!