Suspension Refresh - 1970

[JonnyRock]

So I just pulled the Z out of her Winter storage spot in the garage and fired her up. With my dad's help, we got her running better than she ever has. From when I purchased her in October of 2007, until October of 2010 she was my DD @ college. She did right by me through those years and now that she's no longer on DD duty, it's time a do right by her.

First thing up is a suspension refresh. There's roughly 75k miles on her over these 42 years and I'm pretty sure all of these bushings are original. I'll be doing this piecemeal because the wife is still in school and my funds are limited. But this rubber needs to be replaced. And it's getting replaced with rubber, as I prefer it over the harshness of poly.

Endlinks look REAL rough.

As do the T/C bushings. These will be replaced with a ball in socket kit.

And the whole front assemblies will get cleaned up (maybe pc'd or POR'd) as well. You can see there's a lot of grime on there.

And I assume I'll be doing a ball joint and steering knuckle swap because this is an early car.

I'll have to start after the Datsun Driving Canby Fun meet on June 9th!

[Arne]

Jon, I seem to recall that early (small-shaft) ball joints were available again. Search around a bit before you buy later knuckles.

[JonnyRock]

Thanks Arne,

MSA still only lists the later ones, but RockAuto lists 11mm and 14mm. Am I correct in assuming 11mm is what I'm looking for? The Moog 14mm say "from 10/69 on"...

[240260280z]

Looks like you have the ball and socket TC rod kit installed already; so just get a new delrin insert and a rubber bushing for the back.

For the end links, I would get the polyurethane type. They do not contribute to roughness of ride however they make your car turn much nicer.

[JonnyRock]

Looks like you have the ball and socket TC rod kit installed already; so just get a new delrin insert and a rubber bushing for the back.

For the end links, I would get the polyurethane type. They do not contribute to roughness of ride however they make your car turn much nicer.

Does MSA sell just the insert and bushing? If poly won't really increase harshness in that location, then I'll go with it. RockAuto has some pretty inexpensive poly end links.

And do you know the correct size ball joint?

[JonnyRock]

So I started pulling it all apart last night. Nothing was too stuck or corroded luckily.

My tie rod boots are TOAST, check it out:

That cotter pin was a little PITA too, snapped the tips off of my needle nose pliers.

Got most of it apart in about half an hour last night, and will finish up tonight. Then I'll bring the smaller pieces to work to sandblast, pop out the old bushings, seal and POR them. Then replace and install.

I've been following the great walkthroughs at Atlantic Z Car Club

[240260280z]

A good scrub with a plastic or soft brass wire brush to clean off the dirt from the threads, holes, margins and surfaces before removing any part is a good practise.

It will also allow a penetrating spray to easily reach the margins rather than be blocked or absorbed. Don't go too aggressively and brush off the plating.

Clean surfaces also allow tools to connect properly without marring/slipping.

Clean threads are an absolute must when removing tapered thread nuts.

For cotter pins, try to get the two sides parallel and wrinkle free like a new pin, then push through only a wee bit, you can then stick an object through the round hole at the other end and pry it out.

[JonnyRock]

A good scrub with a plastic or soft brass wire brush to clean off the dirt from the threads, holes, margins and surfaces before removing any part is a good practise.

It will also allow a penetrating spray to easily reach the margins rather than be blocked or absorbed. Don't go too aggressively and brush off the plating.

Clean surfaces also allow tools to connect properly without marring/slipping.

Clean threads are an absolute must when removing tapered thread nuts.

For cotter pins, try to get the two sides parallel and wrinkle free like a new pin, then push through only a wee bit, you can then stick an object through the round hole at the other end and pry it out.

All good points. I used a wire brush, but had misplaced my PBlaster so decided to try disassembly anyway. It went pretty smoothly.

And as far as the cotter pin, that's exactly what I did. It really wasn't too difficult to get out, I was just very surprised that it broke my pliers! Luckily they're lifetime warranty.

I'll be bead blasting many of the components after I pull them, then getting the old bushings out, seal, paint, re-install.

Now that I see my tie rod boots are toast, I'd like to replace them. But it appears one of them is NLA. I'll do some more searching, but what is my best option?

[Zed Head]

The items you've showed in your pictures won't really be affected by using polyurethane over rubber. Have you experienced a car with polyurethane bushings or are you just going off accounts from the internet? Different suspension and drivetrain mounting points will be affected differently by the type of material. A blanket "polyurethane is harsh" statement doesn't mean much.

[JonnyRock]

The items you've showed in your pictures won't really be affected by using polyurethane over rubber. Have you experienced a car with polyurethane bushings or are you just going off accounts from the internet? Different suspension and drivetrain mounting points will be affected differently by the type of material. A blanket "polyurethane is harsh" statement doesn't mean much.

In general, polyurethane is utilized to provide a more firm ride. Combined with other factors (springs, tire sidewall, etc) they become a component of a harsh ride. They also tend to squeak. Yes, these are generalities.

I decided to go with the rubber (except the endlinks), and it's all purchased. Should be here tomorrow. I hope to do a more complete refresh of the entire vehicle at a later date and who knows, I may go all poly then. We'll see.

[JonnyRock]

Got it all off of the car. The tie rod ends and ball joints are pretty well stuck in the steering knuckle. Not a whole lot of luck with a mallet or pickle forks. I did manage to get one tie rod end out of the knuckle, now everything else is soaking in degreaser. And the arms are soaking in the parts washer. If I can get everything apart tonight, I'll be blasting it tomorrow!

[Zedyone_kenobi]

Good Luck Jon,

I just finished this EXACT project. My advice is clean all the threads thoroughly, and REPLACE the bolts that hold on the ball joints. The torque spec on this is 35 - 45 ft lbs if I read my FSM right. I snapped off two of my bolts. I went out and bought some new zinc plated bolts that were grade 8 or better.

Also, do not forget to grease the ball joints and tie rod ends. If you get into any binds please just ask. Also make sure your transverse links are in good shape. One of mine was slightly bent.