[Solved] Help with suspension needed

[Villeman]

Hey guys, 

 

sooooo…  if have a problem with my suspension. I swapped to a full poly setup and first mistake, we didnt loosen and retighten the bolts once the chassis was in neutral position but we fixed that. BUT:

I was so smart to put Gabriel shocks in AND THEN add oil. I now have the funny problem that pushing the fender down once works fine, twice becomes harder and 3 times makes the suspension hard as a brick. My question is, can I just remove the oil or did I kill the shocks already ? (in that case I would need to order replacements before dismanteling them)

 

Thanks,
Richard 

[jhm]

I can't imagine there being any damage to the shocks after three strokes of compression.  I would remove and refill per the manufacturers directions.

 

Just curious....why pick Gabriel for shocks?  That's not a common choice for the Z, but I hope they work well for your application.

[Villeman]

Hey, 

 

no, I drove it like that for some time (don´t ask...around 700 miles). The Gabriels were available but I think I will go KYB ones for now. 

[jhm]

Are they gas shocks?  If so, they should still hold their gas charge and not be leaking oil, if they're ok.  If not gas-charged, they'll still be leaking oil at the shaft seal and you should be able to visibly see the oil discharge.  If they had blown due to excessive oil or pressure, the seals on the shaft would be leaking (possibly quite a lot).  Is there any visible oil on the shaft or in that area?  If not, good chance that they're still fine. 

 

You'll know for sure when you remove them and refill....they'll feel firm on the compression and extension strokes (moreso during extension). 

[NewZed]

8 hours ago, Villeman said:

BUT:

I was so smart to put Gabriel shocks in AND THEN add oil. I now have the funny problem that pushing the fender down once works fine, twice becomes harder and 3 times makes the suspension hard as a brick.

 

What do you mean by "add oil"?  With the aftermarket shocks the oil serves no purpose besides hindering rust.  The aftermarket shock shaft and shock internals don't even "know" that there is any oil in the strut tube, if that's the oil that you're talking about.  

 

Seems like you might be assuming the wrong cause of your problem.

[NewZed]

8 hours ago, Villeman said:

I now have the funny problem that pushing the fender down once works fine, twice becomes harder and 3 times makes the suspension hard as a brick.

 

And, this "test" is meaningless.  I have KYB's on my car and the car doesn't move if I push on a fender or even stand on the bumper.  But it rides just fine.  The cars are designed to have firm suspension.  You might have had some air in the wrong place in the shocks that needs to be worked out and that's why it moved a few times before firming up.  Working the shocks before installing is actually in the instructions of most aftermarket shocks, because they tend to sit sideways during shipping.

 

You should just drive it and see how you like it.

[Villeman]

Well, drove the car quite a bit. At this point i am unsure about the source of the problems, true. Thing is, one side can be pushed in when i lean on the fender like I would expect, and I would be fine if it were just stiff. But changing stiffness with repeated compression is strange. 

 

True on the gas shocks not knowing their surrounding. I stil assume that filling in oil (mistake, instructions read later stated: NEVER FILL THE OUTER CASING WITH OIL). Just wanting to be sure since I would have to order shocks from the states or potentially block our lift for a month.

[jhm]

As NewZed pointed out, the reason one puts a little oil inside the strut tube is to prevent corrosion and assist with heat dissipation when the shock body heats up during heavy use.  I've been doing this for years with all brands of shocks, both gas-charged and non-gas, and have never had a problem.  You really only need a little to do the job -- enough to cover roughly the lower half of the shock body once inserted into the strut tube is what I shoot for.

[NewZed]

9 hours ago, Villeman said:

Well, drove the car quite a bit. At this point i am unsure about the source of the problems, true. Thing is, one side can be pushed in when i lean on the fender like I would expect, and I would be fine if it were just stiff. But changing stiffness with repeated compression is strange. 

 

If it happens consistently, after driving, it might be that the shocks are damaged.  Are they "old stock"? 

 

Also, as I mentioned, some shock instructions ask you to run them through their full travel before installing, to get the air and the oil in the proper places, inside the shock.  I can't find anything on the internet but I just installed some KYB's on a truck and that's what they said to do, on the paper instructions that came with them.  Maybe your Gabriels have some air pockets.  Drive over some speed bumps, maybe, get the oil flowing inside them.

 

My KYB's are firm from the start, even after sitting in the garage for months,  so what you're describing does sound wrong.  Especially if it's on just on side.

 

 

[Villeman]

Yes, they are old stock... guess I will order KYB for peace of mind

thanks everybody!

[Villeman]

So, KYB delivered to Germany in 2 Days (Rockauto+Fedex)    Just thinking, how can I check whether I have mixed up the springs? 76 280z 2+2  …...just want to be SURE this time !

 

 

[NewZed]

You have a 260Z 2+2 with stock springs?  

 

That's a good question.  The FSM shows that they all have the same spring constant but the left side front spring is shorter than the other three. I don't know why that would be, since the driver is on the left in America.  Maybe they are Japan specs.

 

I would look through the FSM and see what you can figure out.  Certainly possible to get the short spring in the wrong spot.

 

 

 

[NewZed]

Actually, I'm not even sure those are 2+2 specs.  Dilemma.

[Villeman]

280z 2+2    and I think for the front suspension there should be no difference

 

[Villeman]

So, a quick update: Apparently all shocks seized completely. Since seizing for air shocks is unknown to me, I assume the Oil in the strut casing did this (filled to the top) so thats definitely something to know! 

 

Thanks everybody for the help. New shocks are in and rides like a charm

[HuD 91gt]

even with the old style struts, weren’t you only supposed to fill the bottom with an inch or two of oil?

 

glad to hear you found the issue though.

[NewZed]

Sounds more like they were just bad shocks/inserts from the beginning, or they were actually the wrong ones for the car.  

 

The oil in the strut tube would have had no effect.  It's on the outside of the shock body.  It doesn't move at all as the suspension moves.  Just a pool of oil, sitting there, doing nothing.

 

KYB makes a good product.  Good luck.

[Villeman]

yes, but once they break containment..... and if there is oil and not air surrounding the broken seal. They were okay when I got them and a year later you cant move them one inch. Still, yes, success!