Replacement Throttle Body Linkage Return Spring

[Captain Obvious]

On 7/22/2023 at 7:30 AM, Terrapin Z said:

after putting my sunglasses on to cut the glare it looks to me like the washers and center collar pin are the same but the long spring might be a different length.

Haha! Yeah, sorry for the glare. Those parts are too nice for my car. That's why they're in a box.  Haha! 

[HusseinHolland]

So, question - has anyone determined a suitable generic replacement for the earlier (75) style external return spring? I'm looking online & of course can buy a generic set off Amazon or from Harbor Freight, I just want to make sure I get something that will be a suitable weight.

 

I cleaned mine up when I did the TB cleaning, but the tension isn't enough - I often find the throttle not closing properly during light throttle (low speed, in town) situations

 

TIA

Edited April 16 by HusseinHolland

[Yarb]

@Terrapin Z

[Terrapin Z]

8 hours ago, Yarb said:

@Terrapin Z

Thanks for the notification. It sounds like HH is looking for a generic replacement spring. 

I may still have some stock ones but they would of course be used. 

[HusseinHolland]

On 4/16/2024 at 5:50 PM, Terrapin Z said:

Thanks for the notification. It sounds like HH is looking for a generic replacement spring. 

I may still have some stock ones but they would of course be used. 

I need to find a replacement that has better tension than mine - if you have used ones that are not rusted & weak, I'd love to buy one from you. I have not found anything generic that has similar tension at all....

[Terrapin Z]

I still have the one circled in green, The other one was sold further back in this thread. 

It is dirty but still feels strong, I have a 240Z so I use different springs. 

Edited May 15 by Terrapin Z
Added the pic.

[HusseinHolland]

On 5/14/2024 at 9:58 PM, Terrapin Z said:

I still have the one circled in green, The other one was sold further back in this thread. 

It is dirty but still feels strong, I have a 240Z so I use different springs. 

 

Understood. Mine looks the same as the heavier one on the right, so I don't think I want to put a lighter weight spring in its place.

[HusseinHolland]

@Terrapin Z @Captain Obvious - did either of you measure the wire diameter & length of the 280Z spring by chance? It would save me another fiddly removal to do so myself - of course I should have done that when I took it out the other day to test fit a generic spring, but I didn't 🤪

[Terrapin Z]

2.83" long outside to outside

.05" diameter

 

[HusseinHolland]

1 hour ago, Terrapin Z said:

2.83" long outside to outside

.05" diameter

 

Many thanks ! Closest I could find is ..047x2.76", .39 OD. I'll give that a try 

[HusseinHolland]

OK - so the generic spring I got off Amazon works, and is not excessive tension, nor too difficult to install in place. We'll see how long it lasts.

Since links don't last particularly long dimensions to look for are:  0.047"x0.39"x2.76" - "Stainless Steel Tension Spring Wire" or 'Extended Tension Spring Wire"

comparison:

 

[EuroDat]

On 5/15/2024 at 3:58 AM, Terrapin Z said:

I still have the one circled in green, The other one was sold further back in this thread. 

It is dirty but still feels strong, I have a 240Z so I use different springs. 

Btw: If the wire diameter, spring diameter and materials are the same, the spring with the less coils (green circle) will be a lot stronger, but will have less travel. Based on the law of Hooke.

Hookes law: F = kx (F is force, k is spring constant and x is distance travelled.)

Wire diameter: When the wire diameter increases, the spring constant also increases. A thicker wire ensures that the spring constant becomes stronger and is even more difficult to deflect.

Spring diameter: An increase in the spring diameter will lead to a decrease in the spring constant.

Number of turns in the spring: The higher the number of turns, the lower the spring constant.

 

It would have been interesting to test the springs with a weight to determine the k factors.

Edited May 21 by EuroDat