SRB dampers - which way up?

[c64orinoco 667]

My wife is building a SRB Sand Scorcher. We're up to the dampers, and it's already noticable that the SRB dampers seem to be pretty leak-prone.

I have seen the dampers installed upside-down in some pictures - is there any drawback from mounting them like this? Otherwise it seems like the damper oil is just going to drain out over time.

[DeadMeat666 1675]

1 hour ago, c64orinoco said:

My wife is building a SRB Sand Scorcher. We're up to the dampers, and it's already noticable that the SRB dampers seem to be pretty leak-prone.

I have seen the dampers installed upside-down in some pictures - is there any drawback from mounting them like this? Otherwise it seems like the damper oil is just going to drain out over time.

The dampers work just as well upside down, and they are mounted by some people that way specifically to help prevent excessive shock fluid leakage.

Drawbacks? Well they're not as realistic mounted upside down, and technically the setup increases un-sprung weight, which is supposed to negatively impact suspension effectiveness, but it's hardly noticeable on the SRB, because it handles so badly to begin with.

[Re-Bugged 10117]

I did this to mine and has held up well thanks to fellow member @shenlonco

 

[Fuijo 880]

I mounted mine the correct way up because my OCD wouldn't allow otherwise.

I only half fill them with oil, so that there is plenty of room for the piston/rod without forcing oil out.

I also use TRF blue o-rings.

They haven't leaked at all in getting on for 10 years, so I'm assuming they're ok.

[shenlonco 1156]

6 hours ago, Re-Bugged said:

I did this to mine and has held up well thanks to fellow member @shenlonco

 

Thanks I also have another trick that works great see this video.

 

 

[TurboRSR 356]

I used the clear TRF o-rings that @Re-Bugged used on mine as well. 

[Ministrone 1455]

I copied the Shen RC trick but used 0.2mm Tamiya shims left over from my Avante. This stopped all the annoying leaks.

[Jonathon Gillham 4605]

I built mine as per the manual and moved it out of the way and put the car on the printer. The oil all leaked out onto the printer within a few weeks. Probably should've looked into before building...

[moffman 5752]

TBH the SRB dampers don't really do much apart from give it a bit of authenticity I don't bother putting any oil in them the weight of the sand scorcher is what gives it its damping effect after all it is a 40 year old design! Which is why we all love Its quirky driving style if it didn't bounce all around and constantly have the desire to flip over it wouldn't be any fun!

[RichieRich 685]

A quality silicone O-ring and some green slime are great for minimizing the possibility of leaks. At least that's what my therapist says.

 

[Willy iine 18805]

On 10/12/2021 at 5:31 PM, moffman said:

TBH the SRB dampers don't really do much apart from give it a bit of authenticity I don't bother putting any oil in them the weight of the sand scorcher is what gives it its damping effect after all it is a 40 year old design! Which is why we all love Its quirky driving style if it didn't bounce all around and constantly have the desire to flip over it wouldn't be any fun!

I am planning to build mine without oil too.  If it ends up bouncing around too much I'll reconsider or add some friction element inside the damper housing.  

[Mokei Kagaku 2706]

It may have been covered earlier in this thread and it's certainly been covered in the past, but mounting the SRB dampers upside down to reduce leakage is virtually only good for shelf queens. When the model is run and the dampers compressed, the pistons pump the oil out of the dampers regardless of which way they are mounted.

As for an alternative oil, I've opted for not using oil at all. Instead, I carefully cleaned and degreased the dampers and put a blob of Tamiya AW grease on the pistons. Having no idea if it would actually work, I was surprised to see that the damping is more consistent and effective than with any oil I've tried. I don't know how long it will last, but so far, it has worked great. I did this to 9 SRB's with used dampers and it turned out that the size of the piston must be close to original (without excessive wear) for the AW grease to do its job. So after first not taking piston wear into consideration, I had to replace some of the pistons to some with less wear.

[ruebiracer 1046]

Re Re SRB dampers are really good actually. They don´t really leak, just 80% of them are overfilled, so they press out oil. Mounting them uside down creates an air bubble under the rod guide, which reduces the damping. You can test it by hand outside the car with your fingers. It´s like on a real old monotube damper without separating piston. But the y really profit from some better O-rings, like the clear ones or aftermarket silicone rings like Revolution racing ones. Keep in mind: the rodguide assy is the same as on the Rere Hicaps. And they are not claimed as leaky, are they?