Cal Club Autocross Forums

Are there obvious places that these reservoirs leak, and are they easy to fix? Just use soapy water to find leaks ... and fresh teflon tape on the connections?

Are you referring to a fluid leak or a gas leak?

I'd guess that gas leaks are about 5 times more common than fluid leaks, based on my experience with this kind of shock. Almost all of the gas leaks are due to a faulty Schrader valve or a leaky rubber septum.

If a UV lamp doesn't work (go to PetSmart and get a 'StinkFinder' for ~$15) then the barnyard way to find fluid leaks is to throw some powdery dirt on the part. Yeah, you'll be washing the shock off afterwards...but you'll KNOW where the leak starts from - it's where the most dirt is.

Gas ... Nitrogen. Not physical connection between gas and fluid in the Penkse I believe. There is the schrader inlet valve, I believe the plate on the end of the Reservoir that the valve is built into, the connection between the armored hose and the shock body, the outlet from Reservoir to hose and the hose itself.

Do the Penske's Tend to leak Nitrogen? Guy rebuilt them around June.

It's not that unusual for any gas-charged shock to lose gas pressure. The shock on my mountain bike only holds pressure for about six months. It's possible but pretty unlikely that the work was done improperly - Guy's a sharp cookie.

You could replace the schrader cores - I'd bet that's more than likely the cause of the problem and a cheap and easy potential fix.

Any high performance aftermarket part requires a lot of checking and maintenance. The nitrogen pressure in your shocks should be checked and set before each event along with tire pressures, fluids, etc.

We're about to buy one of those special pressure gauges for the shocks, so we don't have to keep using Henry's. Just wanted to see what others are experiencing. We've checked the reservoirs two or three times in the last six months. Both times they've needed added pressure. When we have our own gauge we can check before each event.

Mako--The most common nitrogen leal would be at the schrader valve. Spit , water or soappy water will all do the trick. The o-rings that seal the cannisters hardly ever need replacing or leak. I can't remember for sure, but I don't think we replaced any of your seals before, except one shaft seal? Buying the correct tools, is always a good decision. Guy

Mako Koiwai wrote:We're about to buy one of those special pressure gauges for the shocks, so we don't have to keep using Henry's. Just wanted to see what others are experiencing. We've checked the reservoirs two or three times in the last six months. Both times they've needed added pressure. When we have our own gauge we can check before each event.

How much are they leaking? From what to what? Attaching the pressure tool will give you a lower reading as it's got a small chamber that needs to get filled (depending on the tool, the delta will be different). Using anything that doesn't allow the valve to close before the pressure is released is unreliable (advantage Presta).

My Penske's rarely leak, but any time a Schrader valve is involved there is room for error...

Checked them three times now over the last six months ... each time at least one was completely flat ... not always the same one? ... the others half way down. 150 psi in front, 120 in back.