Air leak

[Heetseeker]

First post, first Class A. Just picked up a 98 Gulfstream 36' with a Cummins 8.3 and i've been going through the engine maintenance and chassis systems. It's a lot to tackle and i've got manuals and this forum. Checking the air system and i'm hearing a leak after we get to full pressure and the engine shut down. I got under and poked around with a bottle of soapy water and found a 'valve' that is leaking between the two air tanks up front. (Spartan chassis). I could use some help identifying this part so I know what parts to purchase and fix it. Thanks in advance!

[FIRE UP]

Originally Posted by Heetseeker

First post, first Class A. Just picked up a 98 Gulfstream 36' with a Cummins 8.3 and i've been going through the engine maintenance and chassis systems. It's a lot to tackle and i've got manuals and this forum. Checking the air system and i'm hearing a leak after we get to full pressure and the engine shut down. I got under and poked around with a bottle of soapy water and found a 'valve' that is leaking between the two air tanks up front. (Spartan chassis). I could use some help identifying this part so I know what parts to purchase and fix it. Thanks in advance!

Heetseeker,
For some odd reason, your pic is real small and, it won't allow me to click on it to zoom in. But, for lack of another or, any bit of "on line " approach advice here, I'd take that picture, print it out and zoom down to your local Freightliner or, maybe even Napa and show them the pic to help identify just which component it is in the air system.


Or, if you're a bit handy, you may be able to remove that valve/component and take it apart to see just might be the culprit. Could be just an o-ring that's gone bad. Never know.
Scott

[Heetseeker]

Thanks...I've been looking online at air system components and it looks like a pressure protection valve? Not sure what is going on with the pictures.. i'll read up on that too!

[Heetseeker]

lets try this again...

[Spk64]

That is indeed a pressure protection valve. Looks just like one I replaced this spring that was feeding the air suspension on my Spartan Chassis. Prior to replacing my tanks would fully leak down and required a long time to fully air back up. Now when the air bags are dumped the tanks maintain around 70psi with the new valve.
BTW I also had a check valve leaking and replaced next to the Pressure protection valve.
Purchased online thru ebay.
https://www.ebay.com/itm/NEW-9055410...72.m2749.l2649

[Heetseeker]

Wow! Thanks for the link. Ordered that valve and will be leak free in a week or so.

[FIRE UP]

Wow,
You guys got me thinking. I've had a "slight" air leak ever since we purchased our present coach, an '04 Itasca Horizon 36GD with the 330HP C-7 CAT about 7 years ago. It used to hold pressure somewhat decent after I hit the auto leveling HWH system for quite a while, as in a few days. But, when I hit the auto level now, as soon as the last jack is set, and the HWH system is satisfied and shuts down the leveling system, I still hear some air escaping somewhere. I never used to hear that for the longest time, as in the first few years. But, it's almost every time now.
So, as soon as we get back from an upcoming trip, I'm gonna dive into the search for the mysterious air leak.
Scott

[Toribk]

Scott,

I'm late to the party, but check the back of your air gauges. That is where I found that the brass push connection mounted in the air gauge itself was leaking for the primary air system.

Good luck.

[Vaflatlander]

From the picture looks to me to be a check valve moisture ejector combination. I would take your picture to the nearest truck shop and I'm sure they'd be able to identify it.