Leaky Maruader

Last night after shooting a few rounds, I pumped up my .25 Mrod.
Checking the pressure later it was down 500 lbs. An hour later it was down another 500 psi. By this morning the gauge read 0.

So, thinking it was the check valve on the fill end. Suspicion fell on the check valve because after shooting, the rifle held pressure for about 1 1/2 hours. Then started leaking after topping off the pressure.
Having never taken it apart before I was curious to see the inner workings.

The check valve is a stem with an 0 ring inside the quick detach nipple. I took it apart wiped the clean grease off of it. And with some advice from D-RIG used silicone grease on the 0 ring for re assembly.

310 strokes of the pump later it has 2500 psi showing on the gauge. I have been giving 50 or 70 pumps at a time. The valve on the chamber end must not be leaking, but really will not know if the check valve is holding until I disconnect the pump.

Still holding 3000 psi, must be okay.

Look out starlings!

A spray bottle with some dish soap can be your best friend
when trying to find a air leak spray the fill nipple and around
the pressure gauge these spot are where they normally leak from .

When it rains all guns get wet . Some PB even advertise what their rifles will do when pulled out of mud . If the soapy spray bottle fails . I have and have not removed some wood . Filled the bath tub with enough water and submerged the rifle . After the leak is found in the rifle remove it . Then blow dry it and lube it . Don't forget to repair the leak as well .Marvin

I had given some thought to smearing a little spit over the fill nipple, like checking a leaky valve on a car tire. But read online about the importance of keeping PCP guns dry inside.

Really, throwing the gun in the bath tub will make the leaks show, what the heck, you have to take it apart to fix it anyway!

Mellowairman, you probably have thecleanest guns!

You do want to keep water out of the tube but the air pressure will do that . Be for the bath I do stick the muzzle end in a bucket of water and watch for bubbles . My Korean BB with all those o rings on that end have taught me to search for leaks . I do dry fire to blow water out of the barrel and then a few patches with a little lube .Marvin

My first PCP gun was a used Marauder that leaked. The culprit was the valve plunger. Tore it all down and fixed it for the cost of an oring kit, a new plunger, and some silicone grease. That was six months ago, and she still hold air beautifully today.

Good luck with your Marauder, they are sweet rifles.

Still holding pressure good. Have been to busy shooting CMP, and working appleseed to shoot the air gun much.

Glad to hear that, clodhopper!