Cartridge Cylinder Leak Through Top

I have a Black Diamond PRC90DB Cartridge Filter unit. The cylinder that houses the filter has a removable lid with a pressure gauge and an air release valve. It has tiny leak going THROUGH the top plastic! I can't even see a hole, but when the pump is on, drips come through the top. The leak is not where you'd think it would happen (the threaded openings or a seam.) It is through a solid part of the plastic top! I tried to coat the inside and outside with flex-seal but no dice. I guess the high pressure of the unit pushes right through. Anyway, any recommendations for repairing -- OR -- can that top be purchased as a replacement part?

IF,,, you can verify the EXACT location of the leak, AND it is a pin hole instead of a crack, you can fix it with a drill and epoxy like JB Weld. Just clean the area (on the inside) very well with alcohol or white vinegar, lightly sand around the area on the inside, drill a small hole (approximately 1/8"), cover the hole with duct tape or masking tape from the outside, the fill the hole (make sure it is completely worked ALL THE WAY into the hole) and coat the area around the hole (maybe 1" diameter) with epoxy. You can leave the tape off the outside if you don't mind the repair being a little messy and the epoxy thick enough that it doesn't run through. You MIGHT be able to fix a small crack the same way, but drill a hole centered at each end of the crack, this will stop the crack from "running". Then apply epoxy out to about 1/2" on each side of the crack and 1/2" past the ends. There are several flexible marine grade sealants on the market which might also work, as well or better than, JB Weld.

Another solution for a pin hole that is UGLY but almost always successful, is to drill a hole just big enough for a Stainless Steel machine screw. Coat a SS flat washer LIBERALLY on both sides with silicone sealant, put on the screw, put the screw in the hole (from the outside), coat another SS flat washer and put on the screw inside, then install the nut and snug things up.

Good Luck

Pappy

Thanks. Before I try the screws, I wonder if I could just put a layer of the epoxy on the inside and outside of the hole? I would hate to drill through when the hole is so small. It's not even a pinhole, it's microscopic! I can't even see the hole, I just see the water drops forming! I still don't understand how a hole developed there... the plastic is solid and about 1/4" thick! Can I seal it with the epoxy or any other substance? (As I said, Flex Seal didn't work. It stays rubbery and porous. I need something that will harden solid.) Thanks again!

It wouldn't hurt to try some marine grade silicone sealant (boat store, Lowes, Home D, wallyworld) on the inside. Putting something on the outside is likely to fail because the pressure may blow it loose. If it's inside the pressure trys to force INTO the hole. Just be sure to clean the surface thoroughly before you apply the sealant, then let it fully cure before you reassemble the filter.

Hope this helps!

Pappy

Epoxy putty, or JB Weld is great stuff, as long as it doesn't get into anything else.

JB Weld worked great! Thanks for the tip! There were actually a few micro-leaks, so I've gotta repeat the process, but so far so good. Still perplexed how these leaks occurred in a solid piece of thick plastic. Anyone else ever have this happen?

I can only guess. Sounds like either too much pressure or some acid got in there. Epoxy Putty and JB Weld have been long-time friends of mine! I once replaced a heater core in a car, only to nick the new one putting in a better radio. Rather than replace the new one (changing ANYTHING in a 1981 Chevy Citation was hellish experience--my mechanic had nightmares about the carburetor!), I used some epoxy ribbon putty, and never had another problem...with the heater core, that is. I was ecstatic the day I traded that car in on a 4x4 pickup truck!

UPDATE: Drip leaks continued into this season. Practically had entire inside and outside covered in JB Weld, but drips still bled through (Sill perplexed how this happened - you can't even see a hole but drops escape. I guess the pressure did it.) I found a replacement lid for $30 by Hydromatic - identical to my Black Diamond. Working great again. Still interested in why this may have happened so I can prevent a recurrence. Thanks!