Leaking EFM 520

Hi everyone. This is my first post here but i have been reading this form for years and first just want to say thank your for all the helpful info i have gotten from it!
Now on to my issue lol. I have burned coal for about the past 12 years and had great luck with all my stoves. I have always had hot air stoves from hand feed shakers to my last hyfire but i have been wanting a boiler for a while and decided when we bought this next house i would get one. I picked up an older 520 (late 50's early 60's i think, round door). The unit was in pretty good shape and was in service until the end of last winter when it was removed. The previous owner had taken good care of it and it didnt need much for repair other than a good cleaning. before i installed it i pressure tested the tank to 40 psi and let it sit over night with no pressure loss, so i thought i was all set. well i got it fired up about a week ago and all was great..... until last night that is lol. When i went out this morning pressure was down to about 5psi so i started checking all the connections and piping. I found a leak directly above the burn pot that was dripping down on to the fire. I dont see any cracks or damage, it just looks to be seeping through. im sure there must be a rust hole or a crack there but i cant seem to find it. I have gotten it shut down and drained so its not leaking any more. So my question is where do i go from here? Are the tanks repairable where the leak is or should i be looking for a new tank? Any thoughts or advice is welcome..Thanks

It is very uncommon for these boilers to leak in that area unless they are seriously corroded. I would remove the baffle, give it a good cleaning/vacuum, then refill the boiler and watch for a leak so you can pinpoint it. If the boiler is rusted through it is likely junk - but if it appears solid and is leaking at a weld, it can probably be repaired.

Ok thanks for the quick reply. i will get it cleaned out and wire brush it to see what i can find. ill post some pics when i get it cleaned.

Is there a boiler sealer product ? I think I heard of something that actually is added to the boiler.

Yes, from experience I can say Oatey Boiler Liquid is effective at sealing leaks. Maybe others have experience with other specific products.

Mike

Hercules.

https://www.oatey.com/2377238/Product/Hercules-Boiler-Liquid

If the leak is from a hairline crack in otherwise solid steel, a stop-leak product may be all that is needed. If the boiler is rusted through, no amount of stop leak is going to correct it.

Find the leak...
Determine the cause...
Fitting loose, bad weld, crack but sound or rot...
You don't want the boiler to burst from rot...

I guess I am assuming that the 40 psi pressure test described by the OP would have identified any major rot issues affecting the integrity of the boiler vessel. I think even some new boiler mfgrs recommend use of boiler liquid during installation, which can address isolated flaws in materials, welds, etc. that may exist. Obviously it has limits, but if there isn't a big rot issue it can provide a cost-effective remedy.

Mike

Finally got some time to work on the boiler. I wire wheeled the tank and tried to get it cleaned up a bit. Man it tough working on the inside of a round door! Got it cleaned up and found the hole/crack sort of. The tank does have some rust but doesn't seem rotten. I took a hammer and gave it a few good whacks and I didn't punch through or cause any new holes. I think at this point I'm just going to tear it all back down and remove the tank so I can get at it better. I contacted scrapper and I might just replace the tank depending on what he has. I attached a few photos. The wetspot in the middle of the dry part is where the hole is. The last one is after I beat on it with a hammer lol

Never seen a boiler do that unless it was a steam boiler, that was taken out of service if so junk it just problem in the future, i dont save steam boiler i womt touch them i got burned on a couple

Wow! That's a shame about your boiler. Replacing it won't be easy, that's a big job.

The only thing I can think of that would cause that is firing it with the water level too low. As Ryan pointed out, that is more likely with a steam system then a hot water system. I'm sure Scrapper can fix you up with another boiler to replace it.

-Don

Thanks for the replies. I'm not sure if it was set up for steam or hot water. Not looking forward to taking it all apart again! I just got it all put together. There was nothing to indicate if it was steam. How can you tell? There was none of the controllers with the boiler when I got it.

Sight glass...

Looks like a pinhole. I would drill it out and weld it up. Drill right through and go less with larger drills until you have a nice scooped out spot to weld out.