Compressor plugs siezed

[Marinegrunt]

Sorry to start a separate post from my current one but thought this one would be okay. There are 2 plugs on the side of the compressor. They look like 2" npt square plugs. I'm having issues getting them out. I let them soak in kroil all night. The ends are somewhat brittle so the edges are breaking off. What's the best way to go about this? I'm considering drilling and burring out. I could then cut the plugs out in pieces while trying not to hurt the female threads.

What do you think? Is there a better way?

 

[sberry]

Why not leave them alone?

 

[c39er]

Best way is with a BIG square drive socket or made up tool to fit the square accurately.
Those plugs are tight!
I take it you want to look inside for rust/corrosion?

 

[Rickss96]

You could try hitting the plugs with a BFH or a sledge. Sometimes that knocks some of rust loose so the Kroil can creep in deeper and do its job. No guarantees tho...

 

[Marinegrunt]

There was some pretty rusty water that drained out so kind of wanted to look inside. There are a couple small 1/2" plugs on top so could just use those to rinse out and see what I can see. I'm sure it's a pretty thick tank so I'll be happy as long as I get the muck out. I wanted to pressure wash the inside but don't have too. Would be able to get it cleaner tho.

Maybe I'll weld up a square socket for the one plug that's still square. It might still work on the one that I jacked up. You're not kidding that they're tight. I had a 2' pipe wrench with a 3' cheater.

 

[sberry]

Put a filter on it, all comp water gets a little rusty. This isn't something causes big problems and have seen as much or more damage from this than it solves. Pump it up, blow it out the drain port a couple times, a little **** laying in the bottom wont hurt a thing.

 

[trackwelder]

Best way for me would be a 1" drive ratchet with a socket and maybe a cheater bar. If the plug is chewed up out comes the 60" pipe wrench and a bit of heat from a oxy/acetylene torch.

 

[TheEquineFencer]

You could try hitting the plugs with a BFH or a sledge. Sometimes that knocks some of rust loose so the Kroil can creep in deeper and do its job. No guarantees tho...

Then I'd try heat.

 

[bob15]

I would leave it alone, you are asking for issues. Rusty water out of a compressor tank is normal.

 

[Marinegrunt]

I might just do that for now Sberry. Was really just hoping to give it a good wash. Maybe I'll try the other one with a socket and see what happens. If no luck just leave and mess with it down the road.

I considered heating it but wasn't sure about heat on a compressor tank. The port sticks out from the tank a little bit and has a thick weld so I'm sure it wouldn't even effect the tank. I know we're not talking about getting it glowing red. I could take it out to my buddies farm and use his 1" impact. I was just out there with compressor in truck too. Now it's unloaded at home. Do you work on the railroad?

 

[md21722]

Heat. Possible need to change the plugs instead of re-use them. There was a good thread on here a while back. With a bright light you should be able to look inside the pump discharge port & tank outlet port and see what you want. Tanks start rusting the day they are made. On new tanks its common to get some rusty water out. After they develop their initial "skin" of rust, the water tends to come out cleaner if drained regularly. The rusty water could have been from moving it. You should have a filter/regulator at each point of use.

 

[AJ1978]

I had a compressor tank I used years ago that I had to change the plug on the side.
Found proper socket
36" Snap on Breaker Bar
Heated it up not cherry red, but warm finally got it to break free.
Bought NEW plugs for it well a bung fitting as I had to tap into it.
No problems, but heat and leverage will be needed.

 

[The Tool Tyrant]

Why not leave them alone?

^^ That! Years ago I tried to remove the same type of plug on an old compressor to change it out for a reducer bushing...Trust me...those type of plugs with the square projection are cast. I had a 3' crescent wrench + cheater bar and the whole square part snapped off flush. I left it alone after that. Had I know the outcome was possible, I would have used heat first. Live & Learn!

 

[Strouty]

Heat for sure, enough to make the paint look like **** is usually just enough. A propane or mapp gas torch is probably not going to cut it. Also make sure the tank is empty before heating.

 

[Finky198]

Could try heating and acetone and Atf mix. I like to repeat once or twice. As said before hammers and vibration can work wonders when used with penatrants. You can also use candle wax as a lube if you don't have the latter. Sometime shocking with cold water helps.

Make sure the system is vented before applying heat...

I like the knipex pliers wrench for those plugs if you had the right size. Dare I say this because they self lock I've put a small pipe extension on em for extra leverage. is it tool abuse yes, And we have a rigid 48", but it's cumbersome to handle. So I use it as a last ditch effort. Work smarter not harder at this. Once you break the bond they should come out smoothly...

 

[matt_i]

I think your original idea is best if you have a nice paint job. I've thought of changing my 1/2" to a 1" NPT and I think these are put in with something akin to red-loctite....which needs the blue wrench and would certainly burn up the paint on the side. The downside is that metal swarf is definitely going inside the tank, but presumably it could mostly be blown out the bottom eventually. It has a big advantage in being *a lot* heavier than air. I'd do the cutting to start with a sawzall or jigsaw, but then switch to a hand-stab hacksaw blade for the final critical end of the cuts.

 

[Marinegrunt]

There are indeed cast. I noticed that when one corner twisted off using a pipe wrench. Now that the one is boogered up I'll probably have to continue with a pipe wrench. A socket might still grab it tho.

It sounds like heat and leverage along with lubricants is the consensus on how to proceed if at all. I probably should just leave it for now but 1 phase motor won't be here until Thursday. If all else fails I figure I could always drill it out and weld a new female coupler to the old or to the old weld. It would just be sticking out a little further than the old. Eventually I want them off just so it's easier to inspect and clean. Being that I just got it it would be nice to start with an inspection and clean tank. I can probably get it clean enough just filling from the top and letting it drain tho. Might wait until I decide to sandblast and give it a paint job. Decisions decisions.

Thanks for all of the advice and tips.

 

[AJ1978]

If you have Oxy-Acetylene just heat it up it crank it out. Once I tried I figured since I have tampered with it I needed to get the thing out either way. You will discolor the paint, but touch it up, and get some new plugs you will be happy.

 

[Bellaireroad]

If you have Oxy-Acetylene just heat it up it crank it out. Once I tried I figured since I have tampered with it I needed to get the thing out either way. You will discolor the paint, but touch it up, and get some new plugs you will be happy.

This... I had this problem with my 80 gal... used kroil... no go... used a propane torch around the perimeter and it was amazing how easily they came out


Sent from my iPhone using Tapatalk

 

[Marinegrunt]

I pulled some smaller plugs so I could see in. There's more than 1/4" of sludge. I think it would be a good idea to go ahead and work on the big plugs so it can be pressure washed or vacuumed out. I'd also be able to see if there's any major pitting. If I didn't get it cleaned out that sludge would constantly be in the back of my mind driving me nuts. I wish there was a bigger plug on the bottom too instead of half inch.

I don't understand how people don't drain their tank. It's not hard. If you're that lazy just buy an automatic one. Heck, you can get a cheap one for $25.

 

[CNGsaves]

Your ********* Plug is likely very rusted . . .
. . .
. . . . . it's very difficult to get Plug out of your ********* !! . .

. .
. .
. . . . . . +1 to leave your ********* well enough alone !!

 

[AJ1978]

If you are like me that will bug you until you do it!
Heat and a 24" pipe wrench should work
Plus 1 on candle wax when heated JUST HAVE A BIG PIECE OR HOLD WITH PLIERS IT WILL FLAME IF YA HAVE IT HOT ENOUGH!
Clean it out change your drain fitting on bottom if the have and adapter in it inner its rusted shut with debris

 

[Marinegrunt]

Finally got them out. I took a pieces of angle, cut them to fit the square head like a glove, welded them up, and welded an old impact socket to the end. I had to use oxy/acetylene and do a couple heat cool cycles. I also used the wax trick. I had to keep heat to it the whole time. If stopped the impact wouldn't budge it. I removed 6 plugs so far. Only two left are the ones for the pump and pressure switch. I see no reason to remove those right now. The two big ones were the only difficult ones. I'm glad I got them out because it really needs a good cleaning. Since the bottom plug is only 1/2", and not in a bung, a shop vac may be the easiest unless it'll all break up with a pressure washer and run out the small opening.

Do I just use some thread sealant or dope on the new plugs? Heck, I need a sealant/antisieze combo!

Thanks for all of the help. So many great tips.

 

[Finky198]

Tape then dope is best 3 wraps of tape for stuff under 3/4" and more for larger pipe. Followed buy a even coat of dope tighten and let cure before pressuring if possible.

I was taught that by an older master plumber and it seems to work perfectly in my experience.

 

[The Tool Tyrant]

Loctite 592 thread sealant. Great stuff AND its smells great too (seriously). I use it on all my compressor related pipe fittings.

 

[Marinegrunt]

Sounds good.

I already had the motor off since I'm waiting for my 1 phase so I decided to pull the pump and pressure switch off too. I'll now be able to roll it on its side so the two 2" holes are laying down and pressure wash through the 3 smaller openings on top. I think it'll be much easier to clean that way. I just hope it all comes out easy. I read somewhere where someone said to throw a bunch of nuts and bolts in it and drive it around in the back of the truck. I've done it with small metal gas tanks before so I guess it could work. I'm hoping the pressure washer will be enough.

 

[mjoekingz28]

Could yall remind me? I have and never done it and may never, but when heating you heat the area 'around' the fastener and not the fastener itself correct?

 

[mjoekingz28]

This... I had this problem with my 80 gal... used kroil... no go... used a propane torch around the perimeter and it was amazing how easily they came out


Sent from my iPhone using Tapatalk

Maybe this is the answer

 

[Marinegrunt]

Correct, just around the fastener. The outside, or female end, will expand loosening it from the fastener. If you heated the fastener it would expand and tighten it up.

I'm not sure if the heat expands it to so much loosen it or if it just breaks the bond. Someone else can probably explain it better than me or say what exactly happens. I do know you heat around the fastener or the female threads.

 

[sberry]

Old dope hard or stuck certainly adds to the problem, softening it cant hurt.

 

[WittHay]

We usually weld a nut onto the rounded off plugs and then use a breaker bar and socket to remove the plug. The heating and cooling of the welding helps loosen the stuck plug. Works good on 1" pipe thread and smaller non cast.

 

[Marinegrunt]

I got the tank cleaned out. I first had it on its side and pressure washed so any big stuff would fall out of the 2" holes. I then welded a couple pieces of small chain to some 1/2" round stock and used a drill to spin it inside to clean any scale. Another round of pressure washing and the tank turned out pretty good. I can still see some paint stick or crayon markings on the bottom of the inside from when it was assembled. That surprised me as much **** there was in the bottom.

Got my 1 phase motor and magnetic starter today so should have it running soon.

Thanks for the all of the help. Might need a hand wiring the starter. I'll let you know if I do.