Question????

In 1997, I bought a campbell hausfeld air compressor w/20 gallon tank for a few hundred bucks. I left this one outside for easy drive-up access.

So, now, after 20 years of use....the "head" gaskets have failed. I can buy new gasket set for about $40.00 including shipping.

My concern... is the tank may be rusted from the inside and have a weak spot and possibly blow-out. (no expiration dates stamped on tank, that I can see).

Would you spend the $40 to get the air compressor running and take the chance...or just buy a new one?????

If it were me, I would NOT risk it!! Compressors have greatly come down in price, and you could get a new one, coat the insides against rust, then leave it sit out without further fears. Better to err on the side of caution. Besides, you never know who else might be around when that tank decides to blow! Isn't a matter of if, but when.

Outside and uncovered?

Crazy Horse- yup, same way with my table saw(it's been sitting out for 20 years also).

Fill it with water full and then put pressure on it to the tune of about 1.5 times your working pressure. 100 psi working 150 psi test. The water will not store any energy and just leak out if you have a problem spot and not be hazardous like if doing the test with all air pressure.

Have you kept the water drained out? The unit being outside or inside makes no difference on internal corrosion. If it was kept drained it will last indefinitely. If you don't drain it regularly it is wise to replace it. I always put a hydraulic hose on the drain and a ball valve on that. Gets it out to where you can get to it and if you drain daily all the water is sitting in the hose instead of the tank.

Is the pump still in good shape? Was it pumping up to pressure pretty fast before it failed?

Some mechanics have sort of a tiny remote digital camera at the end of a flexible tube, a friend of mine has one, he can go into spark plug holes and other remote places and see what's in there. Would be interesting to see what the inside of that tank looks like. Someone mentioned coating the inside of a new tank (should a person buy one). Never heard of that, maybe some guys do that though.

Scrap it and go by anouther one it's not worth the risk. I've seen a pressure vessel rupture and it wasn't pretty. I had the motor fail on one in my shop last year and could have fixed it for about half the cost of a new one but it was close to 20 years old. I scraped it and went and bought a new one.

I can't remember what I paid for them but I've bought several head gaskets and I know I never paid that much for them. I think if you shop around you could probably get one for around ten to twelve dollars.

As far as the tank I wouldn't worry about it unless it give you reason to. Just don't purchase a new Campbell Hausfeld compressor. They are not near the same quality as they used to and I don't think they put any sealant at all on the inside of the tank. I have one which when I drain the tank it's a thick steady stream of rust coming out. I need to go into it with an inspection camera to see.

Got a Campbell - Hausfeld contractor's compressor, with twin tanks and MADE IN USA pump. 30 years old. Bottom of one tank blew a hole out, and the new tanks do not have any interior liner at all... dumb, if you ask me. Long story, I ran some hose clamps around the tank with a rubber patch, over the hole, and haven't worried about it since. Been 2 years now. No leaks. I thought it would not have a catastrophic failure, maybe another slow leak.

I believe that is called hydrostatic testing. The safe way to pressure test things.

If you've drained it regularly, the risk is no greater with your outdoor compressor than one kept indoors. In fact, the outside air is likely to be less humid than the air inside a heated shop.

That said, a twenty year old C-H compressor is nearing end-of-life.

kcm.MN- Thanks. I'll shoot a couple of holes in the tank
and send it to the scrap yard.

It all depends on your age, If you are likely to live 20 years buy a new one. If you are my age , you don't need the one you got.

Local yard won't take tanks unless they are cut in two.

teddy52food- "Local yard won't take tanks unless they are cut in two."

LOL! I was at my local scrap yard last week and I saw piles of rusty 20 lb. propane grill tanks. They were not cut in half.

Found it! Here's a video from a guy who sent an endoscope down into a compressor tank, almost twice the age of yours. He also has another video where he cut open the tank from another compressor to see what was inside.

After the video from the endoscope, he took a couple of magnets and pulled lots of rust from inside the tank, stating how the rust flakes were still quite moist even though no water was blowing out. Venting the air from a tank releases pressure and excess (or puddling) moisture, but not the moisture film, which continues to eat away at the inside of the tank.

In your case, you say how the compressor has been outside for 20 years - I hope at least covered. In any case, ANY such tank that is not within an insulated area is going to be more prone to temperature swings, which can cause additional condensation on outside of tank. Add in nighttime dew. Now add in any bug juices or bird poo that might be somewhat corrosive. Add in grass/leaves blown in by wind or the lawn mower, let sit with moisture and it'll rot, not helping the tank any, that's for sure!

So, if you write a post stating your concern against the tank failing, then the best course is to replace the tank. As the compressor needs repair, get a new compressor.

"Most" such tanks will not blow, but rather develop small leaks. If someone continues to use the tank even with it leaking, then eventually it will blow. If someone tries to "fix" the tank (like when welding), then there's a good chance they are creating a ticking time bomb! The 2nd link below is from a security camera that happened to catch one air tank that blew, and it wasn't a pretty sight! That's why I wrote the post as I did.

https://www.youtube.com/watch?v=OaN8blYYElg
Air Tank Endoscope

https://www.youtube.com/watch?v=KVP_A7eGYxw
Air Compressor Explosion

See if you can find an ultrasonic thickness tester to borrow. That way you could see if it is thinner in one area than another. You should be able to see the lowest spot. That will be the area it would rust thru first. If there is rust on the outside and near the lowest point, I would guess it is about done for.

I brought a well pressure tank back home from the salvage yard. They refused to even let me give it to them.