I got a 252 Lionel engine and a set of freight cars for my first restoration project. So far all is going fine, but have this tank car does not seem to fit with the rest of the cars. All the other cars are 800 series freights with the hook type connectors, and two sets of wheels on each truck. This tank car only has one set of wheels for each truck - not really a truck but just connected to the frame, and it has the hook and lock connector ( probably misnaming it) like the engine does.
On the bottom the instructional sticker is still on it about oiling and stamped on that sticker is the number 804. The “zero” 
could be something else but that it what it looks like to me. i am new to all of this and would appreciate any information about this car.
Welcome to the forum! I hope you will share your restoration progress with us. The car you have is a Lionel #804 tank car. Your terra-cotta colored tanker was offered from 1926-28. Basically Lionel offered two sets of O gauge freight cars before 1935. They both are typically referred to as the 800 series. They were the less expensive and smaller 4 wheel freight series and the larger, more expensive 8-wheel series. The style you have is the earliest version of a tanker Lionel made. Four wheels, no ladder, no railings, rubber stamping. Just a simple tank with a brass dome. The 8-wheel tanker that would match your other freight cars is the #815. I’ll try to post a picture of one sometime. If you need more info, just ask. Good luck with your restoration. The 252 electric cab engine is a great little workhorse.
Thanks for the wonderful information. Besides everything else I am sort of a history nut and love the history behind these trains. I have been retoring and refinishing furniture for years and nothing I enjoy more than bring something destined for the trash back to where others can still enjoy them.
That 252 engine was most impressive, and I could tell by the worn center of the pick up rollers it had seen many trips around a track. The wheels were shot, and the motor frozen, but after a long and involved cleaning, and repolishing the inside of the reversing unit it just purrs away now. Amazing how well built things were done back then.
I have taken the old paint off the engine. First I cleaned it with rubbing alcohol and noticed some of the paint coming off with the alcohol. So, I used a large artist’s painters brush with the bristles cut halfway up to firm it up with stripeze and just wiped the brush on a rag to remove the paint. Then after most of the paint was off I used a softer brush with a lot of alcohol scrubbing with the softer brush and letting it dip onto a rag, and that got down to the bare metal. Was no need to boil in detergent or anything. Got all the paint off inside and out in less than 15 mintues that way.
Thanks again for the infomation
[#welcome] jms2222,
I just looked up the 804 tank car, it is pre war, 1923 to 1928. What looks like a zero is probally the indicator stamp for O gauge back then. In good condition according to Greenberg’s guide it would be worth $28.00, excelant condition $49.00. Your car as is might be worth around $15.00, only because it is pre war, repainted I am not sure what it may bring.
Lee F.
I think Lionel’s couplers were called “Latch” and then “Box” and lastly, “Knuckle”.
-b in B