Drain cap destruction

Oil drain cap

The AG200 has a slightly unusual method for draining the engine oil. Instead of a generic old drain plug, it has a drain cap which is also used to hold a spring loaded oil strainer. The AG200 engine has a cool design where it has a big strainer at the bottom of the engine to hold back the big chunks, while the finer oil filter (on the other side of the engine) keeps the rest of the damaging material out of circulation. Now all we need to do is get people to clean them and replace the oil! …but I digress!

The real aim of this post is to guide people on how to not chew up the drain cap. Here is the crux of it; the hex head on the cap is 19mm, if you use a shifter you will wreck it. If you use an open end spanner you will wreck it. If you use a double hex ring spanner you will wreck it. If you use a double hex socket you will wreck it. If you use a cold chisel you will…you get the idea!

AG200 oil drain capThere is one effective way to get it off without damaging the cap – a single hex, 19mm socket. Where do I get one of those I hear you ask, drop into your local tool shop and ask for a 1/2 inch drive, 19mm impact socket. It will be black (black oxide), and have a hex interface to match the drain cap. They are cheap and make your life a lot easier as far as oil changes go.

19mm single hex



4 thoughts on “Drain cap destruction

  1. Well mate, first gotta say I was rapt when I found ya site. It’s gonna be me bible for the next few months as I bring back to life an old classic.

    Heh, the first order of business was to change the oil. I knew it’d need it and damn was I right. After finding ya old site and reading about stripping the bolt I followed your advice and got the socket.
    Unfortunately due to the fact the poor bloody bike not having had an oil change in its entire life, the sump plug was seized in there like a mongrel and it stripped it anyways. I had to undo the access port on the side of the motor and lay the whole bike on its side. The oil that came out was black as the ace of spades and the same consistency of water.

    ……..but the fun continues and the machine shall live again. Thanks for the tips and here’s to happy cruising.

    1. Sounds like you have a tough one! Dont give up!
      I probably should of mentioned in my post that if there looks like corrosion around the drain cap, to hit it with an impact driver or rattle gun. If you haven’t got one of them then a few mild taps with a hammer on the cap (via the socket) will help things as well.

  2. I have a ’82 XT200 and stripped the living hell outta the drain plug even after following your tips… the plug and block had literally become one lol… no amount of tapping, power bar, swearing made a difference…

    I have resorted to using Pratley steel to permanently bond a 19″ socket to the plug and we’ll see how that pans out after its set properly 😉

    1. Hi Jonathan
      Sorry to hear about that. Attaching a socket is a good idea for a fix. I think people do them up too tight and if the o’ring is hard and flat it pays to replace that as well.

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