Hi Barney,
The TD plug is brass, and the sump is cast aluminum. Given that the
bernz torch with the standard tip can put out a lot of heat, don't you
think that playing the flame around the plug onto the sump would have the
desired effect of getting expansion of the aluminum to change its grip on
the brass threads. Wouldn't this take place before the oil could
effectively redistribute the heat?
The plug itself is large. I don't remember what the As used, but the B
hole is about 1/2 inch, and I'm guessing that this is 15/16 or so. In
'53, only some of the chassis pieces were UNC thread. Everything on the
engine was either BSF, BSW or Nuffield's Mad Metric. Frank needs to get
this plug out w/o harming the hole in the sump.
MG must have expected a lot of pieces of engine to drain out with the
oil, judging by the size of the plug. The oil change instructions were
to remove the felt filter and to rinse it in paraffin, then reinstall the
thing, replacing only at alternate oil changes. Can you think of a better
way to reintroduce into the lubricant (single viscosity specified) most
of the material that got filtered out the first time?
Bob
On Tue, 30 Dec 1997 18:19:53 EST barneymg@juno.com (Barney Gaylord)
writes:
>
>On Tue, 30 Dec 1997 10:39:02 -0800 "Frank R. Krajewski"
><frankk@businesson.com> writes:
>
>>Looking for assistance in removing the brass oil drain plug from my
>recently acquired 1953 TD. ..... quite a rounded plug at this time.
>Would the application of heat to the plug or the pan (which expands at
>the more rapid rate: brass or aluminum?) be of any value? .....
>
>Whoa there! No sense applying heat to an oil pan full of oil. The
>oil would keep the pan cool while you're heating the plug, the plug
>would expand from the heat while the pan wouldn't, and it would just
>get tighter. You would have to get the oil out first, all of the oil.
> And I don't think sucking it out through the dipstick hole would get
>enough of it out, so you would probably be in for removing the pan
>first.
>
>Creative suggestion here:
>
>Start by drilling a hole through the plug to let the oil out. If
>using an electric drill, be careful not to get oil into the drill
>motor. Oil is generally non-conductive, so not much risk of a shock,
>but it could screw up the motor if enough oil got inside.
>
>After the oil is out you can go after the plug with heat. Of course
>have a fire extinguisher handy just in case. Plug the oil filler and
>any crankcase vent holes to stop air circulation inside the engine.
>If you manage to ignite the oil in the pan while applying heat, it
>won't burn much without air circulation inside.
>
>The brass is going to expand faster than the steel, so it probably
>won't come loose with heating. It could however come loose with
>cooling. You might try heating the plug and the pan together, then
>apply Ice to the plug, and try unscrewing it with the vice grips while
>the pan is still warm. Gloves would be in order here. If that fails,
>there's always other ways.
>
>As an alternative, drill through the plug to let the oil out, then go
>after the plug with an acetylene or map gas torch. Brass will melt at
>a much lower temperature than steel, so you should be able to melt the
>brass plug and let it drip out of the threads by the time the steel
>starts to glow dull red, much like melting solder. Do not let the
>molten brass drip on you! Also do not heat the steel part beyond
>bright red or you run the risk of distortion in the female threads.
>The threads will probably clean out well enough to screw in a new plug
>(after cooling), otherwise you will have to chase the threads with a
>tap.
>
>Now tell me it's some really strange thread and you can't get a tap
>for it. For the purpose of cleaning out an existing thread, you can
>sort of make your own tap. You need a steel part with the proper male
>thread. Hand file a notch in two places opposite each other in the
>leading corner of the male thread. The notches will act as cutting
>flutes on a tap. Use the modified part to chase the threads. If that
>modified part happens to be a new steel oil plug, you can probably go
>ahead and use the same part for the working oil pan plug.
>
>This sounds like a bit of a fuss, but if it's a brass plug, and if you
>have a good torch, it should be a straightforward job, pretty easy to
>get it right, and fairly hard to screw up.
>
>Keep us informed,
>
>Barney Gaylord
>1958 MGA with an attitude
|