Dorman Expansion Plugs & Cup Plugs

[Guest]

I recently purchased an orange metal box labeled Dorman. The inside of the lid lists different size expansion plugs and cup plugs and which cars they would be used on. There are 16 compartments, each containing what I believe to be are the expansion plugs & cup plugs. What exactly is an expansion plug & cup plug? I would like to sell these. Would it be better to sell them as a lot in the box or would collectors be more interested in buying just a particular size? Thanks for any information you can offer!

[Guest]

Hi - CJ<P>What you have, are typically called "freeze-plugs". SOME people think they are there to protect the block or head casting from the explosive pressure of freezing water. Not true. You forget to have the correct ratio of anti freeze...and it drops below freezing, and stays cold long enough for the water in the water passages to freeze, it is GOING to crack. PERIOD.<P>They should be called by their correct terminology...CORE PLUGS. They are used to plug the holes that must be in the casting somewhere, as part of the casing process (unless the casting engineer has left himself other "outs", such as, for example, the big open water-jackets in classic-era large Packards) <P>My understanding is that ALL the standard sizes of "core plugs" are still available "off the shelf" from any well-equipped parts house. I am NOT sure about this...there MAY be some classics that use an odd-ball size.<P>I dont know what to tell you about value. Perhaps the box itself has a curiosity value.<P>Pete Hartmann

[Guest Chuck Conrad]

Today I visited an old auto parts store in downtown Longview Texas, called Texas Auto Parts. There was little in the place that was post 1975. I'm not sure what keeps them in business, but I'm glad they were there for me to browse around. The parts counter guys were much older than their stock. They were very nice to me, and invited me to look anywhere I wanted. They had an entire gondola display of "freeze plugs." There were more sizes than I ever knew existed. The average price was about 75 cents each. Some more, some less. Now you know.