mid 70's lionel blue comet

I just had a look on the net, and late '70s mint unused sets including 6 passenger cars are being offered in the $400-$500 range. This might help you determine a fair price for just the locomotive.   It doesn't seem to be a prized collectable, and so if I were you, I'd run it and enjoy it as a nice addition to your fleet. 

Hi groundhogslayer,

That set was my prized childhood Christmas present when I was ten years old.  I think Nicole is probably in the ball park for a fair price.  If you get it and decide to run it you need to first open the tender.  These sets came with the "mighty sound of steam" sound board in the tender.  It was a very basic electronic noise maker that produced a chuffing sound as the train moved.  The boards themselves are pretty good with fairly robust components.  However, they are mounted to the inside of the tender with adhesive backed foam rubber.  Over time the foam breaks down and the boards short out to the tender floor.  Before operating, remove any foam residue (it's usually pretty gummy by this age) from the board and tender and replace with fresh material.

These were pretty good runners for their day.  Mine still runs fine.  Modern sets offer much better features and play value, but none of them came on Christmas morning in 1986.

I paid 250-300 for mine. Same deal it was from a friend.

The prices quoted above are optimistic estimates for a complete mint set. The engine alone would be substantially less.

Jim

Yeah, maybe 175.00

That's the old story with Lionel trains, that many people think that the ones they find are worth a whole lot more than they really are. It's that way with many things, though, whether it's old coins, furniture, you name it. That is a pretty engine (actually is a two-tone blue paint job on it), and it may have been worth $400 at one time, but that would have been at least 15 years ago.

It's strange that he got it as a kid and never even bothered to take it out of the box, but I think your advice is good for him to just keep it and let his kids have use it. Hopefully it will be more of a memory for them than it was for him, but at least they'll know that it belonged to their dad.

Introduce him to the Bay, and maybe he can pick up a few of the passenger cars that go with the engine. Makes a nice looking set. Also be sure to tell him about the need to lubricate the engine before running it, which will be very important for an engine that hasn't been used for decades. Usually this includes removing and then replacing the old dried-out grease that was applied at the factory.