The Dow Jones Industrial Average (^DJI 0.69%) is cruising toward another record high today, up 0.02% and at one point peaking above 16,100 for the very first time. Stocks are up despite a report from the National Association of Realtors that pending home sales index fell 0.6% to 102.1 for October, the lowest level since last December. The government shutdown may have kept some buyers on the sidelines, while elevated mortgage rates are dragging sales as well.

One big outlier from today's gains is Boeing (BA -0.76%), which also happens to be the top Dow stock of the year. The aerospace giant is down 2.2%.

Today's issues again come from the 787 Dreamliner, which has had its share of problems this year. Boeing over the weekend warned 15 airlines that 787s with General Electric (GE 8.28%) engines should avoid thunderstorms because of potential icing problems. GE says the problem can be fixed with a software update, but it's the mounting problems with the 787 that has to have investors a big skittish today.  

In January, the FAA grounded all 787s after two battery fires developed on parked aircraft in Boston. In July, an Ethiopian Airlines 787 caught fire due to a faulty emergency beacon. Norwegian Air Shuttle grounded its fleet because of oxygen supply, brake, and hydraulic pump issues. Finally, last month, a Polish-owned 787 was grounded after the system that identifies planes to air traffic controllers malfunctioned.

That's a long year for Boeing's engineers, and fear of engines icing up doesn't help matters.

Time to sell the Dow's hottest stock
Boeing is up a whopping 80.2% this year, despite the problems highlighted above. A big driver has been increased orders from airlines around the world, which are still betting on the 787, as well as the 777.

It might be time to start taking some profit from a company that still has some fundamental operational challenges. The 787 won't be a flop, but it has had a challenging launch and Boeing may not be able to live up to lofty expectations. Shares now trade at 18 times 2014 earnings, a steep price for the stock. I would take some profit and go hunt for better values, even within the Dow Jones Industrial Average.