I have a 90' IDI 7.3 and when starting it blows blue smoke when I start it. I live in Houston so I know its not due to cold weather. A friend of mine told me that it could possible need a ring job, but thats a lil expensive and I am trying to do the cheapest fix first. If anyone could help out or have any ideas, suggestions it would be more than helpful.

 

Blue smoke is a sign of burning oil.. oil could be leaking past your valve seals while the vehicle sits over night. Older trucks with a lot of miles on them do this because the seals get old and worn out but once it gets warmed up the seals become more plyable (sp) because of the heat of the oil. Another thing that you might want to check to see if its the rings is the amount of blow by, pull the oil cap off the motor or remove the dip stick with it running and see how much pressure is coming out of the crank case.

 

I wouldn't get to worried about it, definetly not worth overhauling the motor over it.