Something to be concered with?? (white smoke)

[84 400]

I know there was a thread about this a while back but my situation is a bit different. Okay to start with my truck has been off the road for 2 going on 3 years now. When it was last on the road in 06 before taking it off I had the coolant system flushed. I filled the tanks with fuel and added staybil because I new it would be up for at least the winter. It got started some but mostly sat. The next summer the water pump was leaking out the weep hole so I replaced that and lost a little coolant on the driveway in the process. everything seemed fine and I think I got all the air bubbles out. Anyway fast forward to last month when I installed a new high torque mini starter. The old starter went the fallowing spring so the truck had sat all summer. It seems to run fine but white smoke is still visible even after running for 15 min. I drove it around and it still had a bit of white smoke. I checked the oil and it looked good (no milkiness on the dip stick) I did not check under the fill cap tho.

When we opened the rad cap it was low. So coolant was added. Also the resivar was bone dry . I think That I filed it after doing the water pump but am not sure how much was added. Also when the pump was done it was ran without the cap and fluid was added.

So my question is:
1) Could the smoke be do to water/ moisture in the tank? the tank is now on half full and sat that way all summer.
2) with no coolant leaks evident the only two places I can imagine it could be leaking is the intake gaskets and or head gaskets. there is no leak from freeze plugs .

the motor has about 3,000 miles on it since it was built.

Do you think it is simply moisture in the fuel or a bad gasket.

Thanks for the input and if you have test i can do besides a pressure test (not street legal and the salt is coming out soon I would appreciate it.