98 F350 diesel hard to start when cold
 

the F350 diesel i am currently driving is hard to start when cold.https://www.truckforums.com/micons/m13.gif In the mornings it wont start at the first crank so i have to wait a few seconds to give it another crank or two untill it starts. Last Feb when it was cold i would crank it and eventually grey "smoke" would come out the tail pipe but it wouldnt start . The last driver used to use a can of starter chemical which he dised into the air intake. I have had it looked at a non ford dealership and they say they have adjusted the diesel injectors but now that mornings are cold the same proble is surfaciong again.