“Rhino and Linex will NOT coat over rust” it the product will coat over rust, it the operator should not. It is often applied over a primered body, something the Linex installer does not do, nor is there anyway he can vouch for the quality of that primer paint or the metal under it.Click to see full answer. Similarly, it is asked, does bedliner stop rust?No. Even if you have a little rust, it will just mask it. The rust comes through the body and usually doesn’t start as surface. The liner will mask and then make the rust worse.One may also ask, can you apply Herculiner over rust? HERCULINER adheres well to sound-painted metal. Most rough metal surfaces need not be primed; however, on applications of extreme wear, such as step nosings, a primer is recommended. All rust should be removed down to the bare metal before applying HERCULINER. Subsequently, one may also ask, can you spray Rhino liner over rust? Real easy to use, just wire brush the loose stuff and put in on with a spray bottle or a brush over rusted or bare metal. After that, it can be primed and painted or use a bedliner material directly over it.Which is better roll on or spray on bedliner?Compared to spray liners, a roll-on bedliner is much cheaper and relatively easier to apply. If you’re looking for a budget-friendly option, a roll on bedliner is a good choice. Furthermore, there are plenty of options available when it comes to choosing just the right color for your vehicle.