TSP use under primers

TSP can leave a residue behind when improperly rinsed, and this can cause crystallization behind our primer that interferes with adhesion. You can use TSP, but it must be thoroughly rinsed prior to application of any Zinsser products. A better option is to use a "no-rinse" TSP, Such as Krud Kutter® No-Rinse Prepaint Cleaner TSP Substitute or a mixture of household ammonia and water (which leaves no residue behind).