Update on shrinkage. It seems to be the FP Plus. For ease of use and carry, I was pouring the FP Plus into a used Lucas 5.25oz treatment bottle (I marked the bottle in 2 oz intervals and add 1 oz per 10 gallons when refueling).
Well, this bottle (which I've been refilling with Lucas UCL from their bigger bottle) has been fine all this time with UCL. I washed the bottle out completely using Dawn dishwashing soap and made sure to rinse it out completely and let it dry before pouring FP Plus into it.
After refilling it a few times with FP Plus, this last time I've been trying a different fuel additive (while leaving the Lucas bottle with FP Plus in the car) and the bottle has shrunk the same way the large jugs of FP Plus have.
If I can find a very accurate scale, I'll try measuring to see if there is weight loss from leaving FP Plus in one of these bottles over a period of time.
Max
Well, this bottle (which I've been refilling with Lucas UCL from their bigger bottle) has been fine all this time with UCL. I washed the bottle out completely using Dawn dishwashing soap and made sure to rinse it out completely and let it dry before pouring FP Plus into it.
After refilling it a few times with FP Plus, this last time I've been trying a different fuel additive (while leaving the Lucas bottle with FP Plus in the car) and the bottle has shrunk the same way the large jugs of FP Plus have.
If I can find a very accurate scale, I'll try measuring to see if there is weight loss from leaving FP Plus in one of these bottles over a period of time.
Max