I just received my Grandmothers Singer Treadle. The owners manual says it is a 15-88 or 15-89. It is filthy as my sister had it for many years and stored it in the barn "shame on her". So I have a lot of work cut out for me. The cabinet itself is in pretty good shape but the machine is frozen up. There is tape on the Treadle Stand so I have a feeling it is cracked or broken. i have tri flow and pb buster do you think it is safe to use the pb blaster to get things moving again?