Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Seals poorly !

I used this ONE time to remove oil from my van. When I went to use it just 3 days later on my other car, it would not extract transmission fluid.The plastic fitting that connects to the top of the unit was sucking air, so it would not create a vacuum. I had to stuff a circular piece of paper napkin between the fitting and the opening to get it to seal and work somewhat.After the first use the unit was rinsed with a mild solvent and cleaned as per the instructions. The oil I extracted from the van was NOT synthetic (see someone else's review on that subject). I now need to find the correct size O-ring to replace the defective,leaky original.The fitting should be of the threaded type and not a press fit that becomes leaky in a short time! Not much quality for $70+...