Hello, I have been ordering engine oil & hydraulic oil filters from J-Thomas. I noticed that the oil filters look identical to the hydro filters & there is no distinguishing marks except for a sticker on the box. One batch of the hydro filters did look different than the oil filters (they were black & had more & smaller perforations to the filter paper), but all of last years order & in some of this years order, the filters looked identical. When I called J-Thomas, the order taker checked something & told me the filters were interchangeable. I informed her that the hydro filter were twice the price of the oil & asked why I was paying twice the price for identical filters. She put me over to a technician who said no she had made a mistake, they were not interchangeable...the hydro are supposed to be 10 micron. I decided to cut the filters open & here is what I found. Opinions please. The first pic show a Toro Hydro Filter...folowed by one of J-Thomas' Black hydro filters(same part# as the other hydro filters in the pic)...followed by three of the J-Thomas eXmark hydro filter...folowed byt hree J-Thomas engine oil filters. More pics to follow
The third is a Toro OEM hydro filter next to a J-Thomas hydro. The paper on the Toro is noticably thicker.
The fourth pic shows a J-Thomas hydo filter next to another J-Thomas hydro filter-The part #'s are the same. The one on the left is the black filter...the j_thomas technician told me they are sometimes black & sometimes white, depending on supplier. The black one does have the thicker paper...remember it's the same part #.
I will be from now on. Here what the filters look like from the outside. No distinguishing marks except a sticker on the box & twice the price for one over the other.
Your presentation doesn't really prove or disprove anything. All it does is maintain the fact that not all filters are built the same. With hydro filters the two most important things are filtered micron size and filter area. Hydro pumps are built with clearences that will allow certain sized particles of metal, dirt or whatever to pass through the system without hurting it. The filter must also allow a certain amount of fluid to pass through the media at a certain vacuum or else you can collapse the supply hoses. Once the supply of oil is reduced or cut off it can be only seconds before serious damage occurs. This is also why it is important to change the filters at the recommended intervals. BTW, most hydro filters do not have a bypass valve. The size of the filter media and even the way it is pleated is very important too. If your media is too small the filter can plug up before the recommended change intervals. If the media is too big it can cause the manufacturer to put too many pleats in the media so it will fit inside of the canister. If the pleats are too close together they can close off the media at the inside of the filter rendering that filter area useless. I buy Dixie Chopper hydro filters for my Dixie. You only change them once a year and mine cost $15 a piece.
Richard, look at the second pic...that filter paper, pleating etc. is identical & yet they are sold as hydro & engine @ different prices. The OEM has thicker paper. Isn't the 10 micron hydro filter supposed to have thicker paper...& not be identical to the engine oil filter?
