Do HST filters have Bypasses?

[RickB]

Maybe so, but are you saying that filters assembly's that have bypass valves inside the filter , have no bypass valves in the filter housing?

I posted nothing either way regarding bypass valves in filter housings beyond calling you out for suggesting that the filter bypass is located in the filter housing, which I took to mean the filter head. Your post allowed for no exceptions and therefore is false and does no service to the poor guy trying to match filters. Neither you nor I have a clue as to whether a Deutz-Allis 5220 has hydraulic and/or hydrostatic filter bypass mechanisms or where they may be located. A proper filter cross-reference will include an element with the proper bypass valve if one is required. That's all the OP is looking for.

Wix lists a hydraulic cartridge filter #51257 and #15250 housing o-ring for a 5220 HST. They have no listing for the hydrostatic filter. This means that probably NAPA and CarQuest can get that filter, as Wix supplies both retailers. Baldwin lists no hydraulic system filters for a 5220. Fleetguard only lists an outer air filter. The OP is probably going to have to pony up for OEM filters.

 

[J_J]

Correction to my last.

Q: Do hydraulic filters have bypass valves?
A: Hydraulic filter bypass valves if present are typically located in the filter head assembly or a separate component to the hydraulic system.

 

[racerboy832]

Oh boy, I hope I didn't start a fight over a simple ?. My Question was, Do HST Filters (Not regular Hydraulic filters) have a bypass in them. I've looked up everysize 1-1/8 X 16 filter I can find. The one that is made by Wix that is a dead ringer physically to what is on my machine does not have a bypass setting. The one I took off my Machine Does not appear to have a bypass. If the HST filter mount has some sort of bypass in it then this filter I looked up in theory should be fine. If you told me that HST filters have bypass in them 99% of the time they i'd say, oh shoot I guess I better keep looking for other filters. I'm just playing process of elimination before I try the Wix filters. If the OEM Filters weren't $100 each I would just buy them. The dealer doesn't even know if he can find them both since it shows one as a cartridge and mine both are spin ons.

 

[Chilly807]

The actual system oil pressure has little effect on the bypass mechanism, it could be 200 psi and still not open a 15 psi bypass. The bypass is designed to work on differential oil pressure, i.e. if the pressures before and after the filter differ by more than a set value (15 psi for example), the bypass will open and allow at least some flow past the valve.

The thinking is that if the filter is starting to restrict oil flow enough to reduce the pressure by an appreciable amount, it is dirty. A lot of heavy diesels have two oil pressure gauges, one before the filter and one after. The operator can see easily how much restriction is in the oil filter. Some have idiot lights based on oil pressure differential values.

Sean