Baldwin Filters
Baldwin Filters PT91 Hydraulic Filter Element 7in
Hydraulic filter element with a 27 micron rating and reinforced centertube for Caterpillar equipment
- TypeAutomotive Filters
- 27-micron filtration protects hydraulic systems
- 7-inch cartridge fits Caterpillar equipment directly
- Reinforced centertube maintains structural integrity under pressure
- Cartridge element design simplifies routine maintenance
- 5 1/8-inch diameter ensures proper housing seal
Hydraulic Filter Element for Caterpillar Equipment
This Baldwin Filters PT91 cartridge is a hydraulic filter element designed for Caterpillar machinery. It carries a 27 micron rating and measures 7 in height by 7 in length with a 5 1/8 in outside diameter. The reinforced centertube adds structural strength during operation. It suits maintenance teams and equipment owners needing a direct-fit replacement element.
Replaces Worn Cartridge Elements
The element replaces a spent hydraulic cartridge when pressure differentials rise or scheduled service intervals arrive. A 27 micron rating captures particles that accelerate wear in pumps and valves. The jump is worth it when oil analysis shows contamination approaching the limit or when the current element has reached its rated service life. No thread size applies, so installation follows the housing manufacturer's procedure.
Check Housing Dimensions and Compatibility
Verify the housing accepts a cartridge 7 in tall with a 5 1/8 in outside diameter and a 3 3/8 in inside diameter before ordering. Confirm the equipment manufacturer specifies a 27 micron rating for the application. Ensure the reinforced centertube design matches the original element construction. Buyers who need a different micron rating or a spin-on style filter cannot use this element.
Highlights
- 27-micron filtration protects hydraulic systems
- 7-inch cartridge fits Caterpillar equipment directly
- Reinforced centertube maintains structural integrity under pressure
- Cartridge element design simplifies routine maintenance
- 5 1/8-inch diameter ensures proper housing seal
Specifications
| Brand | BALDWIN FILTERS |
|---|---|
| Type | Automotive Filters |
Questions about this item
What housing dimensions are required for the 7 in length and 5 1/8 in outside diameter cartridge?
The element measures 7 inches long with a 5 1/8 inch outside diameter and a 3 3/8 inch inside diameter, so the housing must accept those exact cartridge dimensions.
How is the cartridge installed without threads, and what step is often missed?
Slide the cartridge over the centre post until the reinforced centertube seats fully; the step often missed is verifying the seal seats evenly before pressurising the system.
When should the 27 micron hydraulic element be replaced?
Replace the element when the system differential gauge indicates the 27 micron filter has reached its dirt-holding limit or at the interval specified by the equipment manufacturer.
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