Fleetguard LF777 Oil Filter B7577 1W-8845 1W8845 9Y-4468 OC282

What is the LF777 filter used for?

BOMAG  K 401
BUCYRUS  RH 120 ERH 120 E
CATERPILLAR  245 D3176 B 3NL1->3176 B 9CK1->34006030 FS6030 FS924 F962 GC 10
CHALLENGER  1603 1664 1903 2505 9103 9203 9205TG 3244TG 9300
CLARK  125 C175 B175 C275 C280 C475 C475 C55 B55 C75 CL 190 BL 270 BL 320L 480 B
COMPAIR-HOLMAN  650-170 S750-170 S
CTM  GENERATING SET 1600 KVA

CUMMINS  K 1150K 19K 38K 50KT 1150KT 1150 MKT 19KT 19 MKT 2300KT 2300 MKT 38KT 38 MKTA 1150KTA 1150 MKTA 19KTA 19 DM 1KTA 19 MKTA 2300KTA 2300 MKTA 3067KTA 3067 MKTA 38-G3KTA 38 MKTA 38 M-1KTA 38 M-2KTA 50-G3KTA 50-G4KTA 50 MKTA 50 M-1KTA 50 M-2KTTA 38KTTA 50L 10L SERIESLT 10 CN 855 CCECNT 855NT 855 MNTA 855 MQSK 19QST 30V 28V 28 MV 555V 903VT 555VT 555VT 903VTA 28 G3VTA 28 G5VTA 28 M
CUMMINS POWER GENERATION  C 1250 D2RGRPE ELECT VTA 28-G3
DETROIT  60 SERIES
DOOSAN DAEWOO  MEGA 300 VMEGA 400 VSOLAR 330 V LC

Premium Fleetguard LF777 Oil Filter B7577 1W-8845 1W8845 9Y-4468 OC282

Q: What are the features of the LF777?

LF777 is a Fleetguard By-Pass Oil Filter, a spin-on filter for heavy-duty engines using StrataPore media for deep filtration and longer oil change intervals, protecting components by filtering fine particles from the lube oil.

Q: What is the difference between the LF777 and other filters?

LF777 is a bypass oil filter under the FLEETGUARD brand, differing from other filters mainly in its working principle, filtration accuracy, and application scenarios.

The core difference between LF777 and other filters is as follows:

1. ‌Different working principles: bypass type vs. full flow type‌
   LF777 is a bypass filter element. It filters only a small portion (about 10%) of the engine oil, guiding it for deep and fine filtration to remove smaller impurities, achieving "fine filtration".
   Other common filters like LF670 are full flow filter cartridges. They filter all engine oil, ensuring all oil entering the engine is preliminarily filtered, but with relatively low accuracy, mainly used for "coarse filtration" to prevent large particle impurities from causing engine wear.

2. ‌Different filtering accuracies: Fine filtering vs. Rough filtering‌
   LF777, as a bypass filter element, has a higher filtration accuracy, effectively capturing smaller particles and deeply purifying engine oil to help extend engine life.
   LF670 and other full flow filters have lower accuracy, targeting larger particles and serving as the first line of defense.

3. ‌Different application scenarios and functions: deep purification vs. basic protection‌
   LF777 is typically used as an auxiliary filter with full flow filters (like LF670). It supplements them to provide higher oil cleanliness, suitable for engines needing extreme cleanliness or extended oil change cycles.
   LF670 and other full flow filters are standard components, providing basic protection.

In summary, LF777 is a high-precision bypass fine filter, while LF670 is a basic full flow coarse filter. They complement each other, with LF777 working alongside full flow filters for better engine protection.

Q: What is the purpose of the bypass oil filter?

The bypass valve is a critical safety component in the oil filter, primarily designed to ensure continuous engine lubrication under special conditions, preventing severe wear caused by lubrication interruption.

The specific functions are as follows:
• Protect the engine during cold starts: In cold environments, the viscosity of engine oil increases significantly, reducing its fluidity. If the oil cannot pass through the filter promptly, engine components may suffer dry friction damage. The bypass valve opens, allowing unfiltered oil to flow directly into the engine, ensuring rapid lubrication.
• Maintain oil supply when the filter is clogged: As the oil filter gradually accumulates impurities during use, the bypass valve opens when excessive resistance to oil flow occurs, allowing oil to bypass the clogged filter element. This maintains normal oil pressure and ensures the engine operates properly.

• Bypass valve activation mechanism: The opening pressure of the bypass valve is set by the manufacturer, typically ranging between 0.8 bar and 2.5 bar, with variations across different vehicle series (e.g., around 1 bar for Japanese cars, approximately 1.5 bar for American cars, and about 2 bar for European cars). This pressure value is precisely designed and cannot be adjusted arbitrarily by users.

It should be noted that when the bypass valve is open, unfiltered engine oil may introduce contaminants into the engine, increasing the risk of internal wear. Therefore, regular oil and oil filter replacements are crucial to reduce the frequency of bypass valve activation and ensure the engine remains well-lubricated over time.