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Oil Sight Glasses

The Oil Sight Glass product line consists of the original Oil Sight Glass, the Oil Sight Glass & Level Monitor,  the Oil Level Indicator and the 3-D BullsEye. Our products provide lubrication management professionals a complete and immediate visual oil analysis.

The Oil Sight Glass is a clear acrylic cylinder that installs in the drain port of the oil reservoir of pumps, gearboxes, bearing housings and other lubrication-critical pieces of equipment. It provides continuous fluid monitoring of clarity, color, sediment, and water contamination. The drain valve allows for discharge of accumulated water. These products enable personnel in many industries to constantly manage the condition of their oil.

The Esco Oil Sight Glass

The original Esco Oil Sight Glass handles most applications. The Esco Oil Sight Glass (OSG) is the model that started the product line over 30 years ago. Water wreaks havoc on lubrication systems, causing premature wear. With the OSG, users have an immediate visual inspection of the oil and the ability to drain any accumulated water.

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The OSG is installed directly to the a drain ports located on the side of the equipment. The spring loaded drain valve is utilized to drain off any water contamination. Any sediment or particles in the lubricating fluid will matriculate to the OSG where, upon inspection, the user can determine the appropriate action. The Oil Sight Glass is effective in most operating environments with the maximum temperature rating of 230 F and maximum pressure rating of 265#. (Operating Temperatures and Pressures: 180 F to 265 PSI, 203 F to 66 PSI, 230 F at atmospheric pressure)

Horizontal Esco Oil Sight Glass

Horizontal Style when access is limited. The Horizontal Mounted Oil Sight Glass provides continuous fluid monitoring of the clarity, color, sediment and water contamination by allowing operators the ability to see the oil, monitor its condition and instantly drain the water accumulation. Designed for equipment that is located to close to the ground to install the Standard Oil Sight Glass, the Horizontal Oil Sight Glass solves the problem of limited access. 

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Minimum ground clearance is typical for many gear boxes. This problem is solved by the eccentric placement of the inlet nipple and outlet drain valve to allow for the same efficient functionality of the Oil Sight Glass but in a horizontal position. The strong, crystal clear, cast acrylic, brass nipple and drain valve are suitable for most environments, but stainless steel hardware is available. When the Tattle Tales, Bottom Sediment and Water Bowls, BS&W, Pig Tails or Bulls Eyes cannot do the trick because of limited vertical access, this product is your answer. The Horizontal Oil Sight Glass is effective in most operating environments with the maximum temperature rating of 230 F and the maximum pressure rating of 265#.(Operating Temperatures and Pressures: 180 F to 265 PSI, 203 F to 66 PSI, 230 F at atmospheric pressure)

Oil Sight Glass & Level Monitor

When properly installed at the oil reservoir drain port, the Oil Sight Glass & Level Monitor allows the user to view the oil color, clarity, and accumulation of water or other contaminates. The strong, clear cast acrylic body allows for viewing of the level. The spring loaded drain valve is positioned to quickly discharge any water before it damages the oil lubricity.

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Red and green Buno O-rings are included with the OSGL to mark upper and lower limits, or to designate running oil level and idle oil level. Each Oil Sight Glass & Level Monitor comes with a 2-micron breather, which allows the oil level to equalize with the level inside the system. If you require a closed loop system, install the OSGL without the breather and use the top opening to port back into your equipment.

The height of the upper column comes in heights from 3″ to 24″ to correspond to the distance from the oil reservoir access port and the maximum height the oil will reach. Custom sizes are available. A Dual Port Oil Sight Glass & Level Monitor version is available with a second 3/8″ NPT port opposite the installation nipple to allow the installation of the Sample Port of oil sampling. The Oil Sight Glass and Level Monitor is effective in most operating environments with the maximum temperature rating of 230 F and the maximum pressure rating of 265#. (Operating Temperatures and Pressures: 180 F to 265 PSI, 203 F to 66 PSI, 230 F at atmospheric pressure)

3-D BullsEye

A better alternative to sight windows on oil reservoirs. Esco has developed a product to make the job of a lubrication technician or maintenance manager easier. The standard sight windows on oil reservoirs make it difficult to view the oil level, stain easily, and must be replaced often. Our team at Esco has improved upon the old-fashion sight plug with the creation of a replacement sight window called the 3-D BullsEye.

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The 3-D BullsEye is a clear cylinder made from one solid piece of acrylic with threading on one end and a rounded polished end for easier viewing of the oil on the other. Easily installed by wrapping the threads with Teflon tape, the 3-D BullsEye provides constant oil monitoring from any angle. 

The Esco 3-D BullsEye is effective in most operating environments with the maximum temperature rating of 230 F and the maximum pressure rating of 300#. (Operating Temperatures and Pressures: 180 F to 265 PSI, 203 F to 66 PSI, 230 F at atmospheric pressure)

High Temperature Oil Sight Glass

High Temperature style when the operation is hot. The High Temperature Oil Sight Glass is your answer when radiant heat from nearby equipment or unusually high operating temperatures exceed the safe use of the Legacy Oil Sight Glasses. Only available in Vertical Style, the Pyrex Glass and Teflon End Caps allow for operating the environmental temperatures up to 450 degrees Fahrenheit. So even under extreme temperature conditions, you will still be able to visually monitor the oil qualities and expel water contamination.

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This enhanced product continues to provide the visual oil management benefits when the Tattle Tale, Bottom Sediment and Water Bowl, BS&W, Pig Tail or Bulls Eye fail to operate due to high temperatures. The High Temperature Oil Sight Glass is effective in most operating environments with the maximum temperature rating of 450 F and the maximum pressure rating at 200 PSI.

Large Volume Oil Sight Glass

Large volume sizes for special applications. Most Tattle Tales, Bottom Sediment and water Bowls, BS&W, Pig Tails and Bulls Eyes fail to provide the necessary volume when high water volume water accumulation is a problem. When reservoirs or equipment produce so much water such that other products cannot hold it all between maintenance checks, the Large Volume Oil Sight Glass provides the extra storage to keep water out of the oil until it can be drained.

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Commonly used on large oil reservoirs, or on equipment operated in environments with regular high pressure wash downs and high condensation problems, where water contamination cannot be avoided or minimized, the added volumes of this line of products provides continuous fluid monitoring of the clarity, color, sediment and water contamination by allowing operators the ability to see your oil,  monitor it and drain the water accumulation as soon as it appears for equipment, while having the added advantage of storing more water accumulations between service or monitoring intervals. *Operating Temperatures and Pressures: 180 F to 265 PSI, 203 F to 66 PSI, 230 F at atmospheric pressure.

Oil Level Indicator (OLI)

The Oil Level Indicator (OLI) was developed in response to the need of maintenance professionals to gauge the oil level inside large tanks, gearboxes and reservoirs. When water contamination is not a problem or when a regular Esco Oil Sight Glass is already installed at the drain port, the Oil Level Indicator can be utilized to monitor oil level.

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The OLI is a clear acrylic tube with 1/2″ NPT threads at each end. Red and green Buno O-rings are included with the OLI to mark upper and lower limits, or to designate running oil level and idle oil level. It can be installed with the optional breather* at the top 1/2″ NPT port as seen on the Esco Oil Sight Glass and Level Monitor. If the user requires a closed looper, the 1/2″ MPT can be used as a connector port to feed back into the system. Operators can visually monitor the oil for dirt and debris and take appropriate preventive action.

Oil Sight Glass Options

Boss 245 Anaerobic Hydraulic/Pneumatic Sealant Option. After extensive research and testing, Esco Products concluded that Boss 245 is the ideal thread sealant to recommend with our Visual Oil Analysis Product Line. BOSS 245 Anaerobic Hydraulic/Pneumatic Sealant is a single component anaerobic thread locking adhesive.

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It is a purple liquid which cures between close fitting metal parts in the absence of air. The fast cure time, strong bond and easy application makes the BOSS 245 ideal for use with Esco’s Acrylic Visual Oil Analysis Products.

BOSS 245 Product Data  Sheet

BOSS 245 Uses and Properties

BOSS 245 MSDS

Magnet Drain Valve Option

The strong pull from this rare earth magnet will attract and hold microscopic ferrous particles. Further analysis of these particles can help determine what component is failing for replacement. The Magnet Drain Valve is easily interchanged with the standard drain valve on any Esco Oil Sight Glass Product.

Stainless Steel Hardware Option

All Esco Oil Sight Glass products are fitted with brass hardware which will provide excellent performance for most applications; however, 304 stainless steel hardware is available for environments that cannot accept brass.