Sampling Oil Using a Drain Plug

The following is a sampling procedure for oil sumps/ reservoirs, without fixed sampling hardware installed and where dipstick or fill-cap access is unavailable.

The oil sample is collected by gravity drain into a sample jar.

Procedure

1. Take sample under normal operating conditions when possible or immediately after shutting unit down. That will ensure a homogeneous sample of hot flowing oil.
2. Wipe excess contamination from sample area.
3. If sampling from the drain plug, remove drain plug and place it on a clean cloth to prevent contamination. Let sufficient oil drain out before taking sample.If system has drain pipe, flush 5 times the volume of the dead leg before taking sample.
4. Avoid overfilling the sample jar. Fill sample jar to or above the fill line but below the threads of the jar. Seal the jar tightly, wipe clean.
5. Pre-label or label sample jar immediately after filling to avoid mix-ups. Make sure jars are labelled with full sample details (i.e. unit number, component type, date, kilometers/service hours on unit/component/oil, oil type and grade, repairs/service during drain interval, oil changed Y/N).
6. Ship the sample to the appropriate Fluid Life location. Do not stockpile samples for shipping.

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