A borescope works by inserting its probe into the inspection area, then using the screen or eyepiece to see what’s inside—steering the tip for a full view.
The core routine is the same across most models: power on, check the lens, insert the probe, adjust light and focus, then steer for a complete picture. The steps below walk through the process for video borescopes, mechanical units, and the common mistakes that trip up first-time users.
Before You Start: Two Quick Checks
Set yourself up for a clean first inspection before the probe goes anywhere near the engine block or wall cavity.
- Insert the SD card first. ViewTech’s VJ-3 manual is specific: put the SD card in before powering on the unit. Image capture and video recording simply won’t work without it, and some units won’t boot properly if you add the card afterward.
- Wipe the lens. A smudged lens makes the whole inspection useless. On articulated models, clean carefully without flexing the bending section while you wipe—that’s the fragile part.
- Keep the insertion tube straight at startup. Bending the tube before you begin can stress the internal cabling and affects how the tip steers later.
Using a Video Borescope: Step by Step
Video borescopes are the most common type for automotive and home use, and the procedure is nearly identical across brands.
Power on and format the card. Press and hold the power button; on the PCE-VE 200, that’s a two-second hold to switch on or off, and the unit prompts you to format a new micro SD card before first use. Milwaukee’s 3150-20 uses the same press-and-hold pattern. If you’re using a new card, format it in the borescope itself rather than in a computer—the file system needs to match what the unit expects.
Insert and steer. Slide the probe into the inspection area slowly, keeping the tube as straight as practical on the way in. On models with an articulating tip, the joystick or wheel on the handle steers the camera. ViewTech’s manual notes that you should adjust brightness after insertion—what looks right in open air is usually too bright inside a dark cavity.
Capture what you see. The photo and video buttons sit on the handle on most units. PCE’s manual shows dedicated buttons: one for pictures, one to start and stop recording. When you’re done, pull the probe out straight, power down, and remove the card to transfer files.
Using a Mechanical Borescope: A Different Skill
Mechanical borescopes have no screen—you look through an eyepiece, which changes the workflow entirely.
Focus the eyepiece first, then connect the light guide to a compatible light source. Everest’s manual for its rigid borescope is specific: it connects to an ACMI light guide and a compatible source like an Everest VIT. Before inserting, check for a bright light at the tip; if the tip is dark, nothing downstream will be visible. Verify image sharpness on a known surface, then insert the shaft slowly, rotating it as needed to sweep the viewing angle across the full interior.
The trade-off is clarity versus reach. Mechanical units deliver crisp, distortion-free images, but you give up the convenience of a handheld screen and photo capture.
Common Mistakes and Practical Tips
Most failed inspections come from a handful of avoidable errors. Here’s what to watch for, summarized in the table below.
| Mistake | Why It Hurts | The Fix |
|---|---|---|
| Skipping the SD card | Photo and video won’t record | Insert before powering on |
| Too much brightness | Washes out the image in tight spaces | Adjust after insertion |
| Flexing the bending section while cleaning | Damages internal cabling | Wipe gently, keep it straight |
| Using a low-grade SD card | Write errors and dropped footage | |
| Pushing the probe past resistance | Kinks the tube or damages the target | Back out, adjust angle, reinsert |
Match the SD card to the job. PCE specifies a C4 micro SD card or above—that speed class matters for recording video without corruption. A card that lags will drop frames even when it appears to record fine.
Keep the tube straight going in. If you meet resistance, don’t force it. Back out a few inches, rotate the tip, and try a different angle. Forcing the probe is how tips get bent and cavities get scratched. And when you’re inspecting deeper, work in passes rather than one long slide—go in, look around, come out, adjust, repeat.
If you’re choosing a model for automotive work, a dedicated mechanics borescope with a steerable tip and decent light output makes the difference between a quick look and a frustrating afternoon. Our roundup of the best borescopes for mechanics covers which models handle the tight spaces and tough angles you’ll actually face.
FAQs
Do I need to format the SD card before every use?
No—only when the card is new or has been used in another device. Formatting wipes the card, so don’t do it before every session if you want to keep your previous inspection photos and videos. If the borescope prompts you to format, that’s the signal it can’t read the current file system.
Can I use a borescope to inspect the inside of an engine?
Yes. You’ll need a model with a probe slim enough to fit through the spark plug hole or intake port, plus a steerable tip to look around cylinders and valves. A bright LED light is essential, since there’s no ambient light inside an engine. Many automotive-specific borescopes include these features as standard.
Why is my borescope screen showing a black image?
The most common cause is insufficient light reaching the camera. Crank up the LED brightness, and if your model has it, check that the light ring or fiber bundle at the tip isn’t blocked by debris or a smudged lens. On mechanical units, verify the light guide is firmly connected to the light source.
References & Sources
- ViewTech. “VJ-3 / VJ-3A Borescope Manual.” Details SD card insertion, straight-tube handling, and joystick steering.
- PCE Instruments. “PCE-VE 200 Operating Manual.” Covers power-on sequence, card formatting, and photo/video buttons.
- Everest VIT. “Rigid Borescope User Guide.” Explains eyepiece focusing, light guide connection, and shaft rotation technique.