EVAP Smoke Machine Questions – OTC 6521 LeakTamer

Below are a couple of recent questions about the OTC LeakTamer Smoke machine.
Q: We are getting a lot of Evaporative codes in our shop lately. Is the OTC 6521 LeakTamer easy to use?

A: Absolutely, it is. It is portable and is basically used the same way on every vehicle. Find a place to hook up the hose and you’re off and running.

Q: Why is it recommended to use Nitrogen instead of shop air? I’ve seen smoke machines that are cheaper that don’t use Nitrogen, so why use Nitrogen?

A: Using Nitrogen with a smoke machine when testing an Evaporative system is the only way to follow automaker test requirements for all makes and models. Most major car manufacturers require or recommend using Nitrogen. Under the heading of Hazard Prevention, SAE (Society of Automotive Engineers) Technical Paper 2007-01-1235 states, “Inside the confines of the fuel system,  flammable mixtures can be prevented by using nitrogen as the carrier gas for the leak detection fluid instead of air.” Shop Owners who are genuinely concerned about employee, customer vehicle, and shop safety use Nitrogen. It’s inert, non-flammable, and prevents a contaminated air supply from inadvertently reaching a customer’s vehicle.

Now with that being said, many repair shops don’t use Nitrogen – they simply use shop air from an air compressor.

Also I would be cautious when considering a cheap unit – besides the OTC 6521 LeakTamer is priced lower than I’ve ever seen it before right now!

Learn more about using a smoke machine.

OTC6521 Smoke Machine – Smoking Recommended

car smoke dollar 2

The OTC6521 smoke machine for EVAP testing is the best tool I’ve seen for checking trouble codes like P0440, P0442, P0455, P0456 and P0457 that can be caused by evaporative system leaks. Diagnosing an evaporative code is no fun without this tool. Leaks are the leading cause of EVAP codes, many times it’s just a loose gas cap. But if it’s not the fuel cap the OTC 6521 will provide a quick easy way to find the leak.

Other Uses

Vacuum leaks can also be traced easily with the OTC 6521 smoke machine. Engine codes for lean conditions like P0172 and P0174 are usually because of a vacuum leak. If the vacuum leak isn’t an obvious one, then a quick smoke test with the OTC6521 smoke machine will make finding it much easier. I remove a random vacuum line and block off the air intake hose, fill with smoke and see where it comes out.

The OTC 6521