Tool Review: Bar’s Products AC-1 A/C Stop Leak and Sealer

Bar's Leaks developed the Professional DiFM AC-1 A/C Stop Leak and Sealer to permanently seal rubber and metal leaks. With a non-clogging formula, this solution is compatible with all types of automotive A/C refrigerant. The formula also contains A/C system UV dye for leak detection and special synthetic oil seal conditioners for o-rings and gaskets.

The review

Lou Fort, lead tech at K.A.R.S. in Huntingburg, Ind., and a veteran ASE-certified Master Tech, reported that Bar’s Leak AC-1 A/C Stop Leak and Sealer is easy to use and might be a real time-saver in situations that don’t warrant repair. He suggested it would be useful any time the refrigerant system is charged “as a sort of an insurance policy against a small seal or fitting leak causing a comeback.” That’s because it’s not like other A/C sealers he’s familiar with.

“A/C sealers have a lot of us scared to death (because) so many of them on the market are equipment killers. This is not (because) they don’t claim it will stop all leaks. In a system that is tested and proven to hold a specific amount of vacuum for a specific amount of time, they say it can seal a leak buy forming a non-hardening seal.”

Lou said the product was easy to use because it comes in pre-measured doses that also include a tracer dye. He feels that the dye is a further indication of the product’s less aggressive sealant. “They don’t claim it to be a cure-all, so if your leak is, say, a shaft seal, you already have the dye in the system to find the leak.”

He did suggest one improvement: a warning label that could be attached permanently somewhere under the hood. “I personally feel a true professional would want to let everyone know that a sealer/dye has been added to the system. It could even serve as advertisement for them.” He suggested the bottle be fitted with a peel-and-stick label.

Although he is comfortable using the sealer, Lou says the jury is still out on just how effective it can be. “Small A/C leaks can take months to actually show in a real world environment. I was wrong in my estimation of the number of times I would have a chance to experiment with this sealer this late in the year. I’ve used only four of the six bottles we received. One is on a 2001 Crown Vic that came in for a compressor failure. The Sealer/Dye was added (after repair) as an insurance policy. Another was a 1996 Deville that had a small evaporator core leak. When (the customer was) told it would be over $1,200 to install a core, they just couldn’t afford it. So after explaining this new product, they decided to give it a try. We should know in a few months if it has fixed that Deville.” Lou described a similar situation with a regular customer’s Dodge Dakota, saying that “time will tell the tale.”

So it’s too soon for Lou Fort to know if AC-1 A/C Stop Leak and Sealer will seal a known leak, but he considers it an inexpensive way to prevent comebacks on a proper A/C repair. Perhaps most importantly, because of the company’s claims (and the fact that it’s intended for use by professional technicians), he’s comfortable that it won’t cause problems with his recovery/recycling equipment.