A/C leak... anyone use those leak-enders in a can?? - PeachParts Mercedes-Benz Forum

infinite007 · #1 07-23-2003, 11:18 AM

anyone have any experience with those leak plugger uppers in a can? anyone see any downsides to this product: ie damage to a/c components, etc? The leak is in the evap coils of my 1994 benz. they gotta remove the whole dash and quoted around $4000.00 for the job. I smell ripoff... but I'm jus wondering if this stuff in the can actually works... or if i can potentially damage my A/C system. I hope not. ur thoughts greatly appreciated.

~manny

csnow · #2 07-23-2003, 11:27 AM

I would not risk it with the leak-stop.
Imagine if you ruin other components in the process, like clogging the condensor, or frying the compressor.
You could be out even bigger money.

Evap replacement is always a big job.
I did one last month (not on an MB), and it took me 2 long days on the driveway.
4k sounds high for a professional though. I had heard that 'book' time is in the 14 hour range for some MB models.
Too bad these things cannot be designed to pull out through the firewall (or simply last forever)!

Seems that r-134a systems are way more prone to evap failure than r-12 systems ever were. Not just an MB phenomenon. I hope the manufacturers are 'learning' something from this, and designing better evaporators. Maybe some of the recall-related costs will 'convince' them. Seems that they are good enough to outlive the warranty in most cases, however.

Best of luck.

#3 07-23-2003, 11:30 AM

1. These things rarely are effective.

2. If sealer is detected in system, auto a/c shop will not work on it because the sealer will destroy their multi thousand dollar recovery/recycle machine when it is recovered.

3. One is rarely successful in getting "something for nothing" which is what such products offer.

I know it's a hard pill to swallow, but buy an evaporator and change it yourself. There are several threads regarding the job. A fellow from Houston that I have met recently changed it and posted afterwards that you should not be afraid of the job.

Good luck,

jcyuhn · #4 07-23-2003, 01:29 PM

I have some firsthand and secondhand experience with these products. I've used both cryo-chem (http://www.cryochem.com) and keep-it-cool (http://www.keep-it-kool.com).

First, these products can be effective. In both cases they did an essentially perfect job of sealing the system for me. Anecdotally, they don't always work - I've read on various internet boards where some folks have had great success, others not much. Shoot, our own SteveBFL admitted his cheapskate business partner used it on a 140 chassis with surprising success. I'd guess (and this really is a guess) the success rate runs about 75%.

Second, these products are activated by moisture. The system must be extremely well dehydrated before installing them. This means changing the dryer and a very deep vacuum. If you can't pull a deep vacuum, they are not going to work satisfactorily. I personally prefer the cryochem solution; it's a two part solution which includes a drying agent. The sealer is added about 20 minutes after the dryer. Keep-it-cool is added all at once. Of course, cryochem is more expensive - $150 vs. $50.

I got lazy and didn't change the dryer one of the two times. Guess what - the sealer activated in the dryer, partially clogging it. Changing out the dryer followed by a thorough vacuum cured that problem. It isn't going to harm your compressor no matter what happens. It could clog the condenser, expansion valve, dryer, or evaporator. I just want to get through the Texas summer so I can replace the evaporator at my leisure later in the year.

AC shops hate this stuff, for two reasons. One is that it certainly robs them of revenue opportunities. The second is that it does occasionally activate in their recovery machines. But let me point out another side of that issue. The sealants are moisture activated. The only way they will trigger in a recovery machine is if the dryer in the recovery machine is saturated and beyond needing to be changed. Any AC shop with a "wet" recovery machine is pumping water into your system along with refrigerant, setting you up for an acid burnout down the road. I see a certain poetic justice in the whole thing.

My recommendations: 1) Only consider this if you do you own ac service work and won't be taking the car to a shop. 2) Changing the dryer, the markup on the sealant, etc. probably make it expensive enough that you should just go for the evaporator replacement if you have to hire it done. 3) Consider it a stopgap measure until you can fix it permanently. You'll still need to replace the vacuum flaps in the dash after using the sealant

Good luck,

- JimY

csnow · #5 07-23-2003, 02:29 PM

Moisture activated?
So what happens the next time the system is opened to the atmoshere? Does everything you are not replacing get clogged up? Can it be flushed?

jay3000 · #6 07-23-2003, 03:18 PM

About AC sealers..

http://www.motor.com/MAGAZINE/Pdf/042003_04.pdf

wjm · #7 07-23-2003, 04:50 PM

infinite007,

AllData calls for 13.7 hours for the job on my 94 E420. This does Not Include: Refrigerant Recovery Or Evacuate & Recharge AC System. Includes: R&R Heater Housing Assembly.

Still, 13.7 * $75 = 1027.50.

See if you can find a service location that quotes using alldata and find out what their $/hr take is.

JimF · #8 07-23-2003, 05:27 PM

commerical brand called, Leak Sealer Pro made by ClipLight. Check my page (click 'www' icon below) and select Menu #16.
My evaporator had a small leak (?) and it did fix it.

Of course, there are many cons for not using it!. Buy when the cost of the repair starts to approach the value of the car, I think that would be a reasonable reason to use it.

But it should be done carefully and not hap-hazardly. The articles in the previous threads give all of the facts that should be considered before it's use.

jcyuhn · #9 07-23-2003, 06:11 PM

Yeah, moisture activated. Leaking refrigerant cools the area where the leak is located, causing condensation from the surrounding air. The condensation activates the epoxy in the sealer, plugging the leak. At least in theory.

Short exposure to atmospheric isn't a problem. I changed out the dryer in my car while at least some of this stuff was in there, so the system was exposed for perhaps an hour. It's been three months since then with no problems.

The sealer circulates with the oil in the system. So flushing the system removes the sealer.

It's not a panacea, but if you can't afford or can't find someone competent to tear apart the car replacing the evaporator, it's an alternative.

From an economic (and definately not environmental!) analysis, I think the sealer almost always wins. If the sealer slows the leak to where the car consumes, say, $50 of refrigerant per year, you will never recover the cost of replacing the evaporator over the remaining life of the car.

- JimY

infinite007 · #10 07-24-2003, 04:14 AM

Thanks for the replies!!!

Well... My dad is an A/C tech....owns his own business. He does A/C for homes and businesses, not cars. After talking with him just recently, he strongly advised against me using this stuff. He would rather just bring the car to have the evap changed than to have the whole A/C system changed because of using this. The leak is kinda big. It used to take 3 weeks for the refrigerant to escape, but now it takes 1 day.

We checked all the exterior portions of the system hoping that it was something outside, easily accessible, rather than inside (behind the dash)...no leaks. I posted a while back about this. Many responded that the W202 evap was NOT likely the culprit. But... I guess my luck ran out!!!

I found someone who'd do this for about 1.5k-1.8k. I think I'll be bringing the car in next week or so. I'd do it myself... but dont have the tools or the instructions to remove the dash. anyone have those? I've been using the search to find that and came up unsuccessful.

anyway, thankss!!!

~Manny

jcyuhn · #11 07-24-2003, 10:08 AM

I've never heard of a 1-day evaporator leak. Are you sure there's not a broken o-ring, or something simple like that? A leak that big can usually be found by sound (just listen for the hissing) or by a soap & water solution (look for the bubbles).

At any rate, a sealer isn't going to work on a 1-day leak, so you don't really have any choice but to find the problem and replace/repair the faulty component.

- JimY

infinite007 · #12 07-24-2003, 10:50 AM

Jim...

did that already. The soap/water thing... electronic leak detector...fluorescent dye... all negatori on the outside components.

I figured that the leakstop thing wouldnt work once that leak got that big. grrr... oh well. gotta shell out the big bucks! thanks fo u'r help tho!!!

~manny