Whitetiger777

iTrader: (1)

I'm going to replace my leaky compressor and condenser and figured it would be a good time to make the R134 conversion. Also going to get a new dryer, but I've heard some of the ones out there don't fit right. so I guess I have two questions.

1) Which PAG oil should I get? 100? 150????

2) Where can I get a dryer you all know will work? Or which brand? Or better if I could get one that is powder coated a different color.

j9fd3s

iTrader: (3)

Mazda has two dryers for the Denso A/C system, so you know i will fit, FD15-61-500. its not cheap, $202 list price.

the Mana dryer doesn't say NLA, but they don't have any and there is no price...

Whitetiger777

iTrader: (1)

$202??? Everyone seems to think they're around $20 to $30, or is that strictly for an after market item price.

DaleClark

iTrader: (55)

The Nippondenso driers are available CHEAP in the aftermarket, I got one at a local O'Reilly's for $30 or so and they had it in stock.

MANA driers are GONE. No aftermarket, no nothing.

Read up before you do 134a, the AC won't cool as well with it. Either do real R12 which is still available or do ES-12 or something like that. Do some research, there's plenty on the topic.

Dale

Whitetiger777

iTrader: (1)

The problem is when doing research on something like this I get mixed information. There are those who swear that if you empty the system and change the oil then the R134 will make no difference. There are those that say it will make a difference but not by much and those that say R134 will suck in any temp over 90 degrees outside. Some say that it is due to people not doing the conversion correctly, some say it just sucks no matter what. So you can see where it leaves most readers unsure since there are a lot of opinions. The other problem is, as I'm sure you know, that there are those who have not attempted the conversion, but because they read it on an other post that it doesn't work, they post the same belief but have no personal experience. This makes things difficult because a reader is never sure if he is getting the information from the source or a rehash. If someone did an improper conversion, posted how it didn't work, then you get a 100 or so people just saying it doesn't work not because they did it but because they read a thread, then things get convoluted.

Now don't get me wrong, I'm not saying you are one of those people, but since I've been doing research on this for a few weeks now I've gotten so many mixed reviews I don't know whats real. I figure it's easier to try and convert to R134 and if it doesn't work I reflush the system and switch back to R12 and I'm only out the few dollars on the nozzles, oil and R134 (which is cheap).

The ES-12a seems pretty cool...no pun intended. No one has brought it up to me yet, do I have to do any conversions to the 12a system, or can I just add it as is?

Oh damn, did I just read that ES-12a is a flammable refrigerant??? Won't that be a problem with hot hot things get under our hoods?

Oh, found this:
Enviro-Safe™ Refrigerant is flammable to an open flame but has an autoignition temperature of 1,585F (which is 1000F higher than that of 134a)! It is rated as a Flammable Gas. Flammable products are used every day within the household, business and in automobiles. Hair Spray = Flammable 3, Gasoline = Flammable 4, Propane = Flammable 4. Enviro-Safe™ Refrigerant = Flammable 2 and can be used safely in automobiles just like other flammable automotive products required for vehicle operation. All flammable products require your respect, adequate precaution and safe use practices. Follow all directions on the can or label and use basic common sense :-)

JM1FD

iTrader: (1)

In the official Mazda R-134a conversion documentation, Mazda said that the R-12 MANA systems were not suitable for conversion due to the low fin density of the condenser. The Nippondenso systems all had a higher fin density, and so Mazda deemed them suitable for conversion.

ACTUAL EXPERIENCE: A year or two ago, I helped a local forum member put a 1993 Nippondenso system on his car. We flushed all the components, put in 6 (?) oz of ISO 100 DEC PAG, and then fiddled around with the charge until the system "seemed happy". Charging was tricky because he has a front mount, and that was causing condenser temperatures (and pressures) to go way up. He is pleased with the performance of the system here in Houston. I think part of the reason that performance is acceptable is because we flushed the components and got the old oil out of everything. Too much oil will impede heat transfer, and probably causes many conversions to be sub-par.

ACTUAL EXPERIENCE II: Helped another local forum member get his system back up and running. He has a (mostly) MANA system with a Nippondenso drier spliced in. Flushed all the components and went back with mineral oil (not ND-7 oil) and R-12. Performance was good, but not as good as my unmolested R-12 system. I didn't have the necessary tools at the time to check the superheat, but I suspect the expansion valve we used is the culprit. It wasn't an exact fit (sensing bulb was too long) so I suspect either its superheat is not the same as what Mazda specified, or the bulb isn't getting a good "reading" and is underfeeding the evaporator.

My car will always be R-12. I just bought a small stockpile of R-12 for $12.50 a can off Craigslist. That's the same or less than what I would pay for R-134a at the auto parts store. At that price, and a system capacity of 2 cans or less, it makes ZERO sense to go R-134a.

XLR8

iTrader: (52)

ES-12 here. Stuff is awesome! There is a big thread on it.

Whitetiger777

iTrader: (1)

Thank you. Very good write up with facts not opinions, its very helpful.

Whitetiger777

iTrader: (1)

Ordered up ES-12a yesterday, from what I read it seems like a good deal. Direct swap over without having to change out the oil. I'll post my opinion of it once it gets here ans is used.

JM1FD

iTrader: (1)

I've felt the output of a 1993 MANA system running BBQ Gas. Rather inferior to what my car puts out running R-12.

I added some BBQ Gas to a 1993 Nippondenso system that already had BBQ Gas in it. The pressures were way off what they should be, and it sounded like the compressor started slugging liquid refrigerant (fortunately it has a bypass valve) after adding some more BBQ Gas. Impossible to tell what the correct charge level is, since the sight glass was all foam, all the time, and the pressures were screwy, and I'm not sure I trust the bottler's conversion data.

Also, the oil that the R-12 systems use is an oddball known as ND-7. I'm told it is neither a POE nor a PAG but a polypropyl glycolalkylene, so who knows if you'll get good miscibility and oil return or not.

Frankly, I don't understand the appeal of using flammable refrigerants in these cars when the system only needs 2 cans of refrigerant.

If it was a 1962 Buick that gobbled up 5 pounds of refrigerant with a compressor shaft seal where leakage is acceptable, and a tube and fin condenser then I could see the appeal....

Speed of light

iTrader: (8)

For the FD mana system use 2 full cans of ES12 (or ES-i12a preferably), and be sure to do a proper evacuation of the system prior to charging. Many problems (as mentioned above) can arise from having air trapped in the system, overcharging the refrigerant and/or overcharging it with oil.

I also have a NOS reserve of R12--yet I still choose--read: prefer to run the ES-i12a in my FD's mana system. Properly installed, it cools just as well as R12; however, it uses much less power to do so--reducing the loading on the engine to the point that it's not really noticeable; a significant benefit that I appreciate as much as the cold air.

Just to clear the air, so to speak, R290 and R600a, the two components of ES12, are legitimate refrigerants. Referring to ES (or any HC refrigerant) as 'BBQ gas' only serves to misinform. Furthermore, the scare tactic of flammability is a ridiculous argument in this context and is moot as there is little oxygen in any properly evacuated refrigeration system.

As to the oil, I put at least 100,000 miles on one FD compressor using the stock ND7 oil and with ES12 in the system. Never had any problems, so I must conclude that the miscibility is sufficient in this instance. I also know from experience that hydrocarbon refrigerants, e.g., ES12, work fine with mineral oil and Ester oils (POE's). One word of caution: It is important to have a proper charge of oil in the system. DO NOT overcharge the system with oil! DO NOT arbitrarily add oil as it can lead to lots of unexplained weirdness.

Another point worth mentioning about ES12 et.al., and other HC type refrigerants is that they are actually more miscible with most oils than many other refrigerants including R12. As a result, system oil will often be substantially redistributed following a conversion to ES12; sometimes, during this process, this will result in oil pooled up in some part of the system or backed up front of the expansion valve or orfice tube and it will take some run-in time to clear before reaching full cooling capacity and for system pressures to read normally--so do give it a chance to properly run-in.

And finally, if you don't like the ES12 you can always remove it and easily put R12 back in with no other changes (as long as you've stuck with stock ND7 or mineral oil). Whatever you do, don't put R134 in your system--you will be disappointed--R134a is an especially poor and problematic refrigerant for conversion systems. Period.

JM1FD

iTrader: (1)

I'm confused. Am I supposed to properly evacuate or sorta kinda evacuate if I want to. ENVIRO-SAFE says I can kinda sorta evacuate if I want to: "If desired, pull a vacuum. After pulling a vacuum of no more than 10 inches, do not charge under vacuum. ENVIRO-SAFE does not become caustic if some moisture is present. Charging under a high vacuum can result in an overcharge. Any overcharge may cause loss of cooling efficiency."

R-290 is Propane (You know, the gas that powers BBQ grills!)
R-600a is Isobutane

So...this stuff reduces horsepower use, cools great, the GWP and ODP are nil. Fuel economy is a big thing these days, so that horsepower reduction must have all the major OEMs all over this stuff, and they've been using it for years, right?

No? No major automakers have put this in cars?!? Wonder why.... Probably a conspiracy.

RENESISFD

iTrader: (13)

^ So basically this stuff is flammable if there is a leak? Seems like a bad idea to pump in propane into your refrigerant system and hope you dont crash or have an engine fire.

If there is an engine fire it can be hot enough to melt the aluminum piping of the AC system, will this cause an explosion? Seems like it would.

JM1FD

iTrader: (1)

It is indeed flammable! A guy nearly lost his Porsche 928 to this stuff when his fan blade cut through his low side hose and all the BBQ Gas leaked out.

Whitetiger777

iTrader: (1)

Question: do you personally know the guy whos Porsche caught on fire or is this a friend of a friend told me thing? I find there are a lot of rumors and false information of forums because people like to speak with authority on something they either hear or read from someone else without fact checking.

Here this is from the Enviro-Safe web site "Like most organic materials ENVIRO-SAFE is flammable, but its ignition temperature is 1585ºF at both 5 psi and 0 psi (which is better than the DuPont R-134a's ignition temperature of 368ºF at 5 psi and 1411ºF at 0 psi)"

So I doubt the refrigerant is to blame on the Porsche.

Also for those who asked, I used my AC today here in SoCal and it was so cold I had to turn it off at one point.

JM1FD

iTrader: (1)

Nope. But my BBQ Grill runs on propane, so I know it is delightfully flammable!

There's also this . Skip to about 4 minutes in to see the explosion.

Did you even click the link? There are tons of photographs documenting the hole in the A/C line and the damage done by the fire. What else would you suggest caused the explosion and fire?

Don't take my word for it. Just look at how ZERO automotive OEMs have ever put a hydrocarbon refrigerant into a production automobile. All the engineers they have on staff must be dumb, right?

j9fd3s

iTrader: (3)

well the good news is that Mazda switched from R12 to R134 for the 1994 model year (or was it 1995?), and didn't change much at all, so we know exactly what R134 does in an FD.

R12 is what it was designed for, and R134 is like having a big dog breathe on you...

other cars are different, the FC actually gets mixed results, i guess the pressures are higher with R134, so some cars are ok, but we had a local car pop an AC line

jm2fd

For North America, it appears that they switched over in 1995. The only major engineering change that I'm aware of is that they increased the fin density of the condenser for R-134a.