MA-70 A/C gas conversion

**HKS_TRD** · 21-12-2008, 07:03 PM

I'm wondering 2 things

1, how I can tell if my MA-70 has been converted to the newer type of gas
2. what is involved in converting to the newer style gas

My A/C is in bits at the moment while my engine bay is being painted so now is the time to put it back together in such a way that it can use the new gas

Cheers
Dan

**CrUZida** · 21-12-2008, 07:56 PM

There is an AC thread going on at the moment.
Not all places convert to R134A, some use HR12 without needed to change anything.

All that gets changed when R134A goes in are the fittings on the high and low pressure side. There is one near the firewall, and one infront of the radiator. If they are small with little black plastic caps its probably the old gas, if they are large with one red and one blue then its on the new gas. I doubt it will be any cheaper to do any work yourself. Just reinstall the current system and the aircon place will do the work needed.

**HKS_TRD** · 21-12-2008, 08:00 PM

I'm going to reassemble it, but if there were any parts that needed substituting, doint it while the motor is out is easier, rather than have someone put scratches etc as well as it being harder when its all back together. Going by memory here, at the firewall there was just the two metal nuts to undo the fittings. Along the chassis rail there was a red metal cap on what looked sort of like a tyre valve. Cant recall what was at the front of the car right now but I dont remember a blue fitting.

The system had no gas when it was taken apart so I need to suss out where the leaks were anyway.

I thought it was mandatory to switch to the new gas?

**CrUZida** · 21-12-2008, 08:12 PM

They can't reuse R12 but HR12 is legal to use and is a drop in replacement.

The only thing they will change that takes some effort is the dryer, which is infront of the radiator.

Just tell the radiator shop you've had the whole system apart and they'll make sure they check for leaks. Also when you put it back together make sure all the seals are in good condition, and are a bit lubed.

**HKS_TRD** · 21-12-2008, 08:16 PM

Cheers for the info, was doing a quick search but could not find the thread could you give me a link?

I was planning on using all new O-rings as there is not that many of them, and getting the condenser pressure tested. It all used to work really well till it lost the gas so I hope the compressor is still OK.

When the car is all together the dryer is a bit hard to get to. Do they keep my lines and just replace the dryer? One of the lines going to it is pretty long and the shape would need to be just right.

I guess I need to find an A/C shop here and talk to them, though I have a feeling someone on here with an MA-70 must have been through it all

**wa5** · 21-12-2008, 08:20 PM

on the same page as this thread....

http://www.toymods.net/forums/showthread.php?t=17373

**HKS_TRD** · 21-12-2008, 09:02 PM

Cheers just checked it out now

**CrUZida** · 21-12-2008, 11:46 PM

They just replace the dryer.

I had mine converted to R134a 4 days ago.

**The Witzl** · 22-12-2008, 09:15 AM

Peewee speaks teh truth.
I just installed an R12 aircon system in my AE82 corolla last weekend..... i just installed everything i had, made sure every fitting and connection had a good o-ring seal, and took it to my local a/c shop.

Told them the story, asked them to test the system for leaks first (they found one, and replaced the seal).... and then he converted the system to R134a and added gas (converting is just replacing the drier and the fittings as peewee said).

Only cost me $220.