automotive A/C gauges

[masraum]

I need to do some work on the AC in my miata, so I'll need a set of gauges.

I see that harbor freight has a set for $35, the local parts store has some for $80, and Sears has a set for $120.

I suspect that any of them would work OK, and the harbor freight stuff probably isn't much different than the $80 stuff at the parts store, but I figure I should check with you guys. I'd hate for something to explode on me.

Any thoughts.

Pretty sure it's already R-134a, so I should be able to work on it and source the chems.

Also, I've never done any AC work before. I figure I need to charge it up with some leak detect dye, fix the leak, and then recharge. I understand that it's a pressure differential that I'm looking for, but that's the extent of my knowledge. Does anyone know of anyplace online that's got a decent write up on what I need to do/know?

[masraum]

I found this link for recharging. Looks decent.

http://www.aa1car.com/library/ac_recharging.htm

[Scott R]

You will probably save yourself some money by taking it to a shop. After the AC manifold set you will need a leak detector, then a vacuum pump/recovery system to finish the job. I let people in Denver use my manifolds and recovery machine due to the cost of this equipment.

[Tim Hancock]

Steve, I think the cheap gage/manifold set will work fine (I use an ancient set with no issue), but the vacuum pump is going to be the tough thing to latch onto (I had a someone give me an electric one).

Some claim the little air operated venturi pumps will work, but they just do not pull a very hard vacuum. The idea behind evacuation, is to "boil" out any moisture that has entered the system due to exposure to air w(water boiling temp decreases as pressure decreases) . It takes a good vacuum pump and time to "boil" off the last little bit of moisture from a system. I am not the type to preach against DIY jobs and some folks have obviously got by with less than proper evacuation, but my "guess" is that it "could" lead to compressor failure or less efficient operation.

[Porsche_monkey]

I just had my system evacuated, a sealer added, and a full recharge for under $200. I think that's cheap enough that I wouldn't do it myself.

And the next day it was about 100 degrees. I still be sweating it out if I tried to do it myself.

[masraum]

Thanks all, I'll check around for a good place that does AC work. Two things that I've always farmed out in the past, automatic transmission rebuilding and AC work. I guess I'll keep doing that.

[NICKG]

i just did my ac...cost me 13 in r134...i have the stuff and i do all my neighbors and charge 50 to do it. needless to say it is a nice investment.

[turbo6bar]

It's not particularly difficult work, but I would not bother unless you're interested or need to work on multiple cars.

[Tim Hancock]

Since I got the equipment (for free!), I have topped off my 134 converted BMW once. I found the leaks in my '79 SC then got it going again on 134 (inital charge lasted two years, just topped it off with 1 can last week after those initial two years). I also rebuilt/sealed my daughter's 924S previously dead AC and charged with 134 last year and just topped it with 1/2 can last week. Having as many old cars with AC as I do, it has been incredible to be able to fix these things for basically just the cost of a couple cans of 134.

Now if I can just pick up a used tire mounter and balancer, I will be free from the numbnut kids who typically are employed by most of the tire shops these days! There are still SOME shops around with knowledgable employees, but when I know more about how to do the job than the average "professional" working in these places....well I would rather just do it myself.

If you want something done right.....

[turbo6bar]

I concur. Being able to work on A/C systems is great. It's doubly good when you can service home A/C units.

Hancock, check eBay for tire equipment. I spied a local tire balancer for $250 and snatched it up. For the hub centric wheels on your BMW and Porsche, it's absolutely marvelous. Now, I just need a tire mounting machine to round out my collection. I must have a disease.

My motto, "Why pay someone to fuch it up, when I can fuch it up perfectly fine for free!"

[on2wheels52]

We used to call the little refill sets 'suicide kits', postumously named after some schmo hitching one up to the high side.
Jim

[Tim Hancock]

Originally posted by turbo6bar
I concur. Being able to work on A/C systems is great. It's doubly good when you can service home A/C units.

Hancock, check eBay for tire equipment. I spied a local tire balancer for $250 and snatched it up. For the hub centric wheels on your BMW and Porsche, it's absolutely marvelous. Now, I just need a tire mounting machine to round out my collection. I must have a disease.

My motto, "Why pay someone to fuch it up, when I can fuch it up perfectly fine for free!"

Yeah, I have gotten to the point that I order my tires from Tire Rack then haul the loose wheels to a local tire place and get them mounted and balanced. Usually costs $20-$30 per wheel. Other than my Toyota truck, I dont trust those dipshiits to touch my cars. They have scraped my front valences, jacked in the wrong place damaging the under body, used an impact wrench on aluminum lugs, put clamp on weights when I specifically asked for stick ons etc etc. Most places have policies that don't let you back in the shop to babysit and if you tell them to be careful with your "Porsche" wheels, they think you are being a snob. I have complained to managers and the shiit just kept happening.

Sure I could probably go to a shop that charges triple, but I have too many cars to pay thru the nose for what should be simple tasks. Todays kids in general just are not as good at mechanical things as they used to be. Too many computer games and not enough wrenching on minibikes, go-carts and cars out in the garage growing up.

I never thought to look on E-bay for tire equipment, I will have to do that every now and then.