A/C change on the beater - amazing difference!

Not entirely OT, trust me.

I've done quite a bit of work on The Beater during the last few weeks, most notably installing a 4.5 inch bolt and bracket that was supposed to secure the engine cradle to the chassis. Prior to the repair, the left-rear of the engine cradle sagged a few inches down and slopped around quite a bit. This not only created noise, but horrendous handling on the highway. And of course, after bolting this thing back up properly, it had to be re-aligned. One of the rear shocks was also frozen in place, and I had to change both out. Much better handling now, oh yeah.

Even more interesting was the R-134a changeover. I changed out the accumulator/dryer unit, popped the old orifice tube out and used this fitting to blow out all of the old oil with some compressed air, (surprise: no oil came out - the system was completely dry!), installed a new VOV, installed 12 oz. of PAO oil (ester, not PAG) and about 18 oz. of refrigerant, just enough to get the high-side pressure up to about 325 psi.

What a difference! On a 100 degree day, the air comming out of the vents will nearly cause frostbite. In less than one minute, the ambient temp drops to the mid-70's, and will dip into the 50's in just a few more. Astounding performance. I would have never believed that the system in this stupid old beater car could ever work so well.

I did not evac the air/moisture out of the system prior to filling. Normally this is not a good thing. I gambled that the desiccant in the new dryer would take care of the moisture, and that the extra air in the system would not dilute the refrigerant enough to make a significant difference. I ended up being right on both issues. With a little luck, the seals, hoses and compressor won't die because of the high pressures and corrosive nature of the new refrigerant. So far, so good.

A note that specifically pertains to Mustang owners:

One reason that the changeover worked so well is because of the VOV I installed. It looks similar to a normal orifice tube, however the internals meter the refrigerant more efficiently, resulting in much cooler temps at idle and less compressor flooding. In fact, the compressor works less at idle than at highway speed, yet maintains excellent cooling performance.

Anyone who has the A/C repaired/maintained on their Mustang should have one of these installed. They work incredibly well, and will boost the performance of any automotive R-134a system out today.

The cost for this little gem: $4.95. They can be bought online, or as I did at Kragen. The counter help was completely ignorant, and I had to insist they give me a specific part number I obtained online; none knew anything about VOV's, so be prepared for this if you obtain one this way.

-JD

_________________________________ JD's Locally-Famous Mustang Page: http://207.13.104.8/users/jdadams

Reply to
JD Adams
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Look out Charlene!

This is where you lost me. What exactly *IS* the VOV. Reason I ask is that while nothing is actually *wrong* with my Mustang's A/C, I've never been happy with it. It gives out tepid air at best, never that frigid air that I need to back off. The A/C actually failed on me during the hottest drive of the year to Las Vegas in the middle of August. Underhood temps were so high (my gauge even started to climb) during an uphill traffic jam past Baker that my A/C stopped blowing cold air--for no reason. We stopped at state line and had a cold one. An hour later, I started my car up, and the A/C was fine! Wierd. Even though it's working, it's never been great.

Later Vic

Reply to
Victor DiMichina

A VOV is the same thing as an orifice tube that now exists in your A/C system, except these better meter the flow of refrigerant, making life easier for the compressor, and making the A/C system far more efficient in every aspect.

It works much like an expansion valve in older systems. They directly replace th existing orifice tube, and they're not expensive. Most new cars now come with one of these, and I highly recommend installing one if your A/C is ever being worked on.

Your A/C system sounds like it's undercharged. Most Mustangs are sold that way, right off the dealership lot. Mine turns the cockpit into a freezer if I leave it on more than a few mins., however, I check/charge mine 2X a year for peak performance. I haven't yet installed a VOV yet; I should have time to noodle with it later this year.

-JD

_________________________________ JD's Locally-Famous Mustang Page: http://207.13.104.8/users/jdadams

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JD Adams

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Mick

Reply to
Victor DiMichina

Same here. The A/C performance increase will flat-out amaze you, and I have yet to meet any mechanic who doesn't think they're long overdue.

-JD

_________________________________ JD's Locally-Famous Mustang Page: http://207.13.104.8/users/jdadams

Reply to
JD Adams

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