Speedtoys

No issues on anything on the car too tight so far.

But, I got the front 2 hoses cracked, but cant crack the rear ones without tightening the front ones, and it al wants to bend/torque.

Whats the trick here?

dr bob

lefty-loosey?

Speedtoys

Yes, but since this hangs in free air, im gonna bend the rear connections now

I guess I need to half-reinstall the fronts, and work it that way

Speedtoys

A 27mm wrench over the side of the valve body, and that did it.

All apart now..

The O rings in the fuel cooler...must be way in there, cant see them.

Mrmerlin

life is a lot easier if you have the hood removed for these repairs

Speedtoys

If you had to fight it, agreed.

Mine came out without any mechanical drama for the most part, the hood wasnt that big a deal.

Of course, taking two spare wrenches, and bending them with heat in a vise to make em 2" shorter DID help..but _way_ less hassle than removing the hood.

The rear ones were easily reached in the gap with the hood open.

bureau13

Apparently those fuel cooler o-rings can get pinched pretty easily. One of those is my big self-caused leak...

Speedtoys

If I have the same issue, the fuel cooler will come out, by removing the fuel lines...we'll have to see. I hope to pull vacuum by noon tomorrow.

The..source of the drier from 928intl, had the down-tube to the condenser a little off kilter. It wasn't perfectly straight, I'm guessing it was both slightly bent as a tube itself, and when the assy was welded to it, twisted just a hair.

I got it on and, and it fit straight and cleanly, by turning around the L bracket that screws to the condenser..that the drier then bolts to, to allow it to shift over about 1/2" or so.

And I had to use an O ring from my 'generic' stash, for Oring #28 in the drawings, for the back of the expansion valve..all I had on hand that were labeled Porsche parts, were multiple sets of the S4 Orings.

I might be back in there..but it'll be a lot easier and quicker next time, if I need to be.

dr bob

Jeff, if there's any comfort to be had, I spent the best part of a day fiddle-farting with the full o-ring and hose replacement, heat exchanger flushing, plus the compressor flush and fill. I still missed the o-rings under the compressor manifold plates, so was back in there a day later with the compressor out on the bench. Lots of work, but the AC has been awesome since the conversion. <20ºF Center vent temps at cruise speed on a 90º+ day, fan speed 2, black car in SoCal. Freezes fingers on the wheel. I reconnected the freeze switch finally so it would cycle, now that we aren't in the short-trip L.A basin any more.

Speedtoys

I just "finished" the job, and holds no more vacuum (none) than before i started.

I need to get a leak detector, some nitrogen, and sniff out the leak under pressure and re-assess.

Speedtoys

Plan tomorrow, hit it with compressed air, and soapy water bottle at the fittings...

*le sigh*

dr bob

If you decide to use compressed air, remove the drier and plug the connections or put the old drier back in. Unless you have a serious drier on the air compressor, it will add enough moisture to overwhelm/contaminate the dessicant in th AC drier.

bureau13

I'm in a similar situation. I replaced my butchered fuel cooler o-ring...now if I pull about 30 in-Hg vacuum and turn off the pump, after a couple hours it's down to 20 in-Hg. Much better...but clearly nowhere near good enough. I still haven't put on the new drier, but I really want it to be a closed system when I do. I don't suppose I'm lucky enough that my leak is at the old drier o-rings?? Lol probably not...

dr bob

bureau-Jeff:

At some point you'll decide that you can invest in or borrow/rent a small tank of dry nitrogen, a regulator and a couple fittings to let you connect it to the car. That way you can test the system under pressure, a much better 'test' than seeing how much leaks in when there's a maximum 15 PSI difference in the wrong direction. If you want to test the fuel cooler connections under vacuum though, you can try spraying the connections with water while vacuum is applied to see if it gets sucked in. Crude, plus you might get water in the system if it is in fact leaking.

To test for leaks in large industrial vacuum systems (like steam turbine condenser systems), we use helium and an electronic helium detector. Place the detector at the discharge of the vacuum pump, then go connection by connection, puffing helium around each one. When you get to one that's leaking, the detector goes off. This is anectdotal info, since operation under vacuum isn't what we seek in service. Still, if I had a handy helium leak detector, I'd be sorely tempted to try it after putting some helium (from the party supply store...) in the system under light pressure. Helium atoms are way smaller than refrigerant molecules, so you'd be finding and fixing some helium leaks that wouln't leak refrigerant. Turns out nitrogen is cheaper and the soapy-water tets on connections is usually adequate for our needs.

bureau13

Right...the vacuum test was me hoping it would hold steady after repairing the huge fuel cooler o-ring leak. Finding that equipment to borrow or a shop that can do the test is next on my list.