Heikki Lindholm

Q: Working on the G5 quad liquid cooling system

I have a G5 quad with the one pump Delphi LCS ("version 1"). I'm guessing the LCS is clogged because when the machine sits idle (even in reduced CPU setting, which cuts the GHz in half), the fans and the pump slowly, over several hours, go to full speed. Temperatures of CPU B, particularly the second core, shoot to near 100C when loading the CPUs. ASD 2.6.3 usually passes, but sometimes ends in checkstop and overtemp. A local mac service center, which I had the machine checked at (in hopes of getting free repairs because of a leak), said it's fine.

 

As a simple first measure, I tried replacing the thermal paste on the CPUs, with little effect. The LCS didn't seem to be leaking or corroded anywhere, but when handling it, it sometimes made a bubbling noise, so, there's probably air in there. I thought I'd take the LCS apart next, but before that I have some questions which I hope someone can answer.

 

Which one, the upper or lower, is CPU A and which is B? I've read the machine runs on one CPU just fine, but which one?

 

If I switch the CPUs the other way around and later switch back, does something in the nvram reset so that thermal calibration needs to be run? I'd rather not run it as it seems to have mixed success.

 

What material/size are the CPU block O-rings on this system?

 

If I use a vacuum pump on the service valve (I gather it's of the "r134a high" type(?)), what would be a safe level of vacuum? Has anyone tried using the manual brake kits, or car cooling system refill kits that use compressed air and venturi valves, on the LCS?

 

I suppose I'm just going to try attaching a hose as a reservoir to the service valve and fill through that first, but if that doesn't bring satisfactory results, I'll level-up to some sort of vacuum method.

PowerMac

Posted on Sep 17, 2011 11:59 PM

Close

Q: Working on the G5 quad liquid cooling system

  • All replies
  • Helpful answers

first Previous Page 11 of 17 last Next
  • by Ramón G Castañeda,

    Ramón G Castañeda Ramón G Castañeda May 15, 2013 9:03 PM in response to romko23
    Level 4 (1,468 points)
    Desktops
    May 15, 2013 9:03 PM in response to romko23

    Yes, we don't have a definitive answer on that, but my G5 Quad has a single pump [as reported by Hardware Monitor] and, according to its serial number, it was manufactured in late June of 2006.

  • by G5Lover,

    G5Lover G5Lover May 15, 2013 9:26 PM in response to romko23
    Level 1 (0 points)
    May 15, 2013 9:26 PM in response to romko23

    That IS very interesting indeed! I've also heard of the techs telling customeres ther's nothing wrong with their G5 when the fans run full blast and their machine is overheating.

     

    From what I know, the later G5's had the duel pumps and Apple considered them far more reliable than the earlier single pump versions. This turned out to be true. Try finding a leaking G5 duel pump LCS story on the web. The duel pumps didn't appear to have leak problems. Stories of leaking single pumps are all over the web.

     

    The OP to this thread had a single pump version. That's not to say that the duel pumps don't have overheating problems when the coolant evaporates after several years. Neither duel or single pump systems are immune to evaporation over time. I will be flushing my duel pump for that very reason. (Evaporation and routine maintenance of the coolant).

  • by G5Lover,

    G5Lover G5Lover May 20, 2013 11:05 PM in response to G5Lover
    Level 1 (0 points)
    May 20, 2013 11:05 PM in response to G5Lover

    I finished my flush and fill of my duel pump Cooligy LCS yesterday and I'm happy to report the machine is up and running very quiet today. Everything went extremely well. Fan speeds back to normal and the machine is very quiet. Here's my celcius temps and fan speeds today.


    iStat05-20-13idle.png


    I was able to do a minimalist flush and fill only on the B Core side, of the LCS, replacing only one original hose from that side of the system, then converting one of the stub-offs on the radiator, to a reusable fill/flush valve like Chris did on his duel pump. I used Tygon plasticizer free hose for the replacement. Before I started the project, iStat Pro, reported no problems with the the A core temps so I did not flush that side or mess with anything related to it. I'm a firm believer in the saying, "If it ain't broke, don't fix it." I'm sure I will need to flush that side at some point but until it starts showing abnormal temps, and fans start to ramp up, I won't mess with it.


    The most important thing I discovered in this quest:

    Apple went to a lot of trouble to make this duel pump system leak free and vapor leak free. Upon close examination of the hose I removed, I found that it's lined with a clear polypropylene or polyethylene liner. It's not just black radiator or fuel line hose, it's made from two separate materials bonded together. I'll post a close-ups here soon.


    Also, the connections at the barbs have some sort of clear rubber sleeves just in front and behind the barb itself. These sleeves are put on before the hoses were installed-probably to create a tighter friction fit against the inner liner of the hose. Also as shown in earlier pictures on this thread by Chris, Apple epoxyed the ends of the hoses to the pipes just to be sure.  I'm sure that the original hoses would never need service if left alone. IMO, on this duel pump system it's best to remove as few hoses as possible when servicing it. In addition, because of the propylene liner on the inside of the hose, there was no crud build up like we've seen in some of the pictures of earlier LCSs. Having this plastic liner also helps prevent water or gas vapor from escaping over time through the hose itself. Again, because of the nature of the original hoses, it's best not to replace them unless its absolutely needed. Of course unfortunately, they cannot be reused either. My product of choice to replace the hose is transparent plasticizer free Tygon hose.


    G5Lover

  • by Ramón G Castañeda,

    Ramón G Castañeda Ramón G Castañeda May 21, 2013 12:02 AM in response to G5Lover
    Level 4 (1,468 points)
    Desktops
    May 21, 2013 12:02 AM in response to G5Lover

    Thank you for the extensive report, G5Lover.

     

    Maybe I missed it in your posts, but I don't remember whether your machine is a G5 Quad, but I assume it is because you appended your posts to this G5 Quad thread.

     

    It appears that the vast majority of leaking LCS G5s were dual-core machines, not quads.

     

    There's a lingering suspicion on my part that there isn't a definitive source out there detailing the true history of the LCS systems used by Apple on G5s.  Most controversies seem to concentrate on arguing the single versus dual (not "duel", please!  Duels were outlawed in the past millennium in the civilized world ) pump systems, as if there had been only two kinds, which is inaccurate.

     

    Apple used Delphi, Cooligy and Panasonic brand pumps on various models.  The Panasonic ones were reputedly rejected as proven poor performers and not used again.  The latter  were only used in non-Quad models according to some sources.  Some of the G5 Quad sport combined both Delphi and Cooligy components.  Al of these various facts have been rehashed more than once in the various threads to which links are provided in various posts of this thread.

     

    As far as the G5 Quad, through the serial numbers on at least a dozen machines (including my very own G5 Quad) made at Apple's Elk Grove (Sacramento, CA) factory, less than 20 miles from my home, during the last seven weeks of the G5 Quad production run before Apple switched to Intel, and they all have single-pump systems.  If there was indeed a change for quality reasons, it would have been to abandon the dual pumps in favor of the single-pump system.

     

    I do from time to time run into techs in my area that used to work in that particular Apple factory.  I hope to one day find a credible source. 

     

    Hope you enjoy your G5 Quad in any event, at that those dual pumps of yours don't suddenly and unexpectedly start dueling and killing each other.  

  • by BMaverick,

    BMaverick BMaverick May 21, 2013 7:22 AM in response to Ramón G Castañeda
    Level 1 (10 points)
    May 21, 2013 7:22 AM in response to Ramón G Castañeda

    If the pumps duel each other, I have a limited stash of G5 pumps still available.

     

    Both Sean and G5Lover took advantage of this. 

     


    Even though I have a stash, that stash is getting smaller as time goes forward.  These G5 LCS pumps work in both the Delphi and CoolIT units.  Also, I offer them to the Intel/AMD OCing WCing people after swaping the wires in the end connector to the ATX formfactor standard.  Thus, the replacement pumps will be gone before the end of the year.  Mine are new, never used, with the original Laing 50,000+ run life fully intact.  Do a google search on "bmaverick".  

     

     

     

    Hope this info helps,

    BMaverick

  • by Ramón G Castañeda,

    Ramón G Castañeda Ramón G Castañeda May 21, 2013 7:57 AM in response to BMaverick
    Level 4 (1,468 points)
    Desktops
    May 21, 2013 7:57 AM in response to BMaverick

    BMaverick wrote:

     

    If the pumps duel each other, I have a limited stash of G5 pumps still available.

     

    LOL ! 

     

    Seriously, as soon as I find a local (but not crooked*) tech willing to do it for me, I'll buy one from you just in case I have a future need to replace mine.  Off to google your web site. 

     

    (* The one tech that did a fantastic job for me back in 2011 also misused the credit card info I submitted to him to pay for the repair job—not involving the LCS—to attempt to charge very substantial personal orders for himself at walmart.com.  Fortunately the BofA caught the suspicious, unusual activity and cancelled my card before the charges went through.  As a result I got a free repair job on my G5 Quad, as I never heard from the guy again.  A police report was filed.)

  • by G5Lover,

    G5Lover G5Lover May 21, 2013 10:50 AM in response to Ramón G Castañeda
    Level 1 (0 points)
    May 21, 2013 10:50 AM in response to Ramón G Castañeda

    Ramóne,

     

    Yes, my G5 is a 2.5Ghz quad built in Oct. of '95 it has the Cooligy LCS system with duel Delphi pumps. The pumps are labeled Delphi. The plastic cover over the heat blocks is labeled Cooligy. From what I understand talking to BMaverick, the Cooligy system and pumps were designed in cooperation by Laing, Delphi, and Cooligy. So all three companies had a hand in creating this LCS.

     

    On your second point I believe you are correct, "The vast majority of leaking LCS G5s were dual-core machines, not quads." I believe that also would make them all single pump leakers.

     

    I purchased my machine used in 2011 from a reputable dealer. I don't know but it's possible that they refurbed the unit with a replacement LCS. That would explain the later Cooligy system. Another source of confusion between systems is that some people might own used systems that Apple replaced the LCS with a newer version replacement. The new owners may not be aware of this. It does sound like Apple went back and fourth between the duel pump and single pump.

     

    But like I said, could it be possible Apple service replaced leaking LCS systems with different ones. Probably whatever LCS they had in stock at the time. That might explain much of the confusion.

     

    PowerMac, Mac OS X (10.4.11), 2.5G5Quad,10.5GB, 6600 W/Fan Cooler 256MB, Tiger

  • by Ramón G Castañeda,

    Ramón G Castañeda Ramón G Castañeda May 21, 2013 11:02 AM in response to G5Lover
    Level 4 (1,468 points)
    Desktops
    May 21, 2013 11:02 AM in response to G5Lover

    G5Lover wrote:

     

    …my G5 is a 2.5Ghz quad built in Oct. of '95…

     

    That's an obvious typo, you must have meant to type '05. 

     

     

     

    G5Lover wrote:

     

    …like I said, could it be possible Apple service replaced leaking LCS systems with different ones. Probably whatever LCS they had in stock at the time. That might explain much of the confusion…

     

    Excellent point!

     

    Thanks for replying. 

  • by G5Lover,

    G5Lover G5Lover May 21, 2013 11:50 AM in response to Ramón G Castañeda
    Level 1 (0 points)
    May 21, 2013 11:50 AM in response to Ramón G Castañeda

     

    That's an obvious typo, you must have meant to type '05. 

     

     

     

    G5Lover wrote:

     

    …like I said, could it be possible Apple service replaced leaking LCS systems with different ones. Probably whatever LCS they had in stock at the time. That might explain much of the confusion…

     

    Excellent point!

     

    Thanks for replying. 

    Ahaaa YES!

     

    I did mean 2005! Thanks I'll edit that!

     

    BTW, IMO, I think you should order a couple pumps from BMav if your planning on hanging on to your machine. That's what I did even tho there was nothing wrong with my pumps. "Knock on wood."

  • by Ramón G Castañeda,

    Ramón G Castañeda Ramón G Castañeda May 21, 2013 11:56 AM in response to G5Lover
    Level 4 (1,468 points)
    Desktops
    May 21, 2013 11:56 AM in response to G5Lover

    G5Lover wrote:


    …BTW, IMO, I think you should order a couple pumps from BMav if your planning on hanging on to your machine. That's what I did even tho there was nothing wrong with my pumps. "Knock on wood."

     

    I would really like to do that, as soon as I find a reliable tech willing to do it for me without my having to ship the machine out of the state of California.   I do plan to hang on to the machine for the rest of my life, which for a septuagenarian old geezer like me is not unrealistic at all. 

  • by G5Lover,

    G5Lover G5Lover May 21, 2013 12:07 PM in response to Ramón G Castañeda
    Level 1 (0 points)
    May 21, 2013 12:07 PM in response to Ramón G Castañeda

    Ramón,

    So I probably missed this in the thread and I hope you don't mind me asking again, but what are the problems you are having with the LCS? And what exactly were the previous repairs you mentioned you had done?

  • by G5Lover,

    G5Lover G5Lover May 21, 2013 12:41 PM in response to G5Lover
    Level 1 (0 points)
    May 21, 2013 12:41 PM in response to G5Lover

    Here is the picture of the inside of the Cooligy LCS hose I promised. As you can see it is made up of two separate products bonded together. A typical rubber on the outside with a poly plastic inside liner of (I'm guessing), polypropylene or polyethylene.

    128.jpg

    This liner creates a super durable virtually gas impermiable barrier. The earlier single pump systems didn't appear to have this type of hose—at least none of the rebuilds I've seen posted have indicated that this special hose was used.

  • by Ramón G Castañeda,

    Ramón G Castañeda Ramón G Castañeda May 21, 2013 5:17 PM in response to G5Lover
    Level 4 (1,468 points)
    Desktops
    May 21, 2013 5:17 PM in response to G5Lover

    G5Lover wrote:

    …what are the problems you are having with the LCS? And what exactly were the previous repairs you mentioned you had done?

     

    It has been my good fortune not to have any problems whatsoever with my G5 Quad after the aforementioned initial repairs.

     

    The outer aluminum case was  damaged during transport by United Catapult Delivery, aka UPS.  The private party that I bought from had in good faith gone out of his way to contract with a professional packing and shipping company in Lake Charles, LA, to ensure proper shipping, but my feeling is that some low-level employee(s) actually dropped the machine onto a hard floor before packing it to turn it over to UPS and never 'fessed up to the owner of the firm, as there was negligible damage to a single corner of the outermost cardboard box.

     

    _IMG0631.jpg

    _IMG0632.jpg

    Fortunately, there was no damage done to any of the internal parts.

     

    I used the occasion of the case swap to

    • upgrade the RAM to 16 GB;
    • install a mutant, flashed 550MHz nVidia GeForce 7800GTX 1,700MHz with 512MB VRAM video card to drive two identical but differently branded dual high-end v22" CRT monitors;

    • install a brand new ATTO ExpressPCI UL5D LP SCSI card

    • install physically separate Mac OS X Tiger 10.4.11 and Leopard 10.5.8 internal boot drives;

     

    —I have the intrusive Spotblight, Dashboard and Time Machine permanently disabled; 

    —USB wireless 'n' available but connected to the Internet via wired Ethernet;

    —FW flatbed scanner;

    —2 SCSI scanners (one tabloid-size transparency scanner and a film scanner);

    —various internal & external HDs;

    —FW Epson 2200 and Ethernet Samsung ML-2850ND printers;

    —2 X Back-UPS RS 1500 XS units.

     

    I run Photoshop 11.0.2;

    Adobe Bridge 3.0.0464;

    Adobe Illustrator 12.0.1;

    VueScan 9.0.96 [last version for PPC];

    Adobe InDesign 4.0.5;

    OptiCal 3.7.7;

    SpectraView 1.1.00;

    Fontographer 4.7.3;

    Adobe Acrobat Professional 8.3.1;

    MS Office 2008 (MS Word, Entorage, Excel);

    Several browsers like TenFourFox 17.06, Opera 10.63, Safari 4.1.3, Camino 2.1.2, etc.;

    and a host of other applications and utilities like Quick Time Pro, iMovie, iDVD, DiskWarrior. etc.

     

    The first five on that list run practically 24/7, simultaneously and screaming fast.

     

    I share both monitors through their respective front panel input selectors, and the keyboard. mouse and ocassional tablet through a rugged USB switch router box, with my Snow Leopard OS 10.6.8 consisting of an Intel Mac Book maxed out at 4 GB of RAM exclusively in order to run Adobe Camera Raw 7.4 and 8.1RC hosted by Adobe Photoshop 13.0.4, the only software that I need to run in 64-bit OS 10.6.x.

     

    I couldn't be happier with this arrangement.

  • by G5Lover,

    G5Lover G5Lover May 21, 2013 5:52 PM in response to Ramón G Castañeda
    Level 1 (0 points)
    May 21, 2013 5:52 PM in response to Ramón G Castañeda

    I couldn't be happier with this arrangement.

    WOW, no wonder you took so long to answer my question!! That was more of an answer than I expected. Thanks for the info. You just gave me some ideas! You've got that machine dialed. Very nice indeed.

     

    They definately dropped your machine really hard. That's a shame. I would recommend next time you need ship it, purchasing the actual packaging for that machine from an Apple service facility. You can probably get one of the custom boxes from these guys http://www.powermax.com/ They use a special custom box with moulded styrofoam padding that fits it precisely. Dropping it from standing height when packaged in the special box, usually will not do any damage. Looks your shippers dropped your's before it even got to a box.

     

    I found Fedex to be far more reliable when it comes to caring for fragile packages.

     

    Have you ever considered doing the LCS rebuild thing yourself? There are so many good resource people out there that have done it and are willing to give advice. Me included.

     

    I'm very leary of sending my machine out to have anything done that I think I can do myself. My personal motto is "If I want it done right I must do it myself." However, that doesn't apply to things I honestly feel are way beyond my skill level.

  • by BMaverick,

    BMaverick BMaverick May 21, 2013 6:21 PM in response to G5Lover
    Level 1 (10 points)
    May 21, 2013 6:21 PM in response to G5Lover

    Hum, that hose looks much like that used in automotive AC lines, high pressure fuel lines and some brake lines.

     

    The good thing is, the hose is a better quality, thus no pump VC is required for the LCS.

first Previous Page 11 of 17 last Next