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 12 of 17 last Next
  • by BMaverick,

    BMaverick BMaverick May 21, 2013 6:30 PM in response to G5Lover
    Level 1 (10 points)
    May 21, 2013 6:30 PM in response to G5Lover

    quoted ... 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. ... quote

     

    Actually, Delphi hired Laing to use an existing design pump D4 type and package into a 1U server compact size.  The result is the DDC (aka Delphi DC) pump.  Cooligy tried a few other pump makers out there, but couldn't improve the design and performance.  The Delphi pump DDC had the VC.  Apple asked Delphi to license the pump to Cooligy.  They did, but without the VC.  So, Cooligy had to resolve in using the special tubing and no pump VC.  In a way, that was a better design overall.  The rest is history. 

  • by Ramón G Castañeda,

    Ramón G Castañeda Ramón G Castañeda May 21, 2013 6:39 PM in response to G5Lover
    Level 4 (1,468 points)
    Desktops
    May 21, 2013 6:39 PM in response to G5Lover

    G5Lover wrote:

     

    …no wonder you took so long to answer my question!…

     

    Nah, I happen to be fighting acute pneumonia and bacterial bronchitis at this time, something not easy for an old septuagenarian geezer like myself with a host of other irreversible, chronic medical conditions.  So I find myself typing even slower than usual. 

    G5Lover wrote:

    They definately dropped your machine really hard. That's a shame…


    Looks your shippers dropped your's before it even got to a box.

     

    Yes; no doubt about that.

     

    The seller had requested and paid for both FedEx and an original G5 shipping box from Apple. The shipping company's employees obviously disregarded both requests.

     

    They used two new, but generic cardboard shipping boxes, one smaller than the other to fill the space between them with Styrofoam blocks and peanuts.  There was practically no appreciable damage to the smaller inner box, and only one bent corner in the larger outer box.

    These picts show only the inner box after removal of the Styrofoam cushioning blocks and peanuts:

    _IMG0619.jpg

     

    _IMG0626.jpg

     

     

    They were understandably very quick to refund the packing and shipping charges and to arrange for payment of the meager "standard" insurance coverage but refused to acknowledge the obvious and kept trying to shift the blame to UPS, who apparently didn't want to bother fighting the issue.

  • by BMaverick,

    BMaverick BMaverick May 21, 2013 6:44 PM in response to Ramón G Castañeda
    Level 1 (10 points)
    May 21, 2013 6:44 PM in response to Ramón G Castañeda

    As for finding a tech to refill the system, that is a hard question.

     

    I only know of four people personally who can do this without specialized equipment.

     

    Also, reading G5Lover's ability to change out the fitting to somehting that is more common to connect to is a big help.  If he creates a blog or something here with steps and pixs, that would be grand and helpful for all.

     

    The only way I have done an LCS is with a brake bleeder kit.  Yes, changing out the AC fitting to a brake fitting works.  Summit Racing has some that work if I recall.  This way, the brake kit can vacuum (evacuate) the LCS, and then refill via a reservoir tank.  Just using 33% Sierra PG coolant with 66% distilled water works, or buy it pre-made from Koolance, the LIQ-702 coolant.  http://koolance.com/files/products/manuals/msds_koolance_liq-702.pdf

     

    http://shop.advanceautoparts.com/webapp/wcs/stores/servlet/product_vacuum-pump-b rake-bleeder-kit-sunpro_9020007-p

  • by BMaverick,

    BMaverick BMaverick May 21, 2013 6:55 PM in response to BMaverick
    Level 1 (10 points)
    May 21, 2013 6:55 PM in response to BMaverick

    Also, if anyone needs a pump, PLEASE specify G5 pump when making an inquiry.  Else, you may get the reworked pump for Intel/AMD WCing extreme hobbists.   

     

    My stash is limited.  Once they are gone, there is no more.  I'm not a vendor, nor have any distributor supply to tap into. My pumps are G5 programmed with the 4th PWM wire.  The Swiftech, Corsair, and Koolane pumps are without the G5 IC logic chip and no 4th wire for the PWM. In the past 4-years, the supply has dropped to a mere 16% remaining.

  • by G5Lover,

    G5Lover G5Lover May 21, 2013 6:53 PM in response to BMaverick
    Level 1 (0 points)
    May 21, 2013 6:53 PM in response to BMaverick

    Actually, Delphi hired Laing to use an existing design pump D4 type and package into a 1U server compact size.  The result is the DDC (aka Delphi DC) pump.  Cooligy tried a few other pump makers out there, but couldn't improve the design and performance.  The Delphi pump DDC had the VC.  Apple asked Delphi to license the pump to Cooligy.  They did, but without the VC.  So, Cooligy had to resolve in using the special tubing and no pump VC.  In a way, that was a better design overall.  The rest is history.

     

    Thanks for clearing up those facts for us Mav.

  • by BMaverick,

    BMaverick BMaverick May 21, 2013 6:56 PM in response to G5Lover
    Level 1 (10 points)
    May 21, 2013 6:56 PM in response to G5Lover

    Glad to help where I have the supplier knowledge.  One thing I can't figure out is the quoting in this forum.

  • by G5Lover,

    G5Lover G5Lover May 21, 2013 7:09 PM in response to BMaverick
    Level 1 (0 points)
    May 21, 2013 7:09 PM in response to BMaverick

    BMaverick wrote:

     

    As for finding a tech to refill the system, that is a hard question.

     

    I only know of four people personally who can do this without specialized equipment.

     

    Also, reading G5Lover's ability to change out the fitting to somehting that is more common to connect to is a big help.  If he creates a blog or something here with steps and pixs, that would be grand and helpful for all.

     

    The only way I have done an LCS is with a brake bleeder kit.  Yes, changing out the AC fitting to a brake fitting works.  Summit Racing has some that work if I recall.  This way, the brake kit can vacuum (evacuate) the LCS, and then refill via a reservoir tank.  Just using 33% Sierra PG coolant with 66% distilled water works, or buy it pre-made from Koolance, the LIQ-702 coolant.  http://koolance.com/files/products/manuals/msds_koolance_liq-702.pdf

     

    http://shop.advanceautoparts.com/webapp/wcs/stores/servlet/product_vacuum-pump-b rake-bleeder-kit-sunpro_9020007-p

    I used a brake bleeder hand pump like the one you show but did not need to install a brake fitting in the radiator. I installed the same fuel shut-off valve that Chris used (see his pictures earlier in this thread). It worked very slick. I applied vacuum to the radiator with the brake bleeder thru the fuel valve when open. Then I shut it. Then I simply stuck the hose into the fluid and opened the fuel valve to suck the fluid into the radiator. I did this until the radiator was full and no more air could be sucked out with the brake bleeder. When I ran  the pump it confirmed that I was done. No noise or air bubbles at all. Worked like a charm.

     

    CLICK IMAGE TO ENLARGE

    FlushJob.jpg

  • by G5Lover,

    G5Lover G5Lover May 21, 2013 7:42 PM in response to G5Lover
    Level 1 (0 points)
    May 21, 2013 7:42 PM in response to G5Lover

    Here's a link to the shut off valve I used. http://tinyurl.com/kzskqpn

     

    But if I had to do it over I would now use this style. It would be easier to work with because of it's right angle configuration. http://tinyurl.com/ko995k9

  • by G5Lover,

    G5Lover G5Lover May 21, 2013 10:53 PM in response to G5Lover
    Level 1 (0 points)
    May 21, 2013 10:53 PM in response to G5Lover

    This info in this first paragraph has been mentioned before but it's worth mentioning again.The duel pump LCS radiator is divided into two separate chambers for coolant. An "A" Core side (for the "A" processors and "A" pump) and a "B" Core side for the "B" processors and "B" pump). One core for each pump. That being said, each core must be flushed separately. The radiator is really two separate radiators built into one.

     

    When I evacuated the old coolant out of one core only, I saved and measured the quantity. Each core holds apr. 125 ml of fluid.

     

    Diagnosis and compressed service log of my LCS flush: (G5 Quad with duel pump Cooligy LCS)

    Rule No.1 FIRST get iStat Pro widget to diagnose the problem.

    Rule No.2 If you have an overheating issue DO NOT DO A FAN CALIBRATION OR SYSTEM DIAGNOSTIC. IT ONLY CAUSES ADDITIONAL PROBLEMS!! THERE ARE WELL DOCUMENTED ERRORS IN THAT APPLE DIAGNOSTIC PROGRAM. Your problem is most likely one of these basic things- Plugged up radiator or filter, bad pump, super low on coolant.

     

    iStat Pro widget is a wonderful app. because it essentially tells you what's wrong. It gives you all the info you need to figure out what kind of heating issues you have and what your repair approach will be.

     

    iStat told me that my pumps were operating fine but the fans were running extra fast to compensate for lack of liquid cooling, and the "B" cores temps were always 30º warmer than the "A" cores. The "A" cores at idle always ran at normal temp in the 30ºC range. That told me that the "B" core side was the culprit of poor cooling. Since both "A" and "B" pumps were running at the same speed, I figured the "B" side radiator or filter was simply plugged up with electrolysis residue and/or radiator dye sediment. After cleaning the radiator, I found that to be exactly the case. I reverse flushed just the "B" core that was overheating with boiling tap water mixed with about 1/16 by volume Zerex Super Radiator Flush. (safe for aluminum radiators and multi-metals and plastics.) http://tinyurl.com/os2t3bv

     

    When I reverse flushed the "B" side, I got loads of tiny pepper sized grains of green copper oxidation along with the same size red crystals. The radiator fluid was red, so the red crystals were dye sediment from the radiator fluid. Reverse flushing is critical because it forces the sediment backwards in the system, releasing it from the coolant filter and radiator. I did the hot flush twice flushing in both directions. Then I let the hot mixture cool in the radiator. I then flushed cool distilled water in both directions through the LCS until the water came out clean. I drained the distilled water out hooked up my hoses and was ready to put new coolant in. I used Koolance 702 http://tinyurl.com/p253ow5 because it has the longest service cycle of any coolant-3 years service life. Plus, it's formulated to work safe with mixed metals and plastics in LCS environments. It's dye also does not turn to sediment like other lesser coolants.

     

    Once back together I started the machine guess what?… quiet as a mouse! iStat reported both "A" and "B" cores running in the same 30ºc range at idle. This was my first crack at flushing the LCS and it really wasn't that hard. I will say that I did my research and took my time collecting data before I turned one screw on my machine. Oh, I also dreamed about it a few times (gross understatement)

    All in all, I'm very happy I was able to do this flush by only replacing one original hose, with minimal tampering and invaision of other hoses.

     

    Here's my idle temps again.

    iStat05-20-13idle.png

    Hope this helps those wishing to take the leap and do the flush.

  • by G5Lover,

    G5Lover G5Lover May 21, 2013 10:45 PM in response to Ramón G Castañeda
    Level 1 (0 points)
    May 21, 2013 10:45 PM in response to Ramón G Castañeda

    Ramón G Castañeda wrote:

     

     

    The seller had requested and paid for both FedEx and an original G5 shipping box from Apple. The shipping company's employees obviously disregarded both requests.

     

    They used two new, but generic cardboard shipping boxes, one smaller than the other to fill the space between them with Styrofoam blocks and peanuts.  There was practically no appreciable damage to the smaller inner box, and only one bent corner in the larger outer box.

    These picts show only the inner box after removal of the Styrofoam cushioning blocks and peanuts

     

     

    They were understandably very quick to refund the packing and shipping charges and to arrange for payment of the meager "standard" insurance coverage but refused to acknowledge the obvious and kept trying to shift the blame to UPS, who apparently didn't want to bother fighting the issue.

     

    ********!

     

    G5Lover

  • by G5Lover,

    G5Lover G5Lover May 22, 2013 7:53 AM in response to G5Lover
    Level 1 (0 points)
    May 22, 2013 7:53 AM in response to G5Lover

    Also, this is a VERY IMPORTANT note and I forgot to add it to my log above— Make sure when adding permanant hose clamps, valves and the like to the LCS, they are positioned even with the top or below the top of the radiator. By "TOP I mean the side of the radiator facing you when it's installed in the machine. Otherwise the LCS cover, clear plastic shield, and side door covers will not go back on your Mac after the LCS is installed!! There is very little if any clearance between the LCS, it's cover and the inner plastic shield door!

  • by G5Lover,

    G5Lover G5Lover May 22, 2013 1:23 PM in response to G5Lover
    Level 1 (0 points)
    May 22, 2013 1:23 PM in response to G5Lover

    What I Flush With

     

    Thought I would show what I used to back-flush my LCS. I got lucky finding this tool in my father's garage just a couple months ago! My Dad is a retired M.D. and he used this medical irrigation syringe in his practice to flush wax out of patient's ears. He was about to throw it out.

    FlushingTool.jpg

    It's made from chrome plated stainless steel and will hold 3 oz of any kind of fluid. The plunger inside, seals against the sides with a large rubber "O" ring. It will work for sucking liquids and squirting liquid. Surgical tubing fits very snug on the needle and the needle is removable. When I first saw it I knew It could come in handy for something other than flushing wax from my ears, so I latched on to it and put it in my tool box. 

     

    Well that time came sooner than I expected! I used it to back-flush my LCS with the boiling hot water mixture of Zerex radiator flush. Just for giggles, I went online and tried to find one like it and can't come up with anything close. The nice thing about using this is there was no need to use the LCS pumps to do the job. It made flushing go really fast. There's got to be something similar out there in the mechanical tool realm that will essentially do the same thing. Having to use the LCS pump to do it is time consuming.

  • by G5Lover,

    G5Lover G5Lover May 22, 2013 8:14 PM in response to G5Lover
    Level 1 (0 points)
    May 22, 2013 8:14 PM in response to G5Lover

    Thought I'd share this method I came up with of safely running the pumps without accidentally touching the other electrical pins on the pump plug. Click the photo to enlarge it to read.

    PoweringThePumps.jpg

  • by G5Lover,

    G5Lover G5Lover May 28, 2013 10:47 PM in response to G5Lover
    Level 1 (0 points)
    May 28, 2013 10:47 PM in response to G5Lover

    Here's a shot of a cross section of hose and the rubber sleeve that Apple put underneath the hose connections, (probably only on the duel pump models) just in front and behind the barbs of the aluminum and plastic pipes. This clear rubber sleeve helped make a better seal against the inner walls of the hose.

    RubberSleeve copy.jpg

    Note the right end of the rubber sleeve. One corner of the sleeve had been accidentally pinched under the hose from the factory build.

  • by G5Lover,

    G5Lover G5Lover May 31, 2013 5:47 PM in response to Heikki Lindholm
    Level 1 (0 points)
    May 31, 2013 5:47 PM in response to Heikki Lindholm

    Interesting, that there are some 1-3/4 inch diameter black rubber bands (each green square in the photo is 1/2") that Apple wrapped around the lower cooling lines and up over the processor screw retaining plates. These rubber bands on my machine had deteriorated and were broken and just hanging when I removed each processor. They were originally used to temporarily hold the screw retaining plates in position as the processors were being installed.

    BlackRubberBand.jpg

     

     

    As you can see by the photo below, I replaced them with new rubber bands before re-installing the processors. It's not necessary to do this, but it does help position the screw plates when re-attaching the processors. There is one rubber band/per processor plate. It hooks over one ear of the plate wraps underneath the cooling line, then up over the other ear of the plate.

    ProcessorPlates.jpg

first Previous Page 12 of 17 last Next