LCS repair info for Powermac G5 dual 2.5

[photonorm]

Hey Josh,
Thanks for the post. Since the machine booted up normally (I posted an update after you) I suspect it has to do with a heat issue and not a hardware failure somewhere else in the machine.

Question is why does it run so hot?

 

[Joshuarocks]

Hey Josh,
Thanks for the post. Since the machine booted up normally (I posted an update after you) I suspect it has to do with a heat issue and not a hardware failure somewhere else in the machine.

Question is why does it run so hot?

Hmm.. what G5 is it?? Sounds like the LCS might be failing, or beginning to fail. Leaks were more severe on the Dual 2.5 2004 G5 and the Dual 2.7 Early 2005 G5's.. Quad's have better and more reliable heat pumps.

 

[photonorm]

That is certainly a possibility but I see leaks and I check on the pump to make sure it is working. I have Temperature Monitor running and I have it set to give me temp warnings. I also have Activity monitor running so I can see what the processors are doing and if I am really working the processors I listen for the fans to spin up and the the temp to go up as well.

I am keeping a log of my temps to make sure they stay consistent. I have a feeling that it might be my application of thermal paste or maybe the processor cards are not as close to the heat block as they should be. It is only one processor that hits over 200-220ºF on heavy loads. The other processor is a good 20-30ºF cooler.

Thanks for the suggestions and posts. If you have any other suggests please keep them coming.

Norm

 

[vohdoun]

Something is still wrong with the setup then if one processor is 20 - 30 degrees cooler. Between my two you're only talking a minimal of 1 - 2 degrees difference, high or low, idle or load and most times they are usually in sync.

 

[Joshuarocks]

That is certainly a possibility but I see leaks and I check on the pump to make sure it is working. I have Temperature Monitor running and I have it set to give me temp warnings. I also have Activity monitor running so I can see what the processors are doing and if I am really working the processors I listen for the fans to spin up and the the temp to go up as well.

I am keeping a log of my temps to make sure they stay consistent. I have a feeling that it might be my application of thermal paste or maybe the processor cards are not as close to the heat block as they should be. It is only one processor that hits over 200-220ºF on heavy loads. The other processor is a good 20-30ºF cooler.

Thanks for the suggestions and posts. If you have any other suggests please keep them coming.

Norm

If you know for sure its the fact you didn't apply enough thermal paste, shut down the machine and re-apply thermal paste, making sure you cover the core completely. Check to problems with the processor card and it being close or not close enough to the heat block. At this point it doesn't sound like a LCS problem.

 

[photonorm]

I agree, Josh, that it doesn't seem to be a LCS problem.

As for processor card being not close enough to the heat block, I am not sure if that is something I can adjust.

Since I have a working machine I need to get a bunch of production off my plate then I will pull the LCS and check the processor card distance and thermal paste application.

I am using Temperature Monitor to keep a close eye on the temps and was reading the manual a.k.A Temperature Monitor Help (from the help menu) and it lists the max temp for my machine as 190ºF. Well, I have gone above that value on the hotter of the 2 processors. So this is a fix that will need to happen sooner rather than later.

I have attached a screen shot of what my temps were when I was exporting/processing files out of Lightroom. You can see the obvious difference between the 2 CPUs and how quickly the temps dropped when the machine returned back to idle. This really points me in the direction of one or a combination of the following:
1. Not enough Thermal Paste
2. Processor cards too far from the heat block
3. The heat block copper fins (the part that is on the inside of the LCS) are not sufficiently cleaned to allow for efficient heat transfer.
CLICK ON IMAGE TO SEE IT LARGER



I hope it is either 1. or 2. since those don't require me to disassemble the LCS again and refill.

I will update with more info as needed. Otherwise, I will give a detailed report after I check the thermal paste and processor card distances.

Thanks for posting

 

[Joshuarocks]

Just got a G5 Quad myself

Here are the specs for my machine coming to me:

250gb harddrive
500gb harddrive
6 x(1gb) ram
Nvidia GeForce 7800GT - I assume this is the much better video card for this system, I know its not the quadra, but is the 7800GT much better than say the 6600?

Here is what the person wrote who is selling it...

250gb harddrive
500gb harddrive
6 x(1gb) ram
Nvidia GeForce 7800GT

And all I paid for this system was 500.00 + free shipping!! Again, I have a 2010 Mac Pro.. but I don't think I will ever use it for anything requiring pro-apps and multi-threaded apps.

Hi Josh,

I have not had any problems with the cooling system. The computer works great. I actually like it better than the new mac pro i got to replace it. The only reason i am selling it, was cause i had to upgrade to stay current with my work computer.

I had to have it fixed one time, for a power supply thing inside. It was all covered under my apple care and the mac store did the work. That was a while ago and no problems since.

I have the original disc that came with it, but I have upgraded to 10.5.9 operating system. So you can use whats on it or turn it back to just like it came from apple.

I will be sending it in the box that my new mac pro came in since they are the exact same size. That will be the best way to ship it.

The person selling me this told me that he never had any problems with the machine other than the power supply replacement due to Apple having some power supply issues at the time w/ certain G5's. He also reported that the LCS is working great - assume its the much better Panasonic one and not the Delphi.. He told me the LCS did NOT have the two black boxes on it, so I assume it is the panasonic..

What do you think? When I get it.. should I take it to the Apple store and just have them inspect the LCS and also what preventative measures should I take to ever prevent a leak? Since he has had it this long and its mint like, I assume that a cooling leak might not happen at all?

Sorry, I changed the thread a little bit, just wanted you to know that I too have a Quad G5 on its way to me.

Josh.

 

[photonorm]

I would appreciate it if the thread continues to be about Dual 2.5 LCS troubleshooting and dialogue specific to readers looking for info about LCS repairs and troubleshooting.

Thanks

 

[reddrag0n]

Very nice writeup about the G5 LCS. I recently got my hands on a DP 2.5 G5 (not the Quad version) and i got the red LED's too on both processors. From what i can deduce, it's a thermal thing. I recently ripped apart the Delphi unit to find that i had a small amount of leakage on the waterblocks (not enough to damage the logicboard or the PSU) and a small amount of *white rice* on one of the cpu's. My radiator had a very large calcium blockage and wouldn't allow fluid to pass through, so after several hours of ripping apart the LCS, i was able to clean all of the small hoses, water blocks, the pump and the radiator.

As for rebuilding the LCS, i was going to use a few off the shelf items to get it up and running again. I was thinking the Viton O rings, some local water cooling hose and special order a bottle or two of Primochill Ice (link here).

As for the hose, what's the diameter that you used? Since i am confused about 3/8, 5/8, and 1/2 hoses.

And about how much fluid did you use to refill the LCS?

 

[photonorm]

I can send you o-rings!

Hey,
Thanks for the kind words about the write up. You are correct in thinking the red lights on the boards are temperature related.

Everything you described indicates a coolant leak. You were lucky like me that the coolant that escaped from the LCS didn't take any vital components.

I looked at the link for the coolant. I would recommend using a coolant that has a color to it so you can better see it if it leaks. Also, when I was replacing the tubing I used a clear tubing in one section so I could actually see the coolant moving in the system. It will be easier to see coolant with a color than the clear coolant you mentioned in your post.

Here is a quick lesson on hoses. They are measured in OD (outer diameter) and ID (inner diameter). Lesson over

So when you see hose sizes and there is only a single number mentioned it is the OD they are referring to. I would simply take a section of your old hose and go to your local auto parts store and get some radiator type tubing. That is what I did and the salesman took my old part and found the same size tubing (OD and ID). I got 24" and has some to spare even after I had to cut off some new tubing after attaching it to the metal tubes that hold the coolant. For me...one the tube went on it didn't come off easily so I just cut it off. I broke the plastic part that has 2 ports on it from pulling too hard trying to remove the tube.

I don't recall what the size was of the tubing I used. I just has the guy get me more of what I brought him. As for the clear tubing I went to my local hardware store and make sure what I got was rated to handle the temps. Anything over 200 degrees F will work just fine. There isn't enough pressure in the LCS to worry about the pressure rating on the tubing and you will only probably use less than 3-4 inches of it.

I used about 200 mL of coolant. I believe you can read earlier posts in this thread to get the link to where I purchased my coolant. In my design, with the valve installed on the LCS, I added coolant once after I had the machine running for a couple of days. That allowed the smaller bubbles to collect and made the second bleeding of the air easier and faster.

If you want me to give you a couple of o-rings click on my user name and navigate to where you can send me an email. I will email you my address so you can send me a self stamped address envelope. I will put a couple of o rings in there and drop it in the mail. I had to purchase 50 because that was the smallest quantity. I have plenty to spare.

Hope this helps. If you need more assistance I will be glad to help.

Norm

 

[reddrag0n]

Your welcome about the kind words. I took some pics of what i had on mine. I will post them later on my website for all to see.

As for the coolant, i am kind of torn since there are so many to choose. Some extremists would say distilled water with an additive (Hydrx from Swiftech), others have said a product called "Feser One", others say the "Primochill PC Ice".

The clear tubing i was looking at comes from a local computer shop and they charge by the foot, so 2 feet would be good for me.

As for the O rings, you have the Viton rings? Sweet!!!! Once i get things a little more organized around here, i will definitely send an envelope your way.

 

[Benqvist]

photonorm:
Thanks for this comprehensive thread!

I have a G5 DP 2.5 GHz as the main production machine in my recording studio. This machine recently failed to boot. As I suspected, there was a coolant leak. With my LCS out of the computer and separated from the CPUs, a salty residue can be seen around both heatsink / CPU contact surfaces, like most of the G5s with LCS problems. But this residue seemed to have been built up over a long time, and there was no moisture to be seen or felt in this area.

Instead, the major (and probably the most recent) coolant leak was from the pump itself. So my best bet would be the o-ring inside the pump.

All the hoses and tubing seem ok, there are no signs of leaks here.

I will try to carefully drain the LCS and take apart the various components.

Will get back here shortly, hopefully with some pics, too.

The recording studio is running fine (albeit a tiny bit slower) thanks to a friend's DP 1.8Ghz (aircooled) that we use as a backup machine, so there's really no rush with this repair.

Curious thing is, we really "depend" on a working G5 machine, because our recording / DSP interfaces can only use the "old" PCI-X standard expansion slots...

EDIT: Forgot to mention some details on the symptoms: The PSU seems OK, despite a small patch of rust caused by the leaking fluid. Machine turns on, but no chime is heard and no display signal is detected from the DVI port. Shortly after, the fans start revving up to "jumbojet" speed.

Thanks again for all the info!
/// Mikael, Sweden

 

[Staples01]

hey reddrag0n, do you still have any more viton o-rings, im having the exact problems and tore my g5 right down and had the same rice problems and the orings were bad but couldnt find any online with out buying in bulk.

 

[reddrag0n]

hey reddrag0n, do you still have any more viton o-rings, im having the exact problems and tore my g5 right down and had the same rice problems and the orings were bad but couldnt find any online with out buying in bulk.

I'm not the one with the O rings, the one you want to maybe talk to would be photonorm

 

[Benqvist]

"Reservoir" in theory + o-rings needed!

Hey there,
just a thought:
Would it be possible to include a small coolant reservoir, just like in cars w/ watercooled engines? With all PCI slots occupied, there would be no space for a reservoir on top of the LCS, but one possibility would be to attach it outside the case, on the back panel...

Could this be helpful in the bleeding process, with the reservoir constantly "supplying" the LCS with coolant (thus making it "auto-bleeding")?

Only problem would be that the tubing between the LCS and the reservoir has to be installed as vertically as possible to let some, if any, air bubbles out. The PCI slots seem to be in the way once again. Again, these are only my thoughts and ideas, I will soon get back into reality when it's time to refill...

Now, I'm trying to get hold of some o-rings.

@photonorm: Is the o-ring inside the pump the same diameter and spec as the 2 "main" cooling block o-rings?

All the best,
///Mikael

 

[skorpan]

I would appreciate it if the thread continues to be about Dual 2.5 LCS troubleshooting and dialogue specific to readers looking for info about LCS repairs and troubleshooting.

Thanks

Hi,
I've been reading this thread with great interest. I am in the process of replacing o-rings and fluid in my G5. I stripped the mac when I bought it to remove the dust etc, I have also removed the LCS and have no visible leaks although I had the common 'white rice' crystals around the CPU coolers, I removed the crystals and added Artic Silver 5 to the CPU's. After I replaced the LCS the mac failed to start, I too saw the red LED on the motherboard. After removing the LCS I noticed that one processor board sat a little higher than the other, after I tightened the board the mac started both CPU's run idle at 55-57°. I'm not sure if you are still having an issue with the red LED but I hope this may help you or others.

 

[burnout8488]

Did you follow the recommended tightening sequence for the processors in the service manual?

 

[skorpan]

Did you follow the recommended tightening sequence for the processors in the service manual?

Yes, but I think I was being overly cautious.

I have been reading more about O-Ring replacement, and I think I will also add a gasket sealant when I replace the rings, probably Loctite 510.

I also came across this schematic of the G5 LCS. It may be of use to someone planning to work on it.

http://www.appleinsider.com/articles/04/06/17/diagrams_detail_apples_new_liquid_cooling_system.html

 

[mac.tastic]

I recently bought a G5 Quad for $350 that I found was was perfectly clean inside and zero signs of leaks. But, after a few minutes all the fans would revv to 2100-3200rpm.

Running any sort of load would cause CPU A Core 2 run upwards of 195*f while the rest were around 145*f. So I got real sick of the noise real quick and decided to take the risk of pulling the CPUs, and I was right! I disassembled the CPUs to find Core A had a spot not covered with thermal grease. (see attachments. Picture 1 is Core A, 2 is core B for comparison)

Now the temperatures peak around 186*f and settle down to 175*f. The fans still revv up with high load but they don't stay high like before. I used Arctic Silver 5 which claims to have a "break in" period, so hopefully it will cool down even more.

It has the "version 1" single pump LCS. Is there any possibility of upgrading to the dual pump system or does that take a different firmware to operate?

 

[mac.tastic]

Another update.

AppleFan.kext.
Stock code has it set to start to spool up up at 135*f and max them out at 144*f with very small even speed steps between and a very long delay before they spool down. I believe this is a major contribution to noise complaints.

<key>fan-hysteresis-temp</key>
				<integer>14080</integer>
				<key>fan-polling-period</key>
				<integer>8</integer>
				<key>fan-slowdown-delay</key>
				<integer>48</integer>
				<key>fan-speed-table</key>
				<array>
					<integer>14592</integer>
					<integer>14922</integer>
					<integer>15059</integer>
					<integer>15164</integer>
					<integer>15252</integer>
					<integer>15331</integer>
					<integer>15401</integer>
					<integer>15466</integer>
					<integer>15526</integer>
					<integer>15583</integer>
					<integer>15637</integer>
					<integer>15688</integer>
					<integer>15736</integer>
					<integer>15783</integer>
					<integer>15828</integer>
					<integer>15872</integer>
				</array>
				<key>fan-speedup-delay</key>
				<integer>8</integer>

I modified the code to spool up gradually 129*f-163* then ramp up to max quickly between 165*f-167*f. Slowdown delay was cut by 2/3 from 48 to 16.

<key>fan-hysteresis-temp</key>
				<integer>13300</integer>
				<key>fan-polling-period</key>
				<integer>8</integer>
				<key>fan-slowdown-delay</key>
				<integer>16</integer>
				<key>fan-speed-table</key>
				<array>
					<integer>13800</integer>
					<integer>14200</integer>
					<integer>14600</integer>
					<integer>15000</integer>
					<integer>15500</integer>
					<integer>16000</integer>
					<integer>15500</integer>
					<integer>16768</integer>
					<integer>17200</integer>
					<integer>17800</integer>
					<integer>18176</integer>
					<integer>18700</integer>
					<integer>18950</integer>
					<integer>19100</integer>
					<integer>19150</integer>
					<integer>19200</integer>
				</array>
				<key>fan-speedup-delay</key>
				<integer>8</integer>

These changes, along with setting performance to "automatic" have made the fans behave far more civilized. They now spool up quietly to maintain 135*f at average loads and 165*f at 100%x4 load.

 

[Trdinput]

DOA G5 overheat

I bought a DOA G5 from eBay. The Puter was overheating and the screen would freeze. I found this out by running an ordinary box fan through the unit and it prevented the dreaded freezing.

Here is what I did:

1. I completely tore the unit down to the cabinet; this took a special tool listed in xl8yourmac, a t handle hex key to remove LCS. I also bought the Craftsman tubing cutter.

2. I washed the logic board in warm soapy water, used an air compressor to blow it off, blow dried it on medium, put it in front of box fan for 48 hours to make sure it was DRY, DRY, DRY!

3. I rebuilt the Panasonic, not Delphi LCS, by cutting one of the rubber U shaped molded hoses to drain the system. The coolant was red and in great condition so I flushed it with a hose connected to my wife's Rubbermaid sports bottle filled with distilled water. Rinsed 3 times, used air compressor to completely purge each time, and refilled it with Fesser one red coolant from frozencpu.com. I refilled it with the same bottle and hose apparatus but noticed a lot of air in the system. I bought a small square container with a lid, customized a ViaAqua power head to accept two 1/4" ID hoses to connect them to the LCS. I Poured the Fesser One Red into the container with the powerhead, hooked up the hoses to the plastic resevoir and the copper coil and turned the apparatus on... good bye to all the trapped air. The outlet from the powerhead was hooked to the plastic resevoir on the lcs and the return to the square container came from the copper coil on the LCS. The amount of air pushed out was incredible! I used a silicone hose to replace the U shaped hose. It appears to be chemical resistant after soaking a piece of it in brake fluid and the Fesser. It is also extremely pliable and withstands high temps.

I used Arctic cooling MX-4 on the CPU. This is non conductive and guarantees it will work 8 years. To apply, I put a 1/8" glob in the middle of the CPU and used a Bamboo Skewer to move the paste around. I was able to remove any excess at this step.

4. I reassembled the entire LCS, put the logic board back in, plugged everything back in and here it is! No more kernel errors, (oh, I replaced the ram) , No more screen and mouse freezes, no more loud fans racing, what more can I ask for.

Before I did this, the U3 heat sink ran 189ºf at an idle, CPU A and B ran appx 176ºf. Now the fans barely come on, the U3 heat sink is currently 162ºf, CPU A is 137ºf and CPU B is 140ºf.

I forgot to mention, this is a G5 2.7 dual. If you would like a pic of how I removed the air, go to Laurietta1@hotmail.com and I will be glad to send it to your personal e mail.

I am 52 years old with a broken back. Honestly, if I can do this, anyone can. Lots of prayers help.

Happy Hunting,
Trdinput

I want to share my experiences with my G5 beginning with the symptoms that led me to discover that my LCS (liquid coolant system) had been leaking. Then share what I have done to the machine over the entire repair.

My machine specs:
Dual 2.5 Ghz running 10.5.8 used mostly for processing and manipulation of digital image files. It has 8 GB of RAM and 2 internal hard drives. The video card is what came with the machine. Other than adding the extra hard drive and the extra RAM there are no other hardware additions. I have a 17" and 23" Apple Displays running off the single video card. Externally I have 2 LaCie Pocket Drives (20 GB & 40 GB) and a 1.5 TB Western Digital MyBook hard drive all daisy chained via firewire.

This machine is usually running 24/7. On occasion when I had to restart, usually for a software update, I would get the chime, solid status light (the light above the power button), and the folder with a question mark. In the beginning I could do a hard shut down (hold down the power button) and try to boot again with success. I would then run Disk Utility and repair the permissions and go on about my business.

Over time the machine on start up would chime but the monitor would not come on and the fans would slowly speed up until they sounded like a jet fighter taking off. If I didn't do a hard shut down the machine would eventually shut off.

Sometimes I could restart from the OS install disk, run the disk utility, and the machine would start up fine. When that solution stop working I would dig around on the web for similar experiences and try other solutions. With the machine being 6-7 years old I thought that it might be the internal 3.6 volt battery and replaced it. Didn't seem to make a difference.

---I DID CALL APPLE AND SEE IF I COULD GET A FREE REPAIR OR A NEW MACHINE LIKE OTHER FOLKS I READ ABOUT WHEN THEIR LCS FAILED, EVEN IF THEIR MACHINE WAS OUT OF WARRANTY AND OUT OF APPLE CARE. IT SEEMS THAT AFTER 5 OR 6 YEARS FROM THE MANUFACTURER DATE APPLE WOULD TAKE CARE OF IT. MY MACHINE IS 7 YEARS OLD AND THEY NOW CONSIDER IT 'VINTAGE' AND PARTS ARE NO LONGER MADE FOR IT. I MIGHT TAKE IT TO MY LOCAL APPLE STORE IF MY ATTEMPT AT A REPAIR DOESN'T WORK AS A PLAN B------

Funny enough...if the computer was kept turned off over night it would boot the next day just fine. Now at this point it was obvious that it didn't like being turned off so I would wait to do any updates on Friday and the just power down the machine and hope it would start up on Monday.

I would also try to reset the PRAM, reset the PMU (pressing the coda switch on the mother board), and pull the power cord out of the machine for a couple of minutes before reconnecting and attempting to boot up.

In the final days leading up to the eventual inability to get the machine to boot I would be batch processing jpeg images in Lightroom and the machine would spontaneously go to sleep. At first I thought I had a Hot Spot active in a corner of the monitor that would activate the sleep mode. That was not the case.

After it would go to sleep I would wake it up by clicking the mouse or hitting a key. It would wake up, continue to process files, and after a minute or so it would go back to sleep.

I did have other apps running like Safari and PhotoShop (usually with a couple hundred megabytes of files open).

I had a Temperature Monitor app running that would show me the CPU temps and they would usually hover around 180 F and 200 F. The fans were usually running around (my estimate) 50%-75% power.

The final state of the computer before I started to check for a leak was upon start up I would get the chime, solid status light, no diagnostic LEDs internally, no video, and the machine would not respond to keyboard commands. So, I couldn't boot in another mode like safe, verbose, open firmware, or target. Also couldn't reset the PRAM or force open the CD drawer because the keyboard was unresponsive.

Thinking that it was a temp issue I throughly vacuumed out the inside of the case, radiator, and the outside of the case. I also cleaned all the fans. Still the machine wouldn't start.

I went exploring inside the machine looking for any gross fluid. I didn't see any but discovered that the absorbent pad under the LCS was saturated. I also tilted the machine and after a short time a small amount of liquid would appear. And there it was....my machine had sprung a leak.

If you are reading this then you might have read other posts on this site and others and learned about the horror stories on how the coolant killed their machine by either coming into contact with the logic board, processors, or power supply. I think I might have gotten away with no additional damage but don't know for sure until I get the LCS repaired and attempt to start up the machine.

As of this post I have removed the LCS and drained it by removing one of the hoses.
-----BE AWARE THAT THE SYSTEM MIGHT BE UNDER PRESSURE. THE COOLANT IS NOT VERY FRIENDLY TO SKIN, EYES, AND REALLY ANYTHING. HAVE EYE PROTECTION ON IF YOU ATTEMPT TO REMOVE A TUBE!--------

I have also removed the power supply and checked for any corrosion---there was a couple of trails of dried coolant on the outside of the power supply but no corrosion or visible damage. I put the power supply back.

I followed the post at http://www.xlr8yourmac.com/systems/G5_coolant_leaks.html to guide me on the LCS removal and disassemble. The plates that sit on the processors showed some corrosion around the edge and dried coolant. I cleaned the inside of the LCS behind the plates where there was a 'jelly' that I can only assume was old coolant.

It seems that the o-rings were the culprit in allowing the coolant to leach out of the LCS.

---THE INSTRUCTIONS LISTED AT http://www.xlr8yourmac.com/systems/G5_coolant_leaks.html ARE FOR A POWERMAC G5 DUAL 2.7. I FAILED TO ACTUALLY MEASURE THE O-RINGS THAT I TOOK OUT OF MY DUAL 2.5 AND JUST ORDERED THE RINGS LISTED IN THE POST. THEY ARE TOO LARGE FOR A 2.5 MACHINE--------

I purchased the o-rings at MSC Industrial Supply. 800-645-7270 and http://www.mscdirect.com. I was able to find the coolant listed in the xlr8yourmac.com post at http://www.performance-pcs.com for $19.95. The brand of the coolant, Cooler Master, doesn't carry that particular coolant any longer. The O-rings were around $13 for 50 rings (the smallest amount I could order).

After learning that the o-rings I ordered were to large I ordered the next smaller size. The specs on the smaller o-ring have a thickness of 1/16", Outside Dimension (O.D.) 1.375", and Inside Dimension (I.D.) 1.250. It is made of Viton, which according to a tech person at MCS is the best material for coming into the coolant (Glycol) and be under some pressure and heat (rated to 400 degrees F). The order number for this o-ring at MCS is 02049971. The AS568A Dash No. is 026. The Dash number is a standard across multiple industries based on OD, ID, and thickness.

I will conclude this post by saying that I have the coolant and I am waiting on the replacement o-rings which will be here in 2 days. If they fit then I will begin to reassemble and begin the process of recharging the LCS with coolant. I have read on other sites a bunch of methods to get the coolant into the radiator so there are no air bubbles. I will share my experience with that in a later post. I will also replace the rubber tubing on the LCS with something newer and hopefully clear to I will be able to visually see if the coolant, which is blue, is still in the LCS.

I am going to see if I can power up the pump on the LCS with an external power source and make sure it is running and might take it apart and clean it out or at the very least run water through it. IF I need a new pump I have read other posts where a pump located at http://www.newegg.com/Product/Product.aspx?Item=N82E16835108063 is $60. Better to learn that the pump on the LCS is broken now that the LCS is out of the computer.

I hope this post is helpful. I will answer any questions as promptly as I can.

 

[Nameci]

Congratulations man, now it is tempting to get the G5 quad.

 

[vohdoun]

It would be sweet if a custom PC watercooling kit could have been used on the G5's rather than these crummy sealed units.

 

[Pegasus777]

G5 Quad

I know it's virtually a year since the last posts on this LCS of G5s, but if there's anyone out there that knows of a site or posting that could help me with a G5 Quad. The LED lights indicate a temp. problem, the fans do the "powering up" noise and it does the freezing and shutdown.

This started 4 month ago, I took it a service place. Told it was the cooling system and that it was VINTAGE. Parts next to impossible to get. NO Apple support, so I was only charged for a light cleaning and a "Diagnostic" - $40.

It worked ... ok .... for 4 mon. now it does the Boot Up .... 15 sec. Shut Down!

I've read Many posts ... breaking "this" ... glue for "that" and the Leaking!!
I don't have anything leaking ... Nothing I can see or smell ... what I'm after at this point is a little direction for the "Tearing it Apart" phase of my foolish attempt to fix it myself.

The side is open, the dust cover out, the first 2 fans slid out and now I face the 7.5 x 9.5 plate with the Shiny G5 on it. I can't get it Off or Out.

I could use a little help with "anger management" so I haven't forced or punched anything on it yet ...
I'm just hoping for some guidance to get me to these pumps and tubes and whatevers without breaking anything ... please!

John (Niagara Falls, Canada)

 

[666sheep]

Google "Power Mac Late 2005 service manual"