Can't hold Vacuum in cooling system - 986 Forum - The Community for Porsche Boxster & Cayman Owners

redeye280z · 03-19-2015, 03:45 PM

I just got the airlift cooling system filler. tonight I tried using it but I couldn't get it to go higher than 10 inch and as soon as I closed the valve I would lose all vacuum. The loss of vacuum seem to be coming from the top of the tank but I am not sure if it's the seal on the tool or maybe the relief valve on the tank. I checked the hoses and they all seem to be nice and tight. Need some help on what to look for. By the way which adapter on the airlift are you guys using one seems a tad too small and the other a little too big. Maybe I am missing something.

NewArt · 03-19-2015, 04:51 PM

Yes, I seem to have the same problem. I can pull 25-27 on the airlift but then it drops. If you're only getting 10, do you have enough volume/pressure in your compressor? It needs to be set at 100 lbs to get it up there.
I too have the impression that it's a problem with the tank. I received my leak-down tester yesterday and will be checking the engine health tomorrow.

redeye280z · 03-20-2015, 01:07 AM

I can barely get up to 10.The compressor is at 100 lbs and my tank is new. I am at a loss here. Maybe I am not getting a very good seal at the the top of the tank but I am losing the vacuum instantly and very rapidly.

NewArt · 03-20-2015, 06:11 AM

You've just replaced the expansion tank? Check for leaks or a loose connection where you were working.
Oh, I see that you have checked the hoses at the back of the tank.
Some have used the conical adapter but I have used the regular sleeve adapter with success.

steved0x · 03-20-2015, 06:38 AM

Quote:

Originally Posted by redeye280z

By the way which adapter on the airlift are you guys using one seems a tad too small and the other a little too big. Maybe I am missing something.

I used the conical adapter, the other ones all seemed to be just a touch too big or too small.

redeye280z · 03-20-2015, 06:52 AM

I will try checking all the hoses again but I can here the vacuum loss from the top side of the tank. I just hope the tank is not defective. I do have some coolant already in the system but I don't think that would be a problem.

NewArt · 03-20-2015, 07:31 AM

Coolant in the system shouldn't cause any problem.

redeye280z · 03-20-2015, 06:11 PM

Did a few more tests tonight and found that the bleeder valve is losing vacuum. This is a new tank not sure what to do next? I don't want to remove the tank to return it. Is it possible to change just the valve cause I think that would fix the problem.

NewArt · 03-20-2015, 06:27 PM

I have my suspicions on mine as well but it's difficult to discern the actual culprit. I'm doing a leak down test tomorrow to see if there's some other problem but I get the feeling there's something not right up top.
The o-rings on the bleeder valve can be changed but that shouldn't be necessary on a new or recent tank. How to test it? No idea.

JFP in PA · 03-21-2015, 06:58 AM

Quote:

Originally Posted by NewArt

I have my suspicions on mine as well but it's difficult to discern the actual culprit. I'm doing a leak down test tomorrow to see if there's some other problem but I get the feeling there's something not right up top.
The o-rings on the bleeder valve can be changed but that shouldn't be necessary on a new or recent tank. How to test it? No idea.

If you think the tank or bleeder are leaking, use a system pressure tester to pressurize the system and then coat the bleeder area with a soapy water mix; if it is leaking, you will get a ton of bubbles.

redeye280z · 03-21-2015, 09:38 AM

I finally did a few more tests today and found that the bleeder valve was leaking. I took it apart and compared it to the one from my tank that was cracked and was surprised to find that the prints were too thin to make a good seal. I had to run to the local auto parts to find some new o rings. I finally put it all back did the test and it held the vacuum so I refilled the system. Now my temperature light won't stop flashing. The tank is a little over filled right now is it possible that the light would flash if you overfill? What could the cause be the sensor was fine in the old tank.

JFP in PA · 03-21-2015, 09:54 AM

Quote:

Originally Posted by redeye280z

I finally did a few more tests today and found that the bleeder valve was leaking. I took it apart and compared it to the one from my tank that was cracked and was surprised to find that the prints were too thin to make a good seal. I had to run to the local auto parts to find some new o rings. I finally put it all back did the test and it held the vacuum so I refilled the system. Now my temperature light won't stop flashing. The tank is a little over filled right now is it possible that the light would flash if you overfill? What could the cause be the sensor was fine in the old tank.

Four functions of the coolant warning light:

1. Engine coolant level too low
— light flashes slowly (0.5 Hz)
2. Engine compartment temperature too high
— light flashes slowly (0.5 Hz) (engine compartment blower might be faulty)
3. Engine coolant temperature too high
— light is lit; pointer on the right
4. Temperature sensor at water outlet faulty
— light flashes rapidly (1 Hz); pointer on the right

Note
The temperature warning in point three is indicated if the conditions "engine coolant temperature too high" and "engine coolant level too low" are present simultaneously
(1Hz = 1 flash per second. 0.5Hz = 2 seconds per flash)

redeye280z · 03-21-2015, 10:22 AM

The light started flashing immediately after I started the car. The level of coolant was top up to the max line and the engine was still cold. The sensor was fine when I took it from the old tank. Is there any way to test the sensor to see if it is working properly. Also as a note when I disconnect the harness from the plug it still flashes I was under the impressing that unplugging it would stop the light from blinking. Logically it has to be something with the sensor since I have just finished removing all these parts and putting them back.

JFP in PA · 03-21-2015, 11:22 AM

Quote:

Originally Posted by redeye280z

The light started flashing immediately after I started the car. The level of coolant was top up to the max line and the engine was still cold. The sensor was fine when I took it from the old tank. Is there any way to test the sensor to see if it is working properly. Also as a note when I disconnect the harness from the plug it still flashes I was under the impressing that unplugging it would stop the light from blinking. Logically it has to be something with the sensor since I have just finished removing all these parts and putting them back.

Have you tried timing the flash and comparing that to the data above?

redeye280z · 03-21-2015, 01:55 PM

It's a slow flash. I am almost quite certain that maybe the coolant level sensor went bad in the transfer. I was just wondering is there a way of testing it?

JFP in PA · 03-21-2015, 02:38 PM

Quote:

Originally Posted by redeye280z

It's a slow flash. I am almost quite certain that maybe the coolant level sensor went bad in the transfer. I was just wondering is there a way of testing it?

I would also check the engine compartment fan for function as that will also cause the slow flash sequence, and it is just ahead of where you have been working. Do you have the Durametric software?

NewArt · 03-21-2015, 02:44 PM

I get lots of bubbles at 10 lb pressure! Relatively new "genuine Porsche" tank, guess I'll replace the "genuine Porsche " o-rings!
Redeye, all those plastic fiddly bits break and die if you look at the crossways.

redeye280z · 03-21-2015, 05:01 PM

I dont have the duremetric software unfortunately. I do some more diagnostics tomorrow. I just find it would be a coincidence that all of a sudden I have a new issue.

New art I took my time when taking apart the bleeder valve I don't really like the fact that it screws into plastic. I was amazed that a new tank had this defect I guess that's whAt you get when most of this stuff is made in China.

JFP in PA · 03-21-2015, 05:36 PM

Quote:

Originally Posted by redeye280z

I dont have the duremetric software unfortunately. I do some more diagnostics tomorrow. I just find it would be a coincidence that all of a sudden I have a new issue.

New art I took my time when taking apart the bleeder valve I don't really like the fact that it screws into plastic. I was amazed that a new tank had this defect I guess that's whAt you get when most of this stuff is made in China.

With the Durametric you would be able to see more information and do things like test the engine compartment fan or see the fault causing the flashing light.

Usually the bigger problem is the screws rather than the plastic, the screws love to simply snap off.

redeye280z · 03-22-2015, 06:48 AM

Quote:

Originally Posted by JFP in PA

With the Durametric you would be able to see more information and do things like test the engine compartment fan or see the fault causing the flashing light.

Usually the bigger problem is the screws rather than the plastic, the screws love to simply snap off.

I found someone who has a Durametric version 5 and wants 75 bucks for it. Is this worth my time or should I look for the newer version?